Problem: The involvement of individual sperm proteins in differentiation of antigenically specific and functionally defined regions on sperm membrane has not yet been completely elucidated.
Method: BALB/c mice were immunized with live capacitated boar spermatozoa and used for production of monoclonal antibodies (MAbs). ELISA, IIF, SDS-PAGE, IVF, and cytologic methods were used for selection and biological characterization of MAbs as well as for identification of corresponding antigens.
Results: MAb1F10, MAb2E2, and MAb4B12 react with antigens in the acrosome portion of live capacitated spermatozoa, MAb 1F10 reacted with human sperm cells along with those from bull, ram, mouse, dog, whereas MAb2E2--with mouse's spermatozoa and MAB4B12-with bull's, mouse's, and dog's spermatozoa. Some glycolytic enzymes seemed to reduce mildly the reactions of the MAbs with enzyme treated sperm cells; proteolytic enzymes eliminated the binding of MAbs to the sperm acrosome. These MAbs have no sperm agglutinating and/or sperm-immobilizing activities and reduced the number of spermatozoa binding to zona pellucida.
Conclusions: MAb1F10, MAb2E2, and MAb4B12 seemed to recognize membrane associated antigens with potential role in the initial stages of fertilization, specific for capacitated but not for freshly ejaculated spermatozoa.