TEMPORAL RECOGNITION OF SPERM AUTOANTIGENS BY IGM AND IGG AUTOANTIBODIES AFTER VASECTOMY AND VASOVASOSTOMY

Temporal patterns of IgM and IgG autoantibodies to sperm proteins were studied by western blot analysis at intervals after bilateral vasecto my, vasectomy followed one month later by vasovasostomy, or sham opera tions. Responses were detected to eight major autoantigens at 21-23, 3 6, 41, 51, 57, 63, 68-71 and 75-83 kDa, by study of staining patterns of sequential serum samples from individual animals and by analysis of the incidence of reaction to each protein. The four lower molecular w eight antigens (21-23, 36, 41 and 51 kDa) provoked mainly Ige response s. The strongly stained set of higher molecular weight antigens (57, 6 3, 68-71 and 75-83 kDa) tended to show more clearly defined temporal p atterns of IgM followed by IgG response, including a high incidence of IgM antibody at the 2-week interval. Three of the larger peptides (57 , 63 and 68-71 kDa) appeared highly immunogenic, since some reactions were detected even in sham-operated rats. The classical patterns of Ig M and IgG antibody responses to the majority of the dominant sperm aut oantigens are in accord with the hypothesis that vasectomy mimics immu nization with spermatozoa. The high incidence of IgM antibodies in the earliest sample, taken 2 weeks after vasectomy, suggests that the ini tial immunizing event takes place within about a week after the operat ion. Vasovasostomy did not bring about a decrease in antisperm antibod ies. Instead, some animals demonstrated an increased reaction to certa in antigens after reversal of vasectomy, even though the vasovasostomi es were anatomically successful.