Sperm-immobilizing antibody and its target antigen (CD52)

Abstract

Complement-dependent sperm-immobilizing antibodies (SI-Abs) are exclusively detected in the serum of infertile women. We generated a number of sperm-immobilizing monoclonal antibodies to examine antigenic epitopes for SI-Abs. The epitope for Mab H6-3C4, a human monoclonal antibody generated from peripheral B lymphocytes of a patient with strong SI-Abs was found to be present in the carbohydrate moieties of CD52. CD52 is known as a glycosylphosphatidylinositol (GPI) anchor glycoprotein present in lymphocytes and male reproductive tracts (mrt) including mature sperm and seminal plasma. However, the immunochemical property of mrt-CD52 is different from that of CD52 in the lymphocytes. In this article, biological and immunological functions of mrt-CD52 epitope analyses for different monoclonal antibodies reactive to mrt-CD52 are described. © 2009 Springer-Verlag Berlin Heidelberg.