PL Meroni

Dip. di Reumatologia, ASST CTO-Ist. G Pini; Dept. Clinical Sciences & Community Health, Univ. of Milan (I)

Update on APS

consultant to Inova Diagnostics Inc., Pfizer, Abbvie, UCB, MSD.

Disclosures: Dr. PL Meroni

Outline of presentation • Obstetric vs vascular APS • Update on the pathogenesis • The rational for the treatment • The real life in OBG APS treatment • Risk assessment • Refractory cases

Classification criteria for APS – Vascular thrombosis: > 1 episode – Pregnancy morbidity: - Abortions (<10 sem.): > 3 - Fetal death (>10 sem.): > 1 - Prematures (<34 sem.): > 1

– – aCL (IgG/IgM): > 2 determ. (med/high titre) – Anti-b2GPI (IgG/IgM) : > 2 determ. (med/high titre) – LAC: > 2 determ.

Clinical criteria

Laboratory criteria

Classification: 1 clinical criteria + 1 laboratory criteria

Myiakis et al JTH ‘06

Miascarriage, stillbirth, pre-eclampsia, IUGR,

• Obstetric APS is a specific subset within the APS box. Maternal thrombosis & progression to SLE are scarce (Alijotas-Reiget al Autoimmun Rev ‘15)

• IgG fractions from pure obstetric APS display different in vitro effects on monocyte & trophoblast cell ( Lambrianides et al J Immunol ‘10; Poulton et al Am J Reproduct Immunol ‘15)

• Passive transfer of aPL IgG in naive pregnant animals does not need the 2° hit to induce fetal loss (Meroni et al Nat Rev Rheumatol ‘11)

Obstetric vs vascular APS

The evidence of the association with aPL

• aPL & REM: positive association but heterogeneous findings concerning clinical events & laboratory criteria.

• aPL & foetal deaths: sounder association, but still not homogenous reports.

• aPL & PreE or PI: sounder association, but still not homogenous reports

Pathogenic role of aPL in vitro studies

• Proliferation • Syncytialization • Invasion

• Death/apoptosis • Release of trophoblast debries • Inflammatory response

spiral artery remodelling

Pathogenic pathways (Viall & Chamley Autoimmun Rev 2015)

Pathogenic role of aPL in vivo studies

• Passive transfer model (no 2nd hit) • Two different models

Mating 1st week

2nd week

3° week

Sacrifice aPL IgG

50 mg/mouse

(Piona et al Sc J Immunol ’94; Ichikawa et al A&R ’98; Martinez e al PNAS ‘07) Passive infusion model for aPL-mediated fetal loss

Sacrifice aPL IgG

aPL (low amount)-induced fetal loss in pregnant naive C57BL/6 mice: main pathogenic pathways (Martinez del Torre et al J Autoimmun ‘14)

Over-represented biological processes related to differentially expressed genes identified by GO categories enrichment in aPL vs. NHS (filled columns) and aPL vs. aPL þ TIFI (open columns)

comparisons (panel B).

No inflammation in the labyrinth (L) & the junctional zone (jz). A few

leukocytes & focal areas of mild necrosis (**) in the maternal site of placenta (decidua basalis, db), no

difference with controls.

Mating 1st week

2nd week

3° week

Sacrifice aPL IgG

10 mg/mouse

(Holers et al J Immunol ’02; Girardi et al JCI ‘3) Passive infusion model for aPL-mediated fetal loss

Proposed mechanism for the pathogenic effects of antiphospholipid antibodies on tissue injury

Salmon JE et al. (2007) The antiphospholipid syndrome as a disorder initiated by inflammation: implications for the therapy of pregnant patients

Nat Clin Pract Rheumatol 3: 140–147 doi:10.1038/ncprheum0432

C9/TCC

Ctrl

C9/TCC

Ctrl

Figure: C’ deposition

Meroni et al in preparation

20 term placentas ; 2 abortion at 22 WG 5 normal term controls 2 elective abortions at 22 WG Take home messages Mild inflammation/no thrombotic signature Mild complement deposition (till the C9/TCC component) NO relationship with treatment/pregnancy outcome Open questions: Timing of complement damage Role of local complement Few information from plasma levels

0

20

40

60

80

100

120

MBB2 MBB2ΔCH2

Fetal

reso

rptio

n freq

uenc

y (%)

0

0,05

0,1

0,15

0,2

0,25

0,3

0,35

MBB2 MBB2ΔCH2

fetal

weigh

t (g)

P = 0.0008

P = 0.0141

B C C’ non fixing hu anti-DI moAb

C’ + C’ -- C’ + C’ --

C’ non fixing anti-DI hu moAb recognizes murine & human b2GPI but it is not pathogenic (Agostinis et al Blood ‘14)

Flow diagram of our therapeutic approaches to obstetric APS

Chighizola et al Expert Rev. Clin. Immunol. 2014

Efficacy on : • Late >> early pregnancy loss (evidence ++)

• PE (evidence +/-)

• HELLP; IUGR (evidence +)

Safety: thrombocytopenia, osteopenia Peripartum Puerperium (4-6 weeks) Long-term follow up (LDASA treatment)

Heparine: therapeutic effect • Anti-complement activity

Girardi et al Nat Med 2004

2. Heparine: therapeutic effect • Heparin binds b2GPI & displaces the target

antigen for pathogenic aPL (Di Simone et al Arthr Rheum 2010)

3. Heparine: therapeutic effect(s) • Enhances the plasmin-mediated cleavage of Lys317-Thr318

site in b2GPI, resulting in a reduced ability to bind to PLs (Guerin et al J Biol Chem ‘02)

