Multilayered structure of the basal lamina of the tubuli recti in normal mice.

Previous studies have demonstrated that the blood-testis barrier (BTB) at the tubuli recti (TR) and the rete testis (RT) is less complete than at the seminiferous tubules (ST). However, there has been no report focusing on the basal lamina, which is an important component of the BTB at both TR and RT. In the present study, we performed electron microscopic observation of the basal lamina at the TR and RT, in comparison with that of those of the ST in normal mice.

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.

Tissue microcircumstances for leukocytic infiltration into the testis and epididymis in mice.

Spermatozoa do not appear in the seminiferous epithelium until puberty, when immune tolerance has already been established. Therefore, they contain various autoimmunogenic materials which are recognized as foreign by the self immune system. However, the testis and epididymis are known as immunologically privileged organs.