title: Type IIB von Willebrand disease: a paradox explains how von Willebrand factor works.
abstract: Type IIB is a variant form of von Willebrand disease in which a structural abnormality of von Willebrand factor (VWF) causes enhanced binding to the platelet glycoprotein Ib receptor. As a consequence of this functional alteration, there is a decrease in the concentration of the largest VWF multimers in plasma, and the platelet count may be episodically decreased as a consequence of microaggregation. The net result is an apparent paradox, since the presence of a hyperfunctional adhesive molecule in blood causes a bleeding tendency. Here I recall how my colleagues and I managed to understand what goes on in these patients.
authors.affiliation: Roon Center for Arteriosclerosis and Thrombosis, Division of Experimental Hemostasis and Thrombosis, Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA. ruggeri@scripps.edu
authors.forename: Z M
authors.initials: ZM
authors.lastname: Ruggeri
mesh_terms: D014644:Genetic Variation; D049673:History, 20th Century; D006801:Humans; D014842:von Willebrand Diseases / Q000097:blood / Q000209:etiology / Q000266:history*; D014841:von Willebrand Factor / Q000235:genetics / Q000266:history* / Q000502:physiology
chemical_list: D014841:von Willebrand Factor