Histopathology of the seminiferous tubules in mice injected with syngeneic testicular germ cells alone

Previously, a model of murine experimental autoimmune orchitis was produced by active immunization with viable syngeneic testicular germ cells without resorting to any adjuvants. The histological mode of the spermatogenic disturbance of this autoimmunity was investigated in A/J mice. A significant spermatogenic disturbance was consistently induced after the appearance of inflammatory cell responses around the tubuli recti. It first appeared seminiferous epithelium adjacent to the tubuli recti, then spread to the peripheral epithelium. The histopathology of the seminiferous tubules in the early phase ranged from partial degeneration and depletion of all kinds of germ cells to complete loss of germ cells other than some remaining spermatogonia, while both Sertoli cells and the basal lamina of the tubules appeared intact. In the late phase, depletion of Sertoli cells, disorganization of the seminiferous tubular wall or filling with many round-shaped degenerating germ cells, appearance of malformed spermatids with signet ring nuclei, depletion of immature germ cells with remaining elongated spermatids, or complete loss of the seminiferous epithelium were observed in addition to the early histopathological features.