von Willebrand factor is an adhesive glycoprotein critical to normal hemostasis. It is stored in the Weibel-Palade body of endothelial cells and upon release may mediate platelet adhesion. Herpesvirus-infected endothelium is known to be prothrombotic and to support enhanced platelet adherence. We previously identified P-selectin as a monocyte receptor that is translocated from the Weibel-Palade...

Blood Transfus 2011; 9 Suppl 2:s3-s8 DOI 10.2450/2011.002S © SIMTI Servizi Srl von Willebrand factor (VWF) is an adhesive and multimeric glycoprotein that found its historical origin in 1924, when the Finnish physician Erik von Willebrand first reported a family with a serious hereditary bleeding affecting consanguineous families. The proband was a five years old girl with severe bleeding since...

Von Willebrand disease (VWD) is the common autosomal bleeding disorder caused by a quantitative and/ or qualitative defect in the Von Willebrand Factor (VWF), a large multimeric multifunctional plasma glycoprotein which plays a critical role in hemostasis. It is essential for platelet adhesion to damaged endothelium as well as platelet interactions at high shear stress. VWF has a direct role in...

Von Willebrand disease (VWD) is the common autosomal bleeding disorder caused by a quantitative and/ or qualitative defect in the Von Willebrand Factor (VWF), a large multimeric multifunctional plasma glycoprotein which plays a critical role in hemostasis. It is essential for platelet adhesion to damaged endothelium as well as platelet interactions at high shear stress. VWF has a direct role in...

We have examined the multimeric composition of factor VIII/von Willebrand factor in plasma and platelet lysates by means of sodium dodecyl sulfate agarose electrophoresis followed by staining with (125)I-labeled affinity-purified antibody. In normal plasma and platelet lysates, factor VIII/von Willebrand factor displayed 10 distinct multimers that ranged in apparent molecular weight from 0.86 t...

A modification of Salzman's method has been used in an attempt to provide an assay in vitro for the von Willebrand factor. Platelet adhesiveness was increased in von Willebrand's disease by previously coating the beads with normal or haemophilic plasma or cryoprecipitate, whereas von Willebrand plasma had no corrective effect. Antihaemophilic factor (AHF) concentrates were studied in the same w...

Von-Willebrand disease (VWD) is one of the platelet dysfunction disorders that results from a deficiency of Von-Willebrand factor, which is essential for hemostasis. VWD patients typically have normal laboratory results on screening for bleeding disorders. To suspect and diagnose VWD, a careful review of past medical history and laboratory tests is critical. A 59-year-old male patient presented...

Pseudo (platelet-type)-von Willebrand disease is an autosomal dominant bleeding disorder caused by the hyperfunction of a receptor on the platelet surface. The abnormal receptor, glycoprotein Ib, displays increased affinity for its ligand, von Willebrand factor. Four members (normal mother/affected father/two affected daughters) of a family with pseudo-von Willebrand disease were studied to det...

Platelet thrombus formation occurs at sites of severe arterial narrowing where shear stress is elevated. Shear stress appears to induce platelet aggregation in vitro by means of initiation of von Willebrand factor binding to platelet glycoprotein lb. Recent in vitro studies have demonstrated that aurintricarboxylic acid can inhibit shear stress-induced platelet aggregation. This effect is media...