Comparison of allergic aspermatogenesis with that induced by vasectomy. I. In vivo studies in the guinea-pig.

Groups of male and female guinea-pigs were immunized with homologous epdidymal sperm in Freund's complete adjuvant (FCA) and skin tested at weekly intervals with a heat-treated extract of the sperm or with PPD. In females, the skin response to both antigens was similar to that to any standard protein antigen. In males, the response to sperm extract varied with the induced auto-immune orchitis, reaching a maximum immediately after testis lesion was most severe and as recovery was beginning (shown histologically): the response to PPD was decreased at 1 week after immunization, but subsequently was similar to that in females. Skin tests on guinea-pigs 8 months after bilateral vasectomy (when both ends of vasa were ligated), showed no evidence of delayed hypersensitivity to sperm, although there was marked histological evidence of reduced spermatognesis, due to back pressure atrophy.