Establishment of adult mouse testis-derived multipotent germ line stem cells and comparison of lineage-specific differentiation potential

Primordial germ cells (PGCs) as well as fetal germ line stem cells (GSCs) are pluripotent cells. Their differentiation potential is similar to that of embryonic stem cells (ESCs), suggesting that germ line lineage may retain the potential to form pluripotent cells. Here we report successful establishment of multipotent germ line stem cells (mGSCs) from cells obtained from adult mouse testis. We obtained testes from Pou5f1 (Oct4)-GFP transgenic mice and demonstrate that the germ cells present in testes can be converted to pluripotent stem cell-like cells. The newly established mGSCs had similar morphology and growth characteristics as that of ESCs and expressed markers of pluripotency. To assess the differentiation potential of mGSCs in vivo and in vitro, we performed a teratoma formation assay and in vitro differentiation via embryoid body (EB) formation. Multipotent GSC-derived teratomas contained derivatives of all the three embryonic germ layers and differentiated into multiple lineages in vitro, including cardiomyocytes and neural cells. Using real-time qPCR analysis, we compared the gene expression pattern in the newly established mGSCs with those of pluripotent stem cells, germ cells, and testicular cells. The differentiation potential of the newly established mGSCs was comparable to that of ESCs and induced pluripotent stem cells (iPSCs). Multipotent GSCs derived from adult testes can be used for personalized cell-based therapies without the ethical and immunological problems.