Determinants of retroviral-mediated gene delivery to XXXX spermatogonia.

@entity19 @entity1 @entity1231 @entity899
Spermatogonia represent a new route to transgenesis in @entity19 and potentially in some commercially important domesticated animals. In addition, these cells are also a potential target for viral integration in @entity1 receiving somatic cell gene therapy. But the factors influencing retroviral transduction into spermatogonia are not well understood. Because retroviral transduction is affected in part by the proliferative status of the host cell, we developed an improved cell culture system in which spermatogonia survive and proliferate for several days. We used this system to test the ability of a variety of @entity19 and avian retroviruses to infect spermatogonia. We investigated the factors influencing retroviral transduction of spermatogonia, including the proliferative status of the infected cell, the type of viral envelope, the type of retroviral long terminal repeat, and the method of viral delivery. Here we show that many of the widely used retroviral vector systems can be used to successfully transduce spermatogonia at high efficiency. Moreover, we show that retroviral delivery of @entity1231 , the major downregulator of @entity899 , promotes spermatogonial survival in culture, suggesting that @entity899 plays a role in regulating spermatogonial apoptosis induced by growth factor deprivation. These results further demonstrate the usefulness of this novel system of targeting substances of interest to the testis. These data have important implications for improving animal transgenesis and for understanding the risks associated with somatic cell gene therapy.
