Effects of vasectomy and antisperm antibodies on human seminal fluid deoxyribonucleic acid polymerase activity

DNA-synthesizing complexes possessing a sucrose buoyant density of 1.24 to 1.25 gm/ml were identified in cell-free human seminal fluids prior to and 1 to 3 months following division of the vasa deferentia, performed for fertility control in otherwise normal males. After vasectomy, there was a 3.5-fold decrease in endogenous DNA polymerase activity per ejaculate. Partial purification of the seminal fluid DNA polymerase by gel filtration revealed a similar 3.5-fold decrease in dT12--18-poly (rA)-templated DNA polymerase activity postvasectomy. Immunoglobulin G, isolated from a rabbit immunized with nuclei derived from detergent-treated ejaculated human spermatozoa, inhibited both sperm- and seminal fluid-derived DNA polymerase activity. The decrease in seminal fluid enzyme activity following vasectomy might be due to its inhibition by sperm autoantibodies induced after vas division.