Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N4N1, Canada.
Recombinetics, Inc., St. Paul, MN 55121, USA.
Cells. 2023 Nov 6;12(21):2582. doi: 10.3390/cells12212582.
Spermatogonial stem cell (SSC) transplantation into the testis of a germ cell (GC)-depleted surrogate allows transmission of donor genotype via donor-derived sperm produced by the recipient. Transplantation of gene-edited SSCs provides an approach to propagate gene-edited large animal models. DAZL is a conserved RNA-binding protein important for GC development, and knockout (KO) causes defects in GC commitment and differentiation. We characterized -KO pigs as SSC transplantation recipients. While there were GCs in 1-week-old (wko) KO, complete GC depletion was observed by 10 wko. Donor GCs were transplanted into 18 -KO recipients at 10-13 wko. At sexual maturity, semen and testes were evaluated for transplantation efficiency and spermatogenesis. Approximately 22% of recipient seminiferous tubules contained GCs, including elongated spermatids and proliferating spermatogonia. The ejaculate of 89% of recipients contained sperm, exclusively from donor origin. However, sperm concentration was lower than the wild-type range. Testicular protein expression and serum hormonal levels were comparable between -KO and wild-type. Intratesticular testosterone and Leydig cell volume were increased, and Leydig cell number decreased in transplanted -KO testis compared to wild-type. In summary, -KO pigs support donor-derived spermatogenesis following SSC transplantation, but low spermatogenic efficiency currently limits their use for the production of offspring.
精原干细胞 (SSC) 移植到耗尽生殖细胞 (GC) 的受体睾丸中，可通过受体产生的供体来源精子传递供体基因型。编辑后的 SSC 移植为繁殖编辑后的大型动物模型提供了一种方法。DAZL 是一种对 GC 发育很重要的保守 RNA 结合蛋白，而 KO 会导致 GC 承诺和分化缺陷。我们将 -KO 猪作为 SSC 移植受体进行了特征描述。虽然在 1 周龄（wko）的 KO 中有 GC，但在 10 周龄时已经观察到 GC 完全耗尽。在 10-13 周龄时，将供体 GC 移植到 18 只 -KO 受体中。在性成熟时，对精液和睾丸进行评估以确定移植效率和精子发生情况。大约 22%的受体生精小管含有 GC，包括伸长的精子细胞和增殖的精原细胞。89%的受体的精液中含有精子，这些精子完全来自供体。然而，精子浓度低于野生型范围。-KO 和野生型之间睾丸蛋白表达和血清激素水平相当。与野生型相比，移植的 -KO 睾丸内的睾丸内睾酮和间质细胞体积增加，而间质细胞数量减少。总之，-KO 猪在 SSC 移植后支持供体来源的精子发生，但目前低的精子发生效率限制了它们用于生产后代。
