Figure 6: The SSEA-4 positive cells of human testis maintain their SSC identity in long-term culture. qRT-PCR analysis of the expression of the pluripotency and hESC marker genes (SSEA-4, POU5F1, cMYC, SOX2, KLF4, NANOG, LIN28), the SSC marker genes (GPR125, PLZF) and spermatogonial marker gene ITGA6. The bars represent the relative levels of expression of the corresponding genes in the following cell populations: SSEA-4(+) cells freshly isolated from human testis with MACS, SSEA-4(+) cells that have been cultured for 1 month in SSC-maintenance media (short-term culture), SSEA-4(+) cells that have been cultured for 5 months in SSC-maintenance media (long-term culture) and induced pluripotent stem cells (iPSCs), used as control. The different samples were assayed in triplicates and normalized to GAPDH.