Spermatogonial stem cells (SSCs) provide the foundation for spermatogenesis. During the last decade, several techniques forthe manipulation of this cell type have been developed; as a result, SSCs can now be subjected to long-term in vitro expan-sion and genetically manipulated for knockout mouse production. These techniques have allowed SSCs to serve as a new tar-get for animal transgenesis, which may provide an alternative to embryonic stem (ES) cells. Furthermore, SSCs may beconverted into ES-like cells, demonstrating that the postnatal testis is a source of pluripotent stem cells. These techniques werefirst established in mice, but they are currently being extended to other animal species. SSC-based technologies will be use-ful in agriculture and medicine and will also provide valuable opportunities to study SSC biology. The mechanisms of self-renewal division and differentiation and the regulation of pluripotency in SSCs are now being studied at the molecular level.However, some technical and conceptual pitfalls must be kept in mind when designing and analyzing experimental results.Nevertheless, these advances in SSC research will provide valuable insight into the study of mammalian stem cell systems.
展开▼
