Heparin increases HLA-G levels in primary antiphospholipid syndrome

The treatment of anti-phospholipid syndrome: A comprehensive clinical approach

Anti-phospholipid syndrome (APS) is an acquired pro-thrombotic autoimmune disease that predisposes to thrombotic events and/or obstetric complications, in the persistent presence of anti-phospholipid antibodies (aPL). Life long moderate-intensity anticoagulation is the option of choice for aPL-positive patients with a previous thrombosis; critical issues concern the management of those with a history of arterial event due to the high rate of recurrence. Alternatives comprise anti-platelet agents and high-intensity anticoagulation. Low dose aspirin (LDASA) and low molecular weight heparin provide the mainstay of the treatment of obstetric APS, allowing a birth rate in 70% of cases. The management of refractory APS, thrombotic as well as obstetric, is highly debated, but an increasing burden of evidence points towards the beneficial effects of multiple treatments. Similarly, a management envisaging multiple drugs (anticoagulation, steroids, plasma exchange and/or intravenous immunoglobulins) is the most effective approach in catastrophic APS. Asymptomatic aPL carriers are at higher risk of thrombotic and obstetric complications compared to the general population, thus potentially benefitting of a pharmacological intervention. LDASA and hydroxychloroquine can be considered as options, in particular in case of high risk aPL profile, concomitant cardiovascular risk factors or associated autoimmune disease. APS is apparently a simple condition, but its multifaceted nature requires a complex and tailored treatment.

Soluble HLA-G in pregnancies complicated by autoimmune rheumatic diseases

Autoimmune rheumatic diseases in pregnancies are associated with increased adverse obstetric outcomes. We compared maternal soluble human leucocyte antigen-G (sHLA-G) blood levels in subjects with a rheumatic disease preexisting pregnancy and unaffected controls. Third-trimester blood maternal sHLA-G concentrations were significantly higher in subjects with rheumatic diseases than in controls (mean 93.1ng/ml [SD 42.1] vs 58.1ng/ml [SD 96.3], p=0.003). Cord blood sHLA-G concentrations were significantly higher in rheumatic disease than in those born to control mothers (median 41.2ng/ml [IQR: 3.3-44.0] vs 17.9ng/ml [IQR: 17.2-88.1], p=0.007). A strict positive correlation (r=0.88, p<0.001) was found between the maternal and fetal titers of ANA autoantibodies as well as between maternal and fetal sHLAG circulating levels (r=0.58 and r=0.67, respectively, for controls and cases, p<0.001). Maternal s-HLA-G blood concentrations were significantly higher in subjects with rheumatic disease DEL/DEL homozygous for a polymorphism of the 3' untranslated regulatory region of HLA-G (HLA-G 14bp) than in the corresponding healthy controls (mean values 141.5ng/ml [SD: 166] vs 54.2ng/ml [SD: 35], p=0.009). Increasing maternal and cord blood levels of s-HLA-G concentrations among pregnant subjects with rheumatic diseases compared with controls suggest that autoimmune diseases prompt a maternal and fetal immune response that favors pregnancy immune tolerance.