Humoral immune responses in healthy heterosexual, homosexual and vasectomized men and in homosexual men with the acquired immune deficiency syndrome.

In homosexual men, the acquired immune deficiency syndrome (AIDS) is associated with sexual promiscuity and the appearance of circulating immune complexes (CICs) and antibodies to spermatozoa which crossreact with lymphoid cells. A comparative study was initiated to determine whether similar humoral responses existed in 38 heterosexual men lacking sperm antibodies, 13 heterosexuals with sperm antibodies, 42 heterosexual vasectomized men, 22 healthy homosexual men, 26 homosexuals with lymphadenopathy and 16 with AIDS or Kaposi's sarcoma (KS). Sperm antibodies were detected in 12% of the vasectomized heterosexual men, 23% of the healthy homosexuals, 35% of the lymphadenopathy patients and 44% of the men with KS-AIDS. IgG reactive with peripheral blood T lymphocytes was present in only 3% of heterosexuals lacking sperm antibody and 5% of vasectomized men. In contrast, 23% of heterosexuals with sperm antibody, 36% of healthy homosexuals, 31% of men with lymphadenopathy and 62% of KS-AIDS patients were positive in this assay. Antibodies to the neutral glycolipid asialo GM1 were found in none of the vasectomized men, 3% of the heterosexuals without and 8% with sperm antibodies, 17% of healthy homosexuals and 38% and 31% in patients with lymphadenopathy or KS-AIDS, respectively. Lastly, the incidence of CICs, determined by the Raji cell assay, was 0% in vasectomized men, 3% in heterosexuals lacking sperm antibody, 31% in heterosexuals with sperm antibody, 69% in healthy homosexuals, 81% in lymphadenopathy patients and 87% in KS-AIDS. In the homosexuals with lymphadenopathy and KS-AIDS, levels of CICs, T cell-reactive IgG and asialo GM1 antibody were positively correlated (p less than 0.01). Sperm antibody levels were negatively correlated (p less than 0.01) with CICs levels and T cell reactive IgG in heterosexuals and lymphadenopathy and KS-AIDS patients. The results demonstrate that vasectomized men do not manifest at all, and that non-vasectomized heterosexuals with sperm antibodies manifest to a much lesser extent the range of humoral immune responses exhibited by the three homosexual groups. Thus, the route of sperm immunization and/or exposure to autologous vs. heterologous spermatozoa may be of critical importance for eliciting specific immune responses.