Sperm and seminal plasma antigens from autoimmune men induce immunological infertility

Adult male rabbits were immunized with normal saline (controls), sperm extracts from 2 autoimmune men, seminal plasmas from the same autoimmune men, sperm extract from a fertile nonautoimmune man, and seminal plasma from the same fertile nonautoimmune man. All the sperm donors were free from infections. Rabbits immunized with fertile men's sperm extract and seminal plasma had significantly elevated postimmunization hemagglutinating but not cytotoxic sperm antibodies and reproduced normally. Rabbits immunized with autoimmune men's sperm and seminal plasma antigens developed high titers of cytotoxic and hemagglutinating sperm antibodies in their serum and seminal plasma and their reproduction was markedly reduced. Their sera and seminal plasma reduced motility of sperm from a normal donor. The immune responses were confirmed by electron microscopic immunocyto-chemistry. This technique revealed membrane-bound endogenous IgG on sperm from only those rabbits immunized with sperm extracts from autoimmune men. T...