Experimental autoimmune prostatitis after neonatal thymectomy in the mouse.

Experimental autoimmune prostatitis (EAP) could be induced in (C3H/HeMs X 129/J)F1 mice by thymectomy (Tx) at 3 days (Tx-3) but not at 0 or 7 days after birth. Appearance of EAP was noticed in the three lobes of the prostate, most frequently and severely in the anterior lobe (coagulating gland). EAP thus induced was characterized by a loss of secretory products in the lumen, massive lymphocytic infiltration in the stroma, especially beneath the epithelial cells, and by the presence of circulating autoantibody(ies) against the epithelial cells of the prostate (APA). EAP started at puberty and its incidence was 68% in 50-150 day old mice. APA was completely absorbed with the homogenates of prostate but not of seminal vesicles, testes or livers of the mouse. High titres of APA, detectable in sera of more than 1,000-fold dilutions accompanized with the severe lesion, were assayed by indirect immunofluorescence (IFL) technique. No sign of EAP was seen in the immature prostate of 90 day old mice which were orchidectomized at 0 day (Orx-0) followed by Tx-3. Exogenous androgen treatment at an adult age induced EAP in these Orx-0 plus Tx-3 mice. The findings indicate that mice which received Tx at a critical neonatal age develop EAP by autosensitization to the antigen(s) normally expressing in the differentiated prostate.