• Protective effect on placental expression of the anti-apoptotic protein Bcl-2 & increased MMP production promoting invasiveness (D’Ippolito et al Autoimmun Rev ‘14)

• Prevents both in vitro & in vivo aPL-inhibited endometrial angiogenesis restoring placental expression of heparin-binding EGF-like growth factor, involved in blastocyst implantation (D’Ippolito et al PLoS One‘12)

• Increase in HLA-G expression (de Carvalho et al Clin Dev Immunol ‘12)

LDASA: therapeutic effect • Placental passage (protective effect on the baby) • Inhibition of the synthesis of thromboxane A2 &

prostaglandin I2 involved in the gestational hypertension & PE (Tulppala et al Human Reproduc ’97)

• Correction of IL-3 reduction (Fishman et al JCI ’93, J Rheumatol ’95, Am J Repr Immunol ’96)

Women with positive aPL do not carry all the same obstetric risk: risk profile

• Double/triple vs single aPL assay positivity • IgG vs IgM isotype • Medium/high titers vs low

LOW TITER AND MEDIUM-HIGH TITER aPL: THE RISK OF OBSTETRIC COMPLICATIONS AND THE EFFECT OF TREATMENT

Chighizola BC, Raimondo MG, Comerio C, Pregnolato F, Sobrino C, Gerosa M, Trespidi L, Acaia B, Ossola W, Meroni PL

University of Milan, IRCCS Ist Auxologico Italiano, ASST G Pini, IRCCS Fondazione Ca Granda

• Conclusions: low titer aPL are significantly associated with aPL-associated obstetric complications, with a lower prevalence of premature birth compared to medium-high titer aPL.

• Treatment with LDASA + LMWH led to a higher increase of live birth rate in women with low titer aPL compared to those with medium-high titer aPL.

• Additional treatment such as HCQ resulted to be effective in women with medium-high titer aPL but not those with low titer aPL.

Pregnant mice: Specific b2GPI signal both in the liver &in the uterus. The uterine signal was localized at the implantation sites, but was undetectable on

the fetuses

Agostinis et al Blood ‘11

IVS IVS Chorionic Villus

FSV

FSV

Chorionic Villus

Anti β2GP-I

Anti β2GP-I

Anti β2GP-I

La Rosa et al J Rheumatol ‘97

Women with positive aPL do not carry all the same obstetric risk: risk profile

Ø Previous thrombosis Ø Previous pregnancy complications Ø Associated autoimmune disorders Ø Uterine & umbelical artery Doppler

velocimetry Ø Complement levels

Risk profile

Chighizola et al Expert Rev. Clin. Immunol. 2014

Refractory patients

• Up to 20% of APS/aPL pos pregnant women display a negative outcome in spite of the treatment with LDASA + Heparin

Flow diagram of our therapeutic approaches to obstetric APS

Chighizola et al Expert Rev. Clin. Immunol. 2014

The rationale behind • IVIg ?? • Corticosteroids (Bramham et al Blood ‘11)

effect on aPL-induced inflammation of decidual and trophblast cells • Plasmapheresis ??

Ruffatti et al Thromb Haemost 2014

HCQ story • Safe in pregnancy (Götestam Skorpen et al ARD ‘16)

• Protective against APS pregnancy complications in the European aPL Forum Registry (Mekinian et al Autoimmun Rev ’15)

• In vitro data aPL binding/AnnexinV displacement aPL inhibition of trophoblast fusion aPL inhibition of IL-6 secretion (Randt et al Blood ‘10; Marchetti et al JTH ‘14; Albert et al Am J Reproduct Immunol ‘14)

0

10

20

30

40

50

60

0 15 30 45 60 75 90

% of

occlu

ded v

esse

ls

Minutes after infusion

IgG aPL+1 + MBB2ΔCH2IgG aPL+1IgG aPL+2 + MBB2ΔCH2IgG aPL+2IgG aPL+3 + MBB2ΔCH2IgG aPL+3

C’ + moAb C’ neg moAb

C’ non fixing anti-DI moAb compets with polyclonal IgG anti-b2GPI

TIFI displaces b2GPI from cell surfaces, inhibiting in vitro binding of FITC-b2GPI to EC & monocytes

§ TIFI: 20 aa synthetic peptide (from CMV) sharing similarity with the b2GPI PL-(membrane) binding region. TIFI binds anionic PL; is not recognized by aPL;

§ TIFI reduced aPL-mediated thrombosis and EC activation in vivo (Vega-Osterta et al Lupus ‘06)

FITC-b2GPI 50 mg/ml + TIFI 20 mg/ml FITC-b2GPI 50 mg/ml + TIFI 5 mg/ml

TIFI reduces anti-b2GPI moAb (IS3) binding to

trophoblast cells (Martinez et al J Autoimmu ‘11) Irr moAb + b2GPI

IS3 + b2GPI

IS3 + TIFI + b2GPI

Anti-b2GPI

PS PS PS

PS

PS PS

PS

PS PS

Syncitium formation and exposure of

phosphatidylserine (PS)

• down-regulation of hCG secretion (at protein and mRNA levels) and matrigel invasiveness in vitro • abnormal trophoblast integrin & cadherin expression • inhibition of proliferation • induction of apoptosis • inhibition of HB-EGF

b2GPI

PS

PS PS PS

PS

PS

TIFI - but not the irrelevant peptide (VITT) – inhibits aPL-induced fetal loss in pregnant naive C57BL/6 mice

Bioimaging

Agostinis et al Blood ‘11

Control with HSA-Cy5.5