Figure 5: Sections of treated testes with rAT-MSCs. Most of the seminiferous tubules were empty indicating the absence of spermatogenesis. Only a few tubules appeared to be filled with spermatogenetic cells up (asterisks). Spermatogenetic cells were shown in these tubules (red arrow) (a2). Spermatozoa were also shown with arrows (orange arrows) (b1, b2, and c2). Sections of busulfan-treated testis (right), which are not transplanted with stem cells, demonstrate empty seminiferous tubules that indicate no spermatogenetic activity (d1, d2). The higher magnification of the slides (a1, b1, c1, and d1) was shown on the right of the same sections (a2, b2, c2, and d2). Original magnifications: a1, b1, d1-X48, c1, b2, d1-X100, a2, c2-X200.