ブタ血小板膜糖蛋白Ｉ ｂおよびＩＩ ｂ／ＩＩＩ ａに対するモノクローナル抗体の作製

Abstract

We have prepared murine monoclonal antibodies to porcine platelet glycoprotein (GP) Ib and GPIIb/IIIa for further study of the porcine hemostatic mechanism. One monoclonal antibody, designated PP3-4C, blocked ristocetin-induced platelet agglutination and caused 80% inhibition of ristocetin-induced 125I von Willebrand factor (vWF) binding to platelets at a concentration of 12μg IgG/ml. Another monclonal antobody, designated PP3-3A, completely inhibited ADP- or collagen-induced platelet aggregation at 6μg IgG/ml. At a concentration of 10μg IgG/ml PP3-3A completely inhibited binding either of 125I-fibrinogen or of 125I-vWF to ADP-stimulated platelets. Immunoaffinity chromatography of solubilized surface-radiolabeled porcine platelets and subsequent SDS-polyacrylamide gel electrophoresis demonstrated that PP3-4C recognized a glycoprotein with an apparent molecular weight of 160, 000 (non-reduced), and 140, 000 (reduced). PP3-3A recognized glycoproteins with apparent molecular weights of 130, 000 and 80, 000 (non-reduced), and 115, 000 and 100, 000 (reduced). These monoclonal antibodies to porcine platelet membrane glycoproteins which are structural and functional analogues of human GPIb and GPIIb/IIIa will be useful for in vitro and in vivo studies of the mammalian hemostatic mechanism.