Differences in the antigen pattern recognized by antisperm antibodies in patients with infertility and vasectomy

Purpose: Antisperm antibodies may impair sperm fertilizing capacity. They a re found in infertile patients and in men after vasectomy. Little is known to date of the biochemical nature of the antigens that induce the productio n of antisperm. antibodies. Materials and Methods: Sperm membrane proteins were prepared from donor spe rmatozoa, separated by 1-dimensional polyacrylamide gel electrophoresis and exposed to seminal plasma samples of 36 infertile men and 34 after vasecto my containing antisperm antibodies. Results: Ten antigenic protein bands with different molecular weight were r ecognized by antisperm antibodies. Antisperm antibodies binding to the anti gen band at 55 kDa. were significantly more common in infertile men, while those binding to the 72 kDa. band were more common after vasectomy. Signifi cant differences also occurred in the incidence of detecting the 55 kDa. an tigen band by the antisperm antibodies of patients with and without varicoc ele. Comparing antisperm antibodies from patients with or without a history of genital diseases or trauma did not reveal significant differences in th e antigens detected. Conclusions: It seems likely that the development of antisperm antibody bin ding to different antigens is related to the mode of antibody induction. Si nce the antigenic properties of spermatozoa change during passage through t he epididymis, the antigens detected by antisperin antibodies from men with vasectomy are mostly related to epididymal passage. The identification of human sperm antigens is essential for understanding the mechanism by which antisperm antibodies influence the fertilization capacity of spermatozoa. I t is also necessary for the potential development of reliable diagnostic me thods for antisperm antibodies that are relevant to infertility.