Platelet-Derived Microvesicles Reverse The Lupus Anticoagulant Effect And Are More Potent Then Synthetic Phospholipids In Supporting Thrombin Generation In Antiphospholipid Syndrome

Background: Antiphospholipid Syndrome (APS) is associated with clinical thrombosis manifestations. However, it is characterized as prolongation of lag time in phospholipid (PL) dependent laboratory coagulation assays, a reflection of the paradoxical lupus anticoagulant (LAC) effect. In contrast to clinical laboratory testing which almost exclusively utilize synthetic PL (sPL), activated platelets are a major source for PL for in vivo hemostasis. It was recently reported that platelet-derived microvesicles (P-MVs) release is mediated by a positive thrombin generation feedback loop in the process of platelet activation and membrane ballooning, which supports a physiological role for P-MVs in hemostasis (Agbani, et. al., 2017).