The fate of acrosomal staining during the acrosome reaction of human spermatozoa as revealed by a monoclonal antibody and PNA-lectin.
A monoclonal anti-human sperm antibody, raised against an acrosomal antigen and indicated to recognize in boar sperm the serine protease, acrosin, stained in human spermatozoa a 50 Kd antigen and several others in the region 24-34 Kd by immunoblotting. The 50 Kd band and the region of 30-34 Kd showed proteolytic activity by zymographic enzyme detection. The fate of the antigen was studied in the acrosome reaction induced by the calcium ionophore A23187. In control incubations 69.5 +/- 14.2% (mean +/- SD) of the spermatozoa had intact acrosomal staining according to indirect immunofluorescence using this antibody whereas in acrosome-reacted samples only 21.0 +/- 2.0% of the sperm were stained. Another marker for the acrosome, peanut agglutinin-lectin (PNA), was used to detect the acrosome with similar results. Acrosome reactions were verified by electron microscopy. The present results indicate that the corresponding antigen, evidently acrosin, and PNA-positive material are liberated during the acrosome reaction which suggests that they are not bound to the inner acrosomal membrane but are components of the acrosomal matrix.
D000176:Acrosin / Q000276:immunology; D000177:Acrosome / Q000276:immunology / Q000502:physiology* / Q000648:ultrastructure; D000911:Antibodies, Monoclonal; D000941:Antigens / Q000276:immunology; D000001:Calcimycin / Q000494:pharmacology; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins; D005455:Fluorescent Antibody Technique; D005456:Fluorescent Dyes; D006801:Humans; D007159:Immunologic Tests; D037102:Lectins; D008297:Male; D008854:Microscopy, Electron; D019887:Peanut Agglutinin; D013094:Spermatozoa / Q000502:physiology* / Q000648:ultrastructure*; D013861:Thiocyanates
D000911:Antibodies, Monoclonal; D000941:Antigens; D005452:Fluoresceins; D005456:Fluorescent Dyes; D037102:Lectins; D019887:Peanut Agglutinin; D013861:Thiocyanates; D000001:Calcimycin; D000176:Acrosin; D016650:Fluorescein-5-isothiocyanate