title: Studies of the human factor VIII/von Willebrand factor protein. III. Qualitative defects in von Willebrand's disease.
abstract: The Factor VIII/von Willebrand factor protein was characterized in two unrelated patients with von Willebrand's disease in whom procoagulant and Factor VIII/von Willebrand factor antigen levels were normal. In both patients evidence of an abnormal protein was observed on crossed antigen-antibody electrophoresis. In one patient the Factor VIII/von Willebrand factor protein eluted from Sepharose 4B in a position and distribution identical to normal with normal levels of procoagulant activity and antigen. However, the partially purified Factor VIII/von Willebrand factor protein had markedly reduced von Willebrand factor activity in a ristocetin assay. In the second patient the peak of Factor VIII/von Willebrand factor protein, antigen, and procoagulant activity eluted from a Sepharose 4B column with an estimated molecular weight of approximately half that of normal. This protein had no von Willebrand factor activity. In both patients the reduced Factor VIII/von Willebrand factor protein subunit was indistinguishable from normal on polyacrylamide gel electrophoresis. These studies indicate that in some patients with von Willebrand's disease there is a qualitative defect of the Factor VII/von Willebrand factor protein; the total amount of protein, antigen, and procoagulant activity are normal while the von Willebrand factor activity is deficient.
mesh_terms: D000906:Antibodies; D000941:Antigens; D001780:Blood Coagulation Tests; D011232:Chemical Precipitation; D002850:Chromatography, Gel; D002918:Chymotrypsin; D020147:Coagulation Protein Disorders; D003378:Counterimmunoelectrophoresis; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006467:Hemophilia A / Q000276:immunology*; D006801:Humans; D008297:Male; D010973:Platelet Adhesiveness; D010974:Platelet Aggregation / Q000187:drug effects; D012310:Ristocetin / Q000494:pharmacology; D014842:von Willebrand Diseases / Q000097:blood* / Q000235:genetics
chemical_list: D000906:Antibodies; D000941:Antigens; D012310:Ristocetin; D005340:Fibrinogen; D002918:Chymotrypsin