EFFECT OF BOAR SEMINAL IMMUNOSUPPRESSIVE FRACTION ON B-LYMPHOCYTES AND ON PRIMARY ANTIBODY-RESPONSE

Repeated i.p. or rectal treatment of male and female mice with an immu nosuppressive component isolated from boar seminal vesicle secretion r educed responses of B lymphocytes to mitogen as evaluated by [H-3]thym idine or bromo-deoxyuridine incorporation. The proliferative activity of T lymphocytes was not affected. By means of the immunofluorescence method, the seminal immunosuppressive component was detected on the me mbranes of B lymphocytes separated from the spleens of mice treated in vivo with immunosuppressor. An i.p. injection or rectal infusion of t he immunosuppressive component also led to a suppression of primary an tibody response to soluble and particulate antigens. These findings in dicate that in vivo deposition of semen may compromise some aspects of the immune system and may be an important cofactor in the development of viral and bacterial infections in homosexual men.