Immunochemical studies of the purified human platelet receptor for the alpha 1(I)-chain of chick skin collagen.
The membrane receptor of human platelets that binds the alpha 1(I)-chain of chick skin collagen was purified to homogeneity by molecular sieve chromatography, affinity chromatography, and preparative gel-electrophoresis. Rabbits that were immunized with the purified receptor emulsified in complete Freund's adjuvant produced antibody, as measured by an enzyme-linked immunosorbent assay. The antiserum was shown to be highly receptor-specific by immunoprecipitation of solubilized platelet membrane protein that had been labeled with (gamma-32P)ATP and protein kinase. Platelet aggregation induced by alpha 1(I) as well as native chick skin collagen was inhibited by both the purified receptor and antibody against the receptor in a dose-dependent fashion. In contrast, neither the receptor nor the antiserum inhibited ADP-induced aggregation. These studies provide the most definitive evidence that alpha 1(I) and native collagen interact specifically with a cell surface receptor on human platelets to induce aggregation.
D000818:Animals; D000918:Antibody Specificity; D001667:Binding, Competitive; D001792:Blood Platelets / Q000378:metabolism* / Q000502:physiology; D002645:Chickens; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D003094:Collagen / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007106:Immune Sera / Q000302:isolation & purification / Q000494:pharmacology; D010974:Platelet Aggregation; D011817:Rabbits; D011956:Receptors, Cell Surface / Q000276:immunology / Q000302:isolation & purification*; D038981:Receptors, Collagen; D012867:Skin / Q000378:metabolism*
D007106:Immune Sera; D011956:Receptors, Cell Surface; D038981:Receptors, Collagen; D003094:Collagen