Intraspecific Transplantation Of Spermatogonial Stem Cells With Transgene

[BACKGROUND & AIM] The spermatogonial stem cell is the foundation of spermatogenesis and it continues to divide throughout the lifetime of a male. It divides to renew itself as well as to produce daughter cells that finally differentiate to spermatozoa. Spermatogonial stem cell transplantation (SSCT) means that donor testis cells can be transplanted to recipient testes where they re-establish spermatogenesis. SSCT was first reported by Ralph Brinster's laboratory in 1994. It has proven to be a technological breakthrough in the study of both stem cells and Sertoli cell-germ cell interactions. This transfer technique, combined with developments in cryopreservation, long-term culture, and the enrichment of stem cell populations makes more significant breakthroughs likely in the near future. It provides a broad avenue for academic research and practical application in basic science, human medicine, and domestic and wild animal reproduction. SSCT has numerous potential applications: ①SSCs were transplanted from a fertile male into the seminiferous tubules of infertile male to restore fertility, which results in the development of donor cell derived spermatogenesis. ②Men or boys who receive chemotherapy or radiation treatments for cancer have the options to safeguard their fertility. ③SSCs will become a promising and feasible approach to prevent those lethal or life-threatening diseases caused by inborn errors and to perform germline gene therapy. ④It is a powerful technique to study on spermatogenesis.⑤It is very useful for preserving the germ line of valuable animals.In this study, Red-fluorescent protein (DsRed2) genes were mediated by Dosper lipidsome to spermatogonial stem cells of donor mice in vitro and in vivo respectively. The DsRed2 gene-transfected cells after isolating and purifying were transplanted into the seminiferous tubules of anesthetized recipients depleted of germ cells by busulfan treatment. The testes and epididymis of recipients at 6 weeks and 10 weeks after transplantation were excised and the frozen-cut sections were prepared and analyzed under fluorescence microscope and light microscope, respectively to explore the behavior of donor spermatogonial stem cells with exogenous gene in recipient testes after transplantation.