Embryonic stem cell-like cells derived from adult human testis

Abstract

Multipotent cells can be established from adult human testis. Their easy accessibility and ethical acceptability as well as their non-tumorigenic and autogenic nature make these cells an attractive alternative to human ES cells for future stem cell therapies.

Spermatogonial stem cells: Current biotechnological advances in reproduction and regenerative medicine

“…Although one work demonstrated teratoma formation and pluripotency markers expression [66] on these cells, tumors showed a relatively small volume [67] . Several other groups have produced allegedly human mGS cells as well, but these cells, although expressing several pluripotency markers, do not produce teratomas when transplanted into the skin of immunocompromised mice [68][69][70] . In fact, one group recently found that human testicular embryonic-like cells (allegedly mGS pluripotent cells) do not possess a transcriptome similar to that of human ES cells but rather have the phenotype of mesenchymal stem cells (MSCs), therefore, concluding that these cells are not pluripotent and most likely not of germ cell origin but instead mesenchymal [71] .…”

Alteration in genes expression patterns during in vitro differentiation of mouse spermatogonial cells into neuroepithelial-like cells

“…Spermatogonia cells may represent a possible alternative to embryonic stem cells for cell therapy in replacing of neurons and glia (Mizrak et al 2010).…”

Potential applications of germline cell-derived pluripotent stem cells in organ regeneration

“…They could be cryopreserved and thawed with no loss in proliferation or differentiation capacity. 17,30,31 However, there is discrepancy between the reports of Conrad et al and Kossack et al, mainly due to the SSC isolation methods employed. 17,30 The former used a three-step procedure to isolate integrin α6 + SSCs from human testicular parenchymas and derived pluripotent ES-like cells (22 out of 22 patients) while the latter cultured testicular cells from testis biopsies using human ES media with subsequent transfer onto mouse embryonic fibroblasts and derived ES-like cells (1 patient) that differed from human ES cells in gene expression, methylation and ability to form teratomas and which were thus considered multipotent.…”

“…32 Mizrak et al obtained multipotent hGPSCs, which did not form extensive teratomas upon injection into immunocompromized mice. 31 Improved and standardized SSC isolation and culture methods need to be established to clarify this issue of pluripotency/multipotency of hGPSCs. Moreover, the identity of the human germ cells, collectively termed spermatogonia or SSCs, that convert to ES-like cells should be better characterized.…”