Molecular dissection of human testicular germ cell differentiation with monoclonal antibodies.

Monoclonal antibodies (MoAbs) were raised by immunising mice with nucleated cells other than sperm (NCOS) obtained from semen of an oligospermic donor. These MoAbs recognised different germ cell differentiation antigens (GDA) which appear at various stages of spermatogenesis and/or spermiogenesis. The GDA were found to be differentially expressed on spermatocytes, spermatids and on the various sub-regions of human spermatozoe. Some of the MoAbs also recognised changes in the antigenic structure of the sperm during their post-testicular maturation. Using solubilised sperm products, MoAb GDA-J/F1 reacted with a 92 kDa band in Western immunoblotting. The importance of these antibodies in the study of germ cell differentiation together with their potential clinical uses in the investigation of infertility, autoimmunity and immunological contraception are discussed.