Multifocal damage of the testis induced in rats by passive transfer of antibodies prepared against non-collagenous fraction of basement membrane

Abstract

Multifocal damage of the testis was induced in 70% of the rats injected with an antiserum against a non-collagenous fraction (D-STBM) obtained from a preparation enriched in basement membranes of seminiferous tubules. The damaged areas were characterized by perivascular and peritubular cell infiltrates, changes in the walls of small vessels and seminiferous tubules, and sloughing of the germinal epithelium. By electron microscopy, the most frequent changes observed in basement membrane of the seminiferous tubules were folding, focal thickening, and delamination. By immunofluorescence, discontinuous linear deposits of rabbit IgG were observed along the walls of the seminiferous tubules. In the same localization, faint immunofluorescence showing the presence of rat IgG was also detected. The same pattern was obtained when rabbit and rat IgG eluted from the testes of these rats were layered on sections of normal rat testis. Moreover, by immunoelectron microscopy, discontinuous deposits of rabbit IgG were detected along the basement membranes of the seminiferous tubules. Neither C3 deposits nor changes in the serum CH 50 were observed. By leucocyte migration inhibition reaction (LMIR) a cellular immune response to basement membrane antigens was detected. In the control group, 12% of the rats injected with normal rabbit serum presented mild interstitial cell infiltrates and occasional sloughing of the germinal epithelium. Neither deposits of rat IgG or rabbit IgG nor a cellular immune response were observed.