von Willebrand Factor Antibody / vWF

Human von Willebrand factor (VWF or factor VIII-related antigen) is a 309 kDa multimeric plasma glycoprotein, important in the maintenance of hemostasis, it promotes adhesion of platelets to the sites of vascular injury by forming a molecular bridge between sub-endothelial collagen matrix and platelet-surface receptor complex GPIb-IX-V. Von Willebrand factor also acts as a chaperone for coagulation factor VIII, delivering it to the site of injury, stabilizing its heterodimeric structure and protecting it from premature clearance from plasma. Von Willebrand factor is synthesized by endothelial cells and is reported to be expressed in a number of tumors of vascular origin. IHC results aid in the classification of acute myeloid leukemia FAB type M7, angiosarcoma and epithelioid hemangioendothelioma.