Sperm autoantigens recognized by autoantibodies in developing rats following prepubertal obstruction of the vas deferens.

Sperm protein autoantigens recognized by serum antisperm autoantibodies during development following vas deferens obstruction were studied using western blot analysis. At age 10 days, rats in an obstructed group underwent bilateral ligation and division of the vas deferens, whereas animals assigned to a sham group received a sham operation. At ages 14, 21, 35, 56, 91, and 128 days, rats were sacrificed and blood samples were obtained. Sperm antigens were recognized infrequently and with low intensity by most sera obtained at ages 14 through 56 days. Subsequently, the incidence as well as the intensity of staining of antigens in blots increased at 91- and 128-day intervals in obstructed animals. The increase in antisperm antibodies correlated with the appearance of sperm throughout the epididymis at approximately 56 days postnatally. A set of autoantigens including proteins migrating at 82-78, 76-73, 68, 57, 54, 48, 44, 42, 38-42, 36, and 22 kDa were recognized with the highest frequency and intensity after puberty. A 42-kDa protein appeared to be one of the first autoantigens recognized when obstructed animals underwent sexual maturation. Although individual animals recognized different patterns of sperm autoantigens, a repertoire of 10-12 autoantigens dominated the antisperm antibody response when obstructed animals underwent sexual maturation.