Germ cell transplantation and the study of testicular function.

Spermatogonial stem cell transplantation is a novel technique in which donor testicular cells are transferred into recipient testes. A population of germ cells from a transgenic or mutant donor is introduced into the seminiferous tubules of recipient testes by microinjection. Following injections, spermatogonial stem cells can colonize the recipient testis, initiate spermatogenesis and produce sperm capable of fertilization. This technique will allow scientists to: (1) investigate fundamental aspects of spermatogenesis; (2) provide a method to regenerate spermatogenesis in infertile individuals; and (3) genetically manipulate spermatogonial stem cells to develop transgenic animals.