The Role of Platelet Surface Proteins Reacting with Heterologous Antibodies

Abstract
Platelets were labelled with surface-labelling agents which identified up to six platelet membrane proteins. Three of these labelled proteins were recognised by a specific anti-platelet membrane serum by immunoprecipitation. Affinity fractionation of platelets with insolubilised IgG obtained from the anti-platelet membrane serum indicated a greater reaction between the antiserum and the platelet surface. Fab fragments from the antiserum inhibited ristocetin-induced aggregation of platelets and partially inhibited collagen-induced aggregation but did not affect ADP aggregation. Crossed immunoelectrophoresis of platelets using the anti-platelet membrane serum showed that the antiserum was specific for platelet membranes.