Immunomorphological aspects of the tubuli recti and the surrounding interstitium in normal mice.

The tubuli recti (TR) are immunologically special, because the lymphocytes preferably accumulate around them during the course of T-cell dependent testicular autoimmunity in mice. This finding implies that the testicular interstitium around the TR is where autoreactive lymphocytes can gain access to autoimmunogenic germ cell antigens. In the present study, the histoarchitecture of the TR was minutely examined in normal mice. Three-dimensional analysis showed that 14-16 TR appeared to be connected to the rete testis (RT). Electron microscopical analysis revealed that the epithelial cells in the TR formed protruding cytoplasmic strings, with active endocytosis of degenerated spermatozoa, and exhibited three different morphological characteristics. Furthermore, a few macrophages were found to have penetrated into the TR. Immunohistochemical image analysis revealed that more macrophages specifically accumulated around the TR than the RT or seminiferous tubules. These findings indicate that macrophages preferentially accumulate around the TR, where contact between germ cell antigens and macrophages may occur under normal and pathological conditions.

Di-(2-ethylhexyl) phthalate induces severe aspermatogenesis in mice, however, subsequent antioxidant vitamins supplementation accelerates regeneration of the seminiferous epithelium.

Di-(2-ethylhexyl) phthalate (DEHP), now regarded as an endocrine disruptor, can experimentally induce spermatogenic disturbance in laboratory animals. Our previous study demonstrated that antioxidant vitamins (vitamins C and E) supplementation during DEHP-treatment significantly protected the rat seminiferous epithelium from DEHP-gonadotoxicity. In the present study, we gave these antioxidant vitamins to mice already having fully developed aspermatogenesis because of DEHP to determine whether or not the vitamins can cure the injured seminiferous epithelium. CD-1 male mice were fed on a DEHP-containing diet for 15 days and then fed on the DEHP-free normal diet with or without supplementation of vitamins C and E in drinking water for another 50 days. The results showed that severe aspermatogenesis was induced by the DEHP-treatment but that the damaged seminiferous epithelium spontaneously recovered whether the vitamins were provided or not. This indicates that the DEHP-induced aspermatogenesis was reversible. However, the supplementation of antioxidant vitamins significantly accelerated regeneration of the injured seminiferous epithelium, suggesting that the vitamins have a therapeutic effect on DEHP-induced aspermatogenesis.

Proinflammatory effects of exogenously administered IL-10 in experimental autoimmune orchitis.

We studied the effects of exogenously administered recombinant murine interleukin (IL)-10 on the development of experimental autoimmune orchitis (EAO) in C3H/He mice. IL-10 significantly augments histological signs of EAO when administered for 6 consecutive days from days 15 to 20 after primary immunisations with testicular germ cells. These data demonstrate that IL-10, in addition to its well-known antiinflammatory property, also has proinflammatory functions capable of up-regulating testicular immunoinflammatory processes in vivo.