Von Willebrand Factor and ADAMTS13

Von Willebrand factor (VWF) promotes platelet adhesion and aggregation at sites of vascular injury and serves as a carrier for coagulation factor VIII. The activity of VWF is modulated by ADAMTS13 (a disintegrin and metalloprotease with thrombospondin motif repeats 13), a metalloprotease that cleaves highly procoagulant, ultralarge VWF multimers into smaller, less procoagulant forms. Deficiency for VWF quantity or activity results in the bleeding disorder von Willebrand disease, whereas severe deficiency in ADAMTS13 results in the clotting disorder thrombotic thrombocytopenic purpura.See accompanying article on page 2446 Since the identification of ADAMTS13 as the VWF cleaving protease in 20011 and the recognition that severe ADAMTS13 deficiency is associated with thrombotic thrombocytopenic purpura, several case control studies have looked for connections between specific disease risk and partial ADAMTS13 deficiency.2 Likewise, reduced levels of ADAMTS13 have been associated prospectively with an increased risk of coronary artery disease3,4 and ischemic stroke.5 …