Prolonged Diabetes Reversal after intraportal xenotransplantation of wild-type porcine islets in

immunosuppressed nonhuman primates Hering et al, Nature Medicine 12:301-303, 2006

• Reversal Diabetes > 100 days Porcine islet transplants into streptozotocin diabetic cynomolgus macaques

• Required Rx with toxic regimen including anti-CD154, leflunomide, basiliximab, FTY720 and everolimus

• No Gal-specific antibody mediated hyperacute rejection

Five-Year Follow-Up After Clinical Islet Transplantation

Ryan et al, Diabetes 54:2060-2069, 2005.

0

20

40

60

80

100

0 12 24 36 48 60

% Cpep Positive % Insulin Independent

Months of Follow-up

Percent derived from life Table

Issues in Islet Graft Issues in Islet Graft TransplantationTransplantation

•Allograft immunity

•Xenograft immunity

•Autoimmunity

TransplantImmunity Autoimmunity

Islets

00

100000

100000

200000

200000

300000

300000

400000

400000

500000

500000

600000

600000

Number of transplantsNumber of transplants

IsletIslet

PancreasPancreas

HeartHeart

KidneyKidney

World Experience in Organ / Tissue World Experience in Organ / Tissue TransplantationTransplantation

>500,000>500,000

>50,000>50,000

>13>13,000,000

<500<500

Autografts:Autografts: islets obtained islets obtained from the recipientfrom the recipient to toprevent pancreatectomy-induced diabetes prevent pancreatectomy-induced diabetes Autografts:Autografts: islets obtained islets obtained from the recipientfrom the recipient to toprevent pancreatectomy-induced diabetes prevent pancreatectomy-induced diabetes

Allografts: Allografts: islets obtained from an islets obtained from an unrelatedunrelateddonordonor to prevent pancreatectomy-induced diabetes to prevent pancreatectomy-induced diabetes

Allografts + IDDM: Allografts + IDDM: islets obtained from an islets obtained from an unrelated donor after or at the same time as unrelated donor after or at the same time as kidney transplantationkidney transplantation

Clinical Experience in Islet TransplantationClinical Experience in Islet Transplantation

Islet Transplantation Registry Islet Transplantation Registry

10090

80

70

60

5040

30

0

2010

0 1 2 3 4 5 76 8 9 1210 11

Autografts (n=50, 50%)Autografts (n=50, 50%)

Allografts (n=15, 40%)Allografts (n=15, 40%)

Allografts + IDDM (n=200, 8%)Allografts + IDDM (n=200, 8%)

Months post-Months post-transplantationtransplantation

1990 - 19971990 - 1997%

In

suli

n-I

nd

epen

den

ce%

In

suli

n-I

nd

epen

den

ce

IsletsIslets

Possible Reasons for Islet Graft Possible Reasons for Islet Graft FailureFailure

Allograft rejectionAllograft rejectionDisease recurrenceDisease recurrence

Insufficient islet massInsufficient islet mass Poor quality of isletsPoor quality of islets

Toxicity of anti-Toxicity of anti-rejection drugsrejection drugs

Failure to engraftFailure to engraft

Insulin resistanceInsulin resistance

`Edmonton’ Protocol`Edmonton’ Protocol`Edmonton’ Protocol`Edmonton’ Protocol

• Islet-alone transplantation trialIslet-alone transplantation trial

• Standard immunosuppressive therapy was Standard immunosuppressive therapy was replaced with a steroid-free protocol: replaced with a steroid-free protocol:

• Type 1 diabetic patients received two Type 1 diabetic patients received two transplantstransplants of large numbers of high quality islets.of large numbers of high quality islets.

University of Alberta, Edmonton, AlbertaUniversity of Alberta, Edmonton, AlbertaUniversity of Alberta, Edmonton, AlbertaUniversity of Alberta, Edmonton, AlbertaJ. Shapiro, M.D.J. Shapiro, M.D. R. Rajotte, Ph.D.R. Rajotte, Ph.D.

