Monoclonal antibodies to rabbit sperm autoantigens. II. Inhibition of human sperm penetration of zona-free hamster eggs.
Monoclonal antibodies (mAbs) to the rabbit sperm autoantigens RSA-1, 2 and 3 were found to cross-react with human ejaculated spermatozoa. The mAbs show by indirect immunofluorescent staining that the antigen is concentrated in the middle-piece region of the tail, with lesser amounts on the head region. Binding of mAbs to human sperm extract was 75% of the maximum binding to rabbit spermatozoa. Immunoadsorbent chromatography and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) identified three sperm antigens of 87,000, 15,000 and 13,000 daltons (kd). The mAbs significantly inhibited human spermatozoa from penetrating zona-free hamster oocytes. It is concluded that human sperm, like rabbit sperm, may have a low molecular weight family of membrane glycoproteins with a higher molecular weight extrinsic protein bound together in a complex on their surfaces.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis*; D000941:Antigens / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D006224:Cricetinae; D003429:Cross Reactions; D000939:Epitopes / Q000276:immunology; D005260:Female; D005306:Fertilization; D005307:Fertilization in Vitro; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D008647:Mesocricetus; D013075:Sperm Capacitation; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000941:Antigens; D001324:Autoantigens; D000939:Epitopes