Identification of mammalian sperm surface antigens: II. Characterization of an acrosomal cap protein and a tail protein using monoclonal anti-mouse sperm antibodies

Monoclonal anti-mouse sperm antibodies have been produced by fusing mouse myeloma cells with spleen cells from rats immunized with epididymal sperm of C3H mice. Immunoprecipitation and immunoperoxidase techniques showed that one such monoclonal antibody, AMS IV-33, recognized a 200 000 dalton protein localized on the acrosomal cap of the sperm cell. Two other monoclonal antibodies AMS IV-54 and -76, reacted with a 68 000 dalton component on the surface of the sperm tail. Both antigenic targets were species specific and were present in about equal amounts on sperm from several different strains of mice. The tail protein was sperm specific, whereas the antibody reacting with the acrosomal cap protein also appeared to react somewhat with antigens present in other mouse tissues.