RESISTANCE OF FEMALE GUINEA-PIG FERTILITY TO EFFICIENT ISOIMMUNIZATION WITH SPERMATOZOA AUTO-ANTIGENS

Virgin female guinea pigs received two courses of immunization with S, P or T spermatozoa autoantigens and Freund's complete adjuvant and were mated from 1 up to 18 weeks after the end of each course. The immunizations were efficient as judged by the titers of circulating antibodies to S, P or T, the existence of antibodies to the corresponding immunizing antigen in cervico-vaginal secretions and by cutaneous reactions of delayed hypersensitivity. In spite of this successful immunization, the fertility rate was 100% after the first course and only slightly decreased after the second one. The only significant events were a delay in the time of fertilization and a high rate of intrauterine death (as already observed following anti-S immunization). The absence of fertility impairment was not due to a lack of a relevant antigen in the injected preparations since immunizing female guinea pigs with either epididymal spermatozoa or crude water-soluble extract also did not decrease the fertility. The mechanisms responsible for such a resistance remain to be elucidated; they may involve spermatozoa coating substances, enhancing antibodies or sperm immunosuppressive factors. © 1979.