The effect of antibody against a purified sperm-coating antigen on human sperm

A purified fraction of human seminal plasma containing a sperm-coating antigen and two minor contaminants was used to immunize rabbits by intravenous route. An antiserum containing only the antibody against the sperm-coating antigen as examined by immunoelectrophoresis was obtained from one rabbit. The effect of this antiserum on human sperm was examined by sperm-immobilization and sperm-agglutination tests. The results revealed that the antibody against the purified sperm-coating antigen was incapable of immobilzing or agglutinating human sperm. This indicates that the purified sperm-coating antigen is unlikely to be useful as an antifertility antigen for immunologic fertility control.