Properties of a Monoclonal Antibody Interacting with Human Sperm

Abstract
A monoclonal antibody (MAB) interacting with human sperm was purified by ammonium sulfate fractionation and gel filtration on Sephadex G-200. The MAB designated as YWK-II belongs to the IgM class and is composed of μ heavy chains and κ light chains. The MAB localized to the equatorial region of the sperm head, midpiece, and tail. The sperm antigen interacting with the YWK-II MAB was purified by immunoaffinity chromatography on Sepharose 4B conjugated with YWK-II antibodies. Two interacting proteins, estimated Mr of 60 and 72 kD, were identified.