DaclizumabDaclizumab (DZB) (anti-IL2 receptor antibody) (DZB) (anti-IL2 receptor antibody)Daily doses of Daily doses of sirolimussirolimus and low-dose and low-dose tacrolimustacrolimus

Eligibility CriteriaEligibility CriteriaEligibility CriteriaEligibility Criteria

• Evidence of early diabetic nephropathy or other Evidence of early diabetic nephropathy or other secondary complicationssecondary complications

• Hypoglycemia unawareness requiring medical Hypoglycemia unawareness requiring medical assistanceassistance

• Uncontrolled blood sugars despite intensive Uncontrolled blood sugars despite intensive insulin therapy (“ brittle diabetes”).insulin therapy (“ brittle diabetes”).

• 18-55 years of age, have had IDDM for >5 18-55 years of age, have had IDDM for >5 yearsyears

Exclusion CriteriaExclusion CriteriaExclusion CriteriaExclusion Criteria

• cardiac disease or psychiatric illnesscardiac disease or psychiatric illness

• active alcohol or substance active alcohol or substance abuseabuse• previous transplantprevious transplant

• a history of malignancy or abnormal liver a history of malignancy or abnormal liver functionfunction• an active infection (HIV, Hepatitis B or C, an active infection (HIV, Hepatitis B or C, TB)TB)

• 13 consecutive cases of insulin-13 consecutive cases of insulin-independence with a duration of (longest > independence with a duration of (longest > 2.5 years) 2.5 years)

• no episodes of acute rejection and no episodes of acute rejection and minimal toxicity from anti-rejection drug minimal toxicity from anti-rejection drug therapytherapy

`Edmonton Protocol’`Edmonton Protocol’`Edmonton Protocol’`Edmonton Protocol’ResultsResults

• no episodes of hypoglycemiano episodes of hypoglycemia

• normalization of HbA1C values (mean normalization of HbA1C values (mean of 5.7% at 3 and 6 months post-of 5.7% at 3 and 6 months post-transplantation)transplantation)

600

500

400

300

200

100

0

2 4 6 8 10 12 2 4 6 8 10

600

500

400

300

200

100

012

a.m. p.m.

Post-transplantPost-transplant

Pre-transplantPre-transplant

Time of dayTime of day

Blo

od

glu

cose (

mg

/dl)

Blo

od

glu

cose (

mg

/dl) B

lood

glu

cose (

mg

/dl)

Blo

od

glu

cose (

mg

/dl)

Shapiro et al. Shapiro et al. N Engl J Med N Engl J Med 2000; 343:230-2000; 343:230-238238

Islet Transplantation: The NIH ExperienceDiabetes Care 2003: 26:3288-95

• Major Procedure ComplicationsPartial portal vein thrombosisIntra-abdominal hemorrhage

• Immunosupression ComplicationsKidney ToxicitySirolimun-induced Pneumonitis

• Three Patients Discontinued Immunotherapy

½ Patients insulin-independent at one year

Decreased Hypoglycemia and less severe Hypoglycemia

0

10

20

30

40

50

60

70

80

90

100

Panc Alone Panc after Kidney Combined Panc Kidney

Transplanted Waiting List

Percent 4 Year Survival with Pancreas Transplant

Ventrom et al JAMA 2003; 290: 2817-2823

Future DirectionsFuture DirectionsFuture DirectionsFuture Directions

• Reduce requirement to single pancreas / Reduce requirement to single pancreas / recipientrecipient

• Interventions to reduce peri-transplant Interventions to reduce peri-transplant inflammationinflammation

• Progress towards ‘tolerizing’ Progress towards ‘tolerizing’ strategiesstrategies

Alternative sources of tissueAlternative sources of tissueAlternative sources of tissueAlternative sources of tissue

• insulin-producing cell insulin-producing cell lineslines

• xenografts (other xenografts (other species)species)

• stem cellsstem cells

Experimental Islet Experimental Islet TransplantationTransplantation

C57Bl/6 mouse (H-2b)Remove pancreas

Isolate islets

Transplant islets under kidney capsule

Streptozotocin-induced diabetic BALB/c mouse (H-2d)

Key Components to Islet Key Components to Islet Allograft Cellular RejectionAllograft Cellular RejectionKey Components to Islet Key Components to Islet

