ADENOVIRUS-MEDIATED GENE-TRANSFER TO RAT TESTIS IN-VIVO

To study transgene expression in the adult rat testis in vivo, an aden ovirus vector carