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XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis. ¿Hacia un Modelo Integrador? Diego Mezzano Depto. HematologíaOncología P. Universidad Católica de Chile

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Page 1: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

XVI Congreso Chileno de HematologiacuteaVI Congreso de Medicina TransfusionalCoquimbo Septiembre 2008

Hemostasia y Trombosis iquestHacia un Modelo Integrador

Diego MezzanoDepto Hematologiacutea‐OncologiacuteaP Universidad Catoacutelica de Chile

MacFarlane RG Nature 1964MacFarlane RG Nature 1964ldquoldquoEnzyme CascadeEnzyme Cascaderdquordquo

Davie EW and Ratnoff OD Science 1964Davie EW and Ratnoff OD Science 1964ldquoldquoWaterfall SequenceWaterfall Sequencerdquordquo

Broze JG GJ

Osterud B and Rapaport SI PNAS 1977

Broze GJ Jr

Broze GJ Jr et alBiochemistry 1990

Broze GJ Jr

Broze GJ Jr

Gailani D Broze GJ Science 1991Naito K Fujikawa K JBC 1991

Broze GJ Jr

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 2: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

MacFarlane RG Nature 1964MacFarlane RG Nature 1964ldquoldquoEnzyme CascadeEnzyme Cascaderdquordquo

Davie EW and Ratnoff OD Science 1964Davie EW and Ratnoff OD Science 1964ldquoldquoWaterfall SequenceWaterfall Sequencerdquordquo

Broze JG GJ

Osterud B and Rapaport SI PNAS 1977

Broze GJ Jr

Broze GJ Jr et alBiochemistry 1990

Broze GJ Jr

Broze GJ Jr

Gailani D Broze GJ Science 1991Naito K Fujikawa K JBC 1991

Broze GJ Jr

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 3: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Osterud B and Rapaport SI PNAS 1977

Broze GJ Jr

Broze GJ Jr et alBiochemistry 1990

Broze GJ Jr

Broze GJ Jr

Gailani D Broze GJ Science 1991Naito K Fujikawa K JBC 1991

Broze GJ Jr

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 4: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Broze GJ Jr et alBiochemistry 1990

Broze GJ Jr

Broze GJ Jr

Gailani D Broze GJ Science 1991Naito K Fujikawa K JBC 1991

Broze GJ Jr

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 5: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Broze GJ Jr

Gailani D Broze GJ Science 1991Naito K Fujikawa K JBC 1991

Broze GJ Jr

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 6: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Gailani D Broze GJ Science 1991Naito K Fujikawa K JBC 1991

Broze GJ Jr

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 7: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Baglia FA Walsh PN Biochem 1998

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 8: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Insuficiencias del ModeloExperimentos in vitro usan fosfoliacutepidos que no replican resultados obtenidos con membranas celulares ricas en factores adicionales

Las plaquetas tienen una membrana rica en receptores y factores de la coagulacioacuten superficie oacuteptima para el ensamble de los complejos multimoleculares de la coagulacioacuten

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 9: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Copyright copy2002 American Society of Hematology Copyright restrictions may apply

Brummel K E et al Blood 2002100148-152

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 10: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Platelets are activated prior to the burst of thrombin generation

Roberts HR et al

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 11: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Platelets are required for thrombin generation in the model system

Monroe DM et al ATVB 2002

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 12: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Cell‐based Model of Thrombin GenerationCell‐based Model of Hemostasis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 13: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Initiation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 14: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Amplification

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 15: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Propagation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 16: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Coagulation

A cell‐based model of thrombin generation Roberts HR et al Sem Thromb Haemost 2006

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 17: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

ABSTRACT Arterial thrombosis is considered to arisefrom the interaction of tissue factor (TF) in the vascular wallwith platelets and coagulation factors in circulating bloodAccording to this paradigm coagulation is initiated after avessel is damaged and blood is exposed to vessel‐wall TF Wehave examined thrombus formation on pig arterial media(which contains no stainable TF) and on collagen‐coated glassslides (which are devoid of TF) exposed to flowing nativehuman blood In both systems the thrombi that formed duringa 5‐min perfusion stained intensely for TF much of which wasnot associated with cells Antibodies against TF caused 70reduction in the amount of thrombus formed on the pigarterial media and also reduced thrombi on the collagencoatedglass slides TF deposited on the slides was active asthere was abundant fibrin in the thrombi Factor VIIai apotent inhibitor of TF essentially abolished fibrin productionand markedly reduced the mass of the thrombi Immunoelectronmicroscopy revealed TF‐positive membrane vesicles thatwe frequently observed in large clusters near the surface ofplatelets TF measured by factor Xa formation was extractedfrom whole blood and plasma of healthy subjects By usingimmunostaining TF‐containing neutrophils and monocyteswere identified in peripheral blood our data raise the possibilitythat leukocytes are the main source of blood TF Wesuggest that blood‐borne TF is inherently thrombogenic andmay be involved in thrombus propagation at the site ofvascular injury

Giesen PLA et al PNAS 1999

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 18: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Blood‐borne TF iquestde doacutende viene

Monocitos radic

Granulocitos

Endotelio

Micropartiacuteculas radic

Plaquetas radic‐

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 19: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Table 3 Plasma markers of oxidative stress endothelial activationdysfunction and haemostatic activation in patients with chronic renal failure and healthy controls (Kidney Int 2001 601844-50)

Plasma concentration of Patients (n = 64)

Controls(n = 16 ndash 40)

p=

TBARS (micromolL) 198 plusmn 048 155 plusmn 039 0009AOPP (mmol eq chloramine T) 281 (45-915) 121 (14-414) 00001von Willebrand factor () 182 plusmn 78 116 plusmn 46 00001Soluble thrombomodulin (ngmL) 157 plusmn 21 57 plusmn 045 00001Soluble ICAM-1 (ngmL) 301 (174-508) 233 (179-275) 00001TAT (microgL) 33 (094-142) 21 (084-47) 003PF1+2 (nmolL) 30 plusmn 11 18 plusmn 08 00001PAP (microgL) 874 (146-2302) 475 (321-805) 00001FnDP (ngFEmL) 675 (118-3622) 173 (9-543) 00001FgDP (ngFEmL) 391 (20-5875) 89 (20-236) 00001

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 20: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

0 0

0 2

0 4

0 6

0 8

1 0

1 2

1 2 3 4

TFA

CTI

N N

OR

MA

LIZE

D R

ATI

O(a

rbitr

ary

units

)

H E A L T H YIN D IV ID U A L S

T O T A LC R F

C R FP R E -D IA L YS IS

C R FD IA L YS IS

p lt 0 0 0 2 5

p lt 0 0 0 0 1

p lt 0 0 0 5

BASAL MONOCYTE TF EXPRESSION IS INCREASED IN CRF PATIENTSCOMPARED WITH HEALTHY INDIVIDUALSA

B

ACT (462 bp)

TF (282 bp)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 21: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Platelet‐associated tissue factor contributes to the collagen‐triggered activation of blood coagulation Zillmann A Luther T Muumlller I Kotzsch M Spannagl M Kauke T Oelschlaumlgel U Zahler S Engelmann BBiochem Biophys Res Commun 2001 Feb 23281(2)603‐9

Platelet activation induces cell‐surface immunoreactive tissue factor expression which is modulated differently by antiplatelet drugs Camera M Frigerio M Toschi V Brambilla M Rossi F Cottell DC Maderna P Parolari A Bonzi R De Vincenti O Tremoli EArterioscler Thromb Vasc Biol 2003 Sep 123(9)1690‐6

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 22: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Escaping the Nuclear Confines Signal-Dependent Pre-mRNA Splicing in Anucleate Platelets Cell Volume 122 Issue 3 Pages 379 - 391M Denis N Tolley M Bunting H Schwertz H Jiang S Lindemann C Yost F Rubner K Albertine K Swoboda

Este artiacuteculo dio sustento cientiacutefico a otros previos que reportaban siacutentesis de IL1β bcl‐2 y PAI‐1 por las plaquetas

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 23: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

11 Evidence of TF synthesis by human plateletsEvidence of TF synthesis by human platelets

2 Is TF present in non‐stimulated circulating platelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 24: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Classical RTClassical RT‐‐PCR reveals that human PCR reveals that human platelets platelets express TFexpress TF‐‐mRNA mRNA

200 bp

600 bp

1500 bp

LPS‐stimulated PBMC (2 h) increase dramatically TF‐mRNA expression but also contain GPIbα‐mRNA denoting contamination with platelets

β-actin

GPIbαβ-a

ctin

GPIbα

200 bp

600 bp

2000 bp

Stimulated (5mM TRAP 15 min) human platelets free of monocytes express TF-mRNA after activation and frequentlyhelliphellip even without stimulation

CD14CD14

TF

TF

Resting Stimulated

(J Exp Med 2006 2032433 Blood 2007 1095242)

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 25: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

350bp

50 bp

Plat β

‐actin

PBMC β

‐actin

PBMC T

F

Plat T

F

RTRT‐‐PCR TRAPPCR TRAP‐‐activated platelets (15 min) but not activated platelets (15 min) but not PBMC of one individual express TFPBMC of one individual express TF‐‐mRNAmRNA

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 26: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

604 kDa

472 kDa

351 kDa

TRAP ndash + ndash + Puromycin ndash ndash + +

Metabolic radioMetabolic radio‐‐labeling with labeling with 3535SS‐‐methionine methionine demonstrates TF neodemonstrates TF neo‐‐synthesis by platelets synthesis by platelets

TF synthesis (asymp47 kDa) by non stimulated platelets is enhanced with activation

(band of asymp60kDa) and inhibited by puromycin

IP polyclonal α‐TF

(Blood 2007 1095242)

TRAP ndash ndash + +Puromycin ndash + ndash +

620 kDa

475 kDa

325 kDa

IP MoAb α‐TF (Am Diag 4509)

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 27: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

1 Conclusions1 Conclusions

Isolated human platelets express TF-mRNA and neo-synthesize the protein These phenomena were observed in non-stimulated conditions but mainly after activation

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 28: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

1 Evidence of TF synthesis by human platelets

22 Is TF present in nonIs TF present in non‐‐stimulated circulating stimulated circulating

plateletsplatelets

3 TF‐dependent pro‐coagulant activity of human platelets

Possible mechanisms of TF activation

4 Is this TF hemostatically relevant

OUTLINEOUTLINE

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 29: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

60 kDa

47 kDa

30 KDa

hrTFN‐S 15 60min min

Western Blot of membrane fractions of nonWestern Blot of membrane fractions of non‐‐stimulated (Nstimulated (N‐‐S) and TRAPS) and TRAP‐‐activated plateletsactivated platelets

(Blood 2007 1095242)

Consistently TF protein was present in nonConsistently TF protein was present in non‐‐stimulated plateletsstimulated platelets

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 30: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Pearson Coeff 01855

TF GPIbα

Non‐stimulated non‐permeabilized human platelets express TF protein which appears centralized in relation to GPIbα

Pearson Coeff 03188

TRAP‐stimulation strikingly enhances the immuno‐reactivity of TF and its co‐localization with GPIbα

GPIbαTF

TF GPIbα

Merge

Merge

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 31: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

This apparent externalization of TF is also observed This apparent externalization of TF is also observed after membrane biotinilation and TF after membrane biotinilation and TF immunoprecipitationimmunoprecipitation

IP polyclonal‐αTF

83 kDa

642 kDa

WB Streptavidin‐HRP 47 kDa

37 kDaTF is transferred to plasma membrane after TRAP stimulation

WB MoAb α‐TF 4509 47 kDa

N‐S 30 60 90min min min

Again TF is present in non‐stimulated platelets

(Blood 2007 1095242)(J Thromb Haemost 20075(Suppl 2) O‐W‐074)

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 32: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

GPIbαTF VisIn contrast resting nonIn contrast resting non‐‐permeabilized PBMC do not exhibit permeabilized PBMC do not exhibit membrane TF Platelets always present in these membrane TF Platelets always present in these preparations contain TF copreparations contain TF co‐‐localized with GPIblocalized with GPIbαα

Merge

GPIbα

TF

TF

GPIbα

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 33: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

TFGPIbα

Merge

GPIbα TF

Merge

GPIbα TF

Merge

GPIbα TF

Merge

6 microM

However TF protein appears in LPS‐stimulated PBMC (2 h) Again high expression of TF‐GPIbα is observed in ldquocontaminatingrdquo platelets

Blood 2007 1095242

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 34: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

TFTF‐‐related prorelated pro‐‐coagulant activity (PCA) is not coagulant activity (PCA) is not inhibited by puromycin during a 2inhibited by puromycin during a 2‐‐h period denoting h period denoting that PCA depends on already stored TF in plateletsthat PCA depends on already stored TF in platelets

0 25 50 75 100 1250

10

20

30

Time (minutes)

Pro

coag

ulan

t act

ivity

(AU

2x

107 p

late

lets

)

Puromycin

Control

(Blood 2007 1095242)

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 35: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

2 Conclusions2 Conclusionsa TF is demonstrated in N-S platelets by western blotting

membrane biotinilation with immunoprecipitation and immunofluorescence-confocal microscopy

b In contrast surface exposure of TF in PBMC is detected only after 2-hour stimulation with LPS

c TF activity is not inhibited by simultaneous incubation with puromycin suggesting that TF is already stored in platelets

d These findings support the idea that human platelets contain stored TF likely synthesized by circulating platelets or alternatively derived from megakaryocytes

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 36: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Thrombus Formation In Vivo

Furie B and Furie B N Engl J Med 2008359938-949

Furie B and Furie B N Engl J Med 2008359938-949

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 37: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

Is this coIs this co‐‐localization of TF and GPIblocalization of TF and GPIbαα in activated platelets in activated platelets functionally relevantfunctionally relevant

Pearson Coeff 057

5 microm

GPIbα

MergeTF

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 38: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

PLATELET‐BASED MODEL OF HEMOSTASIS A PROPOSAL

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions
Page 39: XVI Congreso Chileno de Hematología VI Congreso de ... · XVI Congreso Chileno de Hematología VI Congreso de Medicina Transfusional Coquimbo, Septiembre 2008. Hemostasia y Trombosis

ACKNOWLEGMENTSACKNOWLEGMENTSOlga Panes conceived the study as main author performed the radiolabeling assays WBacutes IPacutes biotinilation and pro‐coagulant assays

Valeria Matus PhD developed all the molecular biology studies

Claudia Saacuteez PhD performed all the imaging studies

Paula Ibarra BQ thesist did the lipid raft studies

Jaime Pereira MD contributed in the design of the study discussion and critical interpretation of data and provided original ideas along the study

Antibodies against TF and GPIbα were kindly provided by Jim Morrissey Bob Montgomery and W Ruff

  • Insuficiencias del Modelo
  • Initiation
  • Amplification
  • Propagation
  • Coagulation
  • Blood-borne TF iquestde doacutende viene
  • Platelet activation induces cell-surface immunoreactive tissue factor expression which is modulated differently by antiplatel
  • 1 Conclusions
  • 2 Conclusions