Allograft Cellular RejectionAllograft Cellular Rejection

• DonorDonor-derived APCs -derived APCs

• Host CD8 T cells Host CD8 T cells

• DonorDonor MHC class I MHC class I expressionexpression

• Variable requirement for Variable requirement for CD4 T CD4 T cell help cell help

Key Components to Islet Key Components to Islet Xenograft Cellular RejectionXenograft Cellular Rejection

Key Components to Islet Key Components to Islet Xenograft Cellular RejectionXenograft Cellular Rejection

• HostHost-derived APCs -derived APCs

• Host CD4 T cells Host CD4 T cells

• HostHost MHC class II MHC class II expressionexpression

Conclusion / Hypothesis Conclusion / Hypothesis Conclusion / Hypothesis Conclusion / Hypothesis

• Xenograft Rejection and Xenograft Rejection and Autoimmune Autoimmune pathogenesispathogenesis --> --> Predominant CD4-Predominant CD4- dependent dependent ‘indirect’ recognition‘indirect’ recognition

• Allograft RejectionAllograft Rejection --> Predominant --> Predominant CD8-CD8- dependent ‘direct’ dependent ‘direct’ recognitionrecognition

Anti-LFA-1 Therapy Facilitates Long-Anti-LFA-1 Therapy Facilitates Long-Term Islet Allograft AcceptanceTerm Islet Allograft Acceptance

((C57Bl/6 --> BALB/cC57Bl/6 --> BALB/c))

0

20

40

60

80

100

0 20 40 60 80 100

% G

raft

s F

un

ctio

nin

g

Days Post Transplantation

Anti-LFA-1 (n = 20)Control Ig (n = 10)

Failure of Anti-LFA-1 to Prevent Disease Failure of Anti-LFA-1 to Prevent Disease RecurrenceRecurrence

((NOD --> NODNOD --> NOD))

0

20

40

60

80

100

0 20 40 60 80 100

% G

raft

s F

unct

ioni

ng

Days Post Transplantation

Untreated (n = 10)

Anti-LFA-1 (n = 8)

Young SZ-NOD (n = 3)

11000088006600440022000000

2200

4400

6600

8800

110000

Anti-CD4 but not anti-CD8 therapy preventsAnti-CD4 but not anti-CD8 therapy preventsAnti-CD4 but not anti-CD8 therapy preventsAnti-CD4 but not anti-CD8 therapy prevents

acute disease recurrence in NOD miceacute disease recurrence in NOD mice acute disease recurrence in NOD miceacute disease recurrence in NOD mice

Days Post-transplantationDays Post-transplantation Days Post-transplantationDays Post-transplantation

Untreated (n=8)Untreated (n=8)

Anti-CD8 (116-13.1; n=10)Anti-CD8 (116-13.1; n=10)

Anti-CD4 (GK1.5; n=9)Anti-CD4 (GK1.5; n=9)

% G

raft

s F

un

ctio

nin

g%

Gra

fts

Fu

nct

ion

ing

% G

raft

s F

un

ctio

nin

g%

Gra

fts

Fu

nct

ion

ing

C

C

CAPC T(C) T (C)

T(C)

CoSCoS

(1)(1)

(1)(1)

(2)(2)

NoNoResponseResponse

C

C

C cell

The Stimulator Cell ModelThe Stimulator Cell Model

DIRECTDIRECT

T(B.X) T(B.X)

INDIRECTINDIRECT

(1)(1)

(2)(2)T(A) T (A)

(1)(1)

(2)(2)

A

A

AAPC

DONOR

Shed GraftShed Graft AntigensAntigens

(X)(X)

B

B

APCHOST

Bx

x

x

GRAFT

Delayed-Type Hypersensitivity

CD4 T Cell

B Cell Help

CD8 T CellHelp

No direct

CD4II (x )

'INDIRECT'

Shed graftantigen (X)

II

II

APCHOST

IIx

x

x

CD8IAPC-depleted

islet allograftresponse

DIRECT

CD4 II (X)

INDIRECT

CD8I

IIAPCHOST

x

x

x

II

II

( )

APCDONOR I

I

I

Shed graftantigen (X)

APC-depletedislet allograft

TOLERANCETOLERANCE