Seminal plasma antigens detected by immunoblotting with human sera from vasectomized males

Eighty-seven serum samples from vasectomized men and 10 samples from normal men were analyzed by immunoblotting for auto-antibodies against seminal plasma proteins. Auto-antibodies against seminal plasma were present in 53 out of 87 vasectomy serum samples. Seminal plasma electrophoresed under non-reduced conditions revealed major antigens at 35 and 68 kDa recognized by auto-antibodies. Whereas under reduced conditions auto-antibodies recognized to a variable degree many more antigens having apparent molecular weights of 20, 22, 35, 40, 45, 65, 68, 70 and 75 kDa. None of the sera reacted only with reduced or non-reduced samples. The results of sperm agglutination and sperm immobilization tests correlated with no specific molecular weight antigen. Many of the recognized antigens were glycoprotein. The reactivity of the auto-antibody to the seminal plasma antigens is specific and could not be blocked by prior adsorption of the serum samples with liver powder or human sperm.