Kurzfassung

In the first funding period our work mainly focused on in vitro spermatogenesis from pluripotent mouse stem cells, identification of putative markers for human spermatogonial stem cells (SSCs), and derivation of human SSCs. In the second funding period, we firstly plan to further improve the efficiency of in vitro spermatogenesis from mouse stem cells using different approaches like overexpression of stage-specific spermatogenesis genes. After successfully establishing a significantly...In the first funding period our work mainly focused on in vitro spermatogenesis from pluripotent mouse stem cells, identification of putative markers for human spermatogonial stem cells (SSCs), and derivation of human SSCs. In the second funding period, we firstly plan to further improve the efficiency of in vitro spermatogenesis from mouse stem cells using different approaches like overexpression of stage-specific spermatogenesis genes. After successfully establishing a significantly improved strategy in the mouse, we plan to transfer this strategy to human by deriving patient-specific induced pluripotent stem cells from infertile male individuals and using them for in vitro spermatogenesis. This will clarify, whether the infertility of the patients is due to exogenous or endogenous factors. Secondly, we will continue our efforts to reprogram human SSCs to pluripotency. Several genes representing new candidate markers for SSCs in vivo will be experimentally validated and used for enrichment of SSCs followed by reprogramming experiments using different methodologies. Thirdly, we plan to elucidate the role of germ cell-specific genes in transdifferentiation and pluripotency using extensive in vitro and in vivo studies which will be carried out on the genetic and epigenetic level. Fourthly, we will further analyze the SYCP3-DsRed transgenic mouse strain which was produced and characterized during the first funding period to study in detail different steps of spermatogenesis.» weiterlesen» einklappen