Restoration of Spermatogenesis and Male Fertility by Transplantation of Dispersed Testicular Cells in the Chicken1

Abstract

Transplantation of male germ cells into sterilized recipients has been widely used in mammals for conventional breeding and transgenesis purposes. This study presents a workable approach for germ cell transplantation between male chickens. Testicular cells from adult and prepubertal donors were dispersed and transplanted by injection directly into the testes of recipient males sterilized by repeated gamma irradiation. We describe the repopulation of the recipient seminiferous epithelium up to the production of heterologous sperm in about 50% of transplanted males. In comparison to males transplanted with testicular cell preparations from adult donors, in which the first ejaculates with sperm were recovered about 5 wk after transfer, a substantial interval (about 10 wk) was necessary to obtain ejaculates after the transfer of testicular cells from prepubertal donors. However, in both cases, recipient males produced ejaculates capable of fertilizing ova and producing progeny expressing donor genes.

Retrovirus-mediated in vitro gene transfer into chicken male germ line cells

“…This efficiency is comparable with animals transplanted in parallel directly with uninfected testicular cells, but a bit lower in comparison with our previous transplantation experiments (Trefil et al 2006), where the efficiency reached 50%. Small numbers of birds used in these experiments might cause such differences.…”

“…Trefil et al (2006) have shown previously that this transplantation in chickens resulted in the re-colonization of the seminiferous epithelium with partial resumption of spermatogenesis and production of viable and fertilization-competent spermatozoa. In this report, we have continued our studies and observed the functional recovery of exogenous spermatogenesis after transplantation of in vitro infected testicular cell mixture.…”

“…Inbred Black Minor (BM; genotype ii, EE, b/b) and White Leghorn (WL; genotype II) cockerels at the age of 32 weeks were used as donors and recipients of testicular cells respectively, as successful transplantation of testicular cells from BM into WL cockerels was demonstrated previously in our chicken germ cell transplantation model (Trefil et al 2003(Trefil et al , 2006. Three males of the same genetic origin as recipients were retained as positive controls and other three males were subjected to the same sterilizing treatment as recipient males but kept untransplanted as negative controls.…”

“…In contrast, avian spermatogenesis is poorly understood (Thurston & Korn 2000) and SSCs as well as other germ cells of the seminiferous epithelium have yet to be well characterized in birds. Recently, we have demonstrated that the transfer of dispersed testicular cells from fertile donor cockerels resulted in the colonization of infertile recipient testes with final production of viable and fertilization-competent spermatozoa (Trefil et al 2006). Therefore, efficient gene delivery into the crude mix of testicular cells may target the rare SSCs and pave the way to chicken transgenesis.…”

Spermatogonial Stem Cells and Animal Transgenesis

“…Although most studies have been performed in rodents, germ cell transplantation has also been applied to non-rodent species as pigs, goats, cattle, monkeys and recently fish and chickens (Honaramooz et al, 2002a(Honaramooz et al, ,b, 2003Schlatt et al, 2002;Izadyar et al, 2003b;Takeuchi et al, 2003;Yoshizaki et al, 2005;Lee et al, 2006;Mikkola et al, 2006;Okutsu et al 2006;Trefil et al 2006), as reviewed by Dobrinski, (2008). The first hurdle found when germ cell transplantation was applied to livestock species was the differences in testicular anatomy and physiology.…”