Localization of a Maturation-Dependent Epididymal Sperm Surface Antigen Recognized by a Monoclonal Antibody Raised against a 135-Kilodalton Protein in Porcine Epididymal Fluid

A specific 135-kDa protein was purified from porcine cauda epididymal fluid. Analysis of its N-terminal amino acid sequence revealed it to be a new protein. Stable clones of hybridomas that produced monoclonal antibodies against the purified 135-kDa protein were established. A clone, B-11, reacting both with epididymal fluid and with sperm plasma membranes was selected and used in this study. Immunoblotting analysis showed that B-11 reacted only with a 135-kDa protein among epididymal fluid proteins