ARS | Publication request: Restoration of spermatogenesis after transplantation of c-Kit positive testicular cells in the fowl

Submitted to: Theriogenology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 13, 2010
Publication Date: December 20, 2010
Citation: Trefil, P., Bakst, M.R., Yan, H., Hejnar, J., Kalina, J., Mucksova, J. 2010. Restoration of spermatogenesis after transplantation of c-Kit positive testicular cells in the fowl. Theriogenology. 1670-1676.

Interpretive Summary: Transplanted testicular stem cells have been used for conventional breeding as well as for the production of transgenic offspring in mammals. In this study, we improved our previously published technique for the collection and transplantation of testicular cells between donor and recipient roosters. This was done by selecting and transplanting an enriched population testicular stem cells, the specific cells that give rise to sperm during spermatogenesis. Using a marker for c-Kit, a macromolecule only associated with testicular stem cells, we collected only c-Kit positive cells and transferred them into recipient sterilized males. These c-Kit positive testicular stem cells repopulated the testes of the sterilized recipient males and at the time of semen collection, about 9 wk after the transfer, donor male sperm were being produced by recipient males. When this semen was inseminated into hens, the hens produced progeny carrying donor genes from about 29 % of recipient males. The use of a select population of c-Kit positive cells to seed the recipient’s testes was more efficient in producing semen derived from the donor cells than in previous methods we published. We plan to use this approach to make transgenic poultry by inserting gene constructs into the c-Kit positive cells before transfer to the recipients.

Technical Abstract: Transplantation of male germ line cells into sterilized recipients has been used in mammals for conventional breeding as well as for transgenesis. This study presents an improvement in the approach for germ cell transplantation between fowl males by using an enriched subpopulation of c-Kit positive spermatogonia as donor cells. Dispersed c-Kit positive testicular cells, from 16 to 17 weeks old pre-pubertal donors were transplanted by injection directly into the testes of recipient males sterilized by repeated gamma irradiation. We describe the re-population of the recipient’s testes with c-Kit positive donor testicular cells up to the production of a population of heterologous spermatozoa. Using manual semen collection, the first ejaculates of the recipient males following were observed about nine weeks after the transfer of c-Kit positive testicular cells. Following insemination of the recipients semen, hens produced progeny carrying donor genes from about 29 % of recipient males. Time course of the weekly sperm output in two recipient chicken males transplanted with dispersed c-Kit positive testicular cells in comparison of the polynomial regression equations revealed significant differences (p < 0.05) in the number of ejaculated spermatozoa produced after transplantation.