Generation of male germ cells in vitro from the stem cells

Infertility has become a serious disease since it affects 10%-15% of couples worldwide, and male infertility contributes to about 50% of the cases. Notably, a significant decrease occurs in the newborn population by 7.82 million in 2020 compared to 2016 in China. As such, it is essential to explore the effective methods of obtaining functional male gametes for restoring male fertility. Stem cells, including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), spermatogonial stem cells (SSCs), and mesenchymal stem cells (MSCs), possess the abilities of both self-renewal and differentiation into germ cells. Significantly, much progress has recently been achieved in the generation of male germ cells in vitro from various kinds of stem cells under the specified conditions, e.g., the coculturing with Sertoli cells, three-dimensional culture system, the addition of growth factors and cytokines, and/or the overexpression of germ cell-related genes. In this review, we address the current advance in the derivation of male germ cells in vitro from stem cells based on the studies of the peers and us, and we highlight the perspectives and potential application of stem cell-derived male gametes in reproductive medicine.

Automated summary

Infertility affects 10%-15% of couples worldwide, with male infertility accounting for 50% of the cases. In China, there has been a significant decrease in the newborn population by 7.82 million in 2020 compared to 2016. Stem cells, including ESCs, iPSCs, SSCs, and MSCs, have the potential to differentiate into male germ cells, and recent progress has been made in generating male germ cells in vitro from stem cells under specific conditions. This review addresses the current advancements in deriving male germ cells from stem cells and discusses their potential applications in reproductive medicine.