Lymphocyte proliferative response to fertilization antigen in patients with antisperm antibodies

The fertilization antigen, immunopurified from human testes, activated lymphocytes from three of the six men and women with antisperm antibodies. Lymphocytes from none of the six men and women without antibodies were activated with fertilization antigen. Another sperm surface antigen, the germ cell antigen, immunopurified from murine testes, did not activate lymphocytes from any of the individuals with or without antisperm antibodies. These results indicate that the men and women with antisperm antibodies are sensitized against fertilization antigen and not germ cell antigen. These results reinforce our previous findings on the involvement of fertilization antigen in immunoinfertility in humans.