Confocal images of sections of the seminiferous tubules illustrated the existence of various iPS cell - derived EGFP - positive cells, including
flattened fibroblast cell - like myoid at the outermost layer of the tubules, spermatogonial stem cells with spherical nuclei closest to the basement membrane and spermatocytes with distinctive chromatin closer to the lumen than spermatogonial stem cells (Figure 6D).