Human Von Willebrand Factor (factor VIII R: Ag) is a 270 kDa multimeric plasma gylcoprotein. Important in the maintenance of hemostasis, it mediates platelet adhesion to injured vessel walls and serves as a carrier and stabilizer for coagulation factor VIII. The Von Willebrand factor has functional binding domains to platelet glycoprotein Ib, glycoprotein IIb/IIIa, collagen and heparin. The factor is synthesized by endothelial cells and is also present in platelets and megakaryocytes.
