[Heterogeneity of sperm immobilizing antibodies in sera of sterile women].

Among 126 sterile women, 8 patients indicated sperm immobilizing (SI) antibodies in their sera, while 13 and 57 patients showed positive results in sperm agglutination (SA) test and indirect immunofluorescence (IF) tests, respectively. These results suggest that the antisperm antibodies detected by different methods are not identical and seem to be raised to different epitopes of sperm antigens. SI antibodies were absorbed not only with human spermatozoa, but also with human seminal plasma (HSP) in most patients. When each patient's serum was absorbed with a certain amount of different HSP specimens from donors, the remaining SI activities of the antibodies were different. When SI antibodies in patients' sera were absorbed with periodic acid-treated or mixed glycosidase-treated human spermatozoa, some patients' sera were absorbed, while other patients' sera were not absorbed, but non-treated spermatozoa absorbed the antibody activities completely in all patients' sera. These results suggest that there were different characteristics in the specificity of SI antibodies in patients' sera, and that SI antibodies in some patients were raised to carbohydrate antigen epitopes on human spermatozoa.