Figure 1.

Light microscopy of the macaque testis and epididymis (PAS staining). A. Testis of an immature monkey: only seminiferous cords containing Sertoli cells and basally situated spermatogonia (long arrow) are present. B. Epididymis of immature monkey: note absence of germ cells in the epididymal lumen (block arrow). C. Spermatogenesis occuring in the testis of a more mature monkey (block arrow indicates elongated spermatids). D. Sperm present in the epididymal lumen of a mature monkey (block arrow). E. Epididymides of some infected monkeys were characterized by the presence of large mononuclear cell infiltrates (arrows). Macrophages are present in the testicular and epididymal tissues (short arrows, panels A – D). Indicated macrophages and T cells are also shown in higher magnifications (panels A, D and E).