Histopathological and immune-pathological changes in the prostates of golden hamsters experimentally infected with schistosoma mansoni

ABSTRACT

This work has been planned to study the histopathological and immune-pathological changes in the prostates of experimentally infected golden hamsters with Schistosoma mansoni. Fifty male golden hamsters, 10 weeks old, 200-250 gm in weight each and free from parasitic infections were used. They were classified into two groups. Group [1] 40 male golden hamsters infected with 350 S. mansoni cercariae S.C. each. Group [2] 10 male golden hamsters [control]. Viable S. mansoni eggs were collected, washed and egg hatching was performed. Biomphalaria alexandrina snails were infected by 6 - 8 miracidia each. The released cercariae were collected, counted and concentrated so as to contain 350 cercariae / 0.5 ml. [the infective dose / hamster S. C.]. Five infected hamsters were killed 6, 8, 10, 12, 14, 16, 18 and 20 weeks p. i. Control animals were sacrificed at once. The prostate- glands of the infected and control male hamsters were dissected; fixed in 10% phosphate buffered formalin. Microscopic examination was conducted on 4 microm thick H. and E. stained sections from paraffin embedded specimens. Immunohistochemical detection of hamster's schistosomal antigen in prostatic sections was performed by DAKO Avidin-biotin peroxidase technique. Other portions of the prostates were digested in 5% KOH for detection of S. mansoni eggs. The results of this work showed that there were diffuse, non granulomatous inflammatory reaction starting at 12[th] week p.i. and reaching maximum intensity at 16[th] week p.i. The epithelial linings of the prostatic acini showed hyperplasia, enfolding and lymphocytic cell infiltration. Stromal fibrosis started at 18[th] week p.i. in 10 [25%] infected hamsters. Immunohistochemical examination showed mild deposits at 12[th] week p.i., moderate deposits at 14[th] week p.i. and intense deposits at 16[th] week p.i. KOH digestion of prostatic pieces showed no S. mansoni ova at any period p. i. S. mansoni infection could involve the prostate gland by variable degrees of inflammation and fibrosis. These inflammatory reactions may be due to antigen deposition in such organ. The inflammation and fibrosis may interfere with the normal function of the prostatic gland leading to alteration of the chemical composition of the seminal fluid which may decrease the fertility capacity of the sperms. Also, prostatic hypertrophy may lead to problems in the erection and urinary tract obstruction