A new model for antisperm autoimmunity in guine pigs.

Adult outbread male guinea pigs were autoimmunized without adjuvant. Homogenates were prepared with one of their own testes previously submitted "in vivo" and "in vitro" to thermal injury. Animals received a single or daily repeated intradermal injection without added adjuvant, in one or different skin sites. Guinea pigs daily sensitized in the same site during 30 days showed the presence of: a) dermal granuloma at the site of injection; b) several foci of typical allergic orchitis; c) delayed hypersensitivity detected by inhibition of macrophage migration; d) moderate titres of spermagglutinins and negligible levels of hemagglutinating antibodies. Guinea pigs receiving a single dose in one site only developed delayed hypersensitivity. Animals daily sensitized with the same dose of altered antigen in different sites, or with normal testis antigen either in one or different sites, showed negative results. The correlation among testicular lesion, dermal granuloma and cellular immunity is discussed. It is concluded that testis autosensitization is obtained in the absence of added adjuvant provided that a thermally injured gonad used as antigen is repeatedly injected in the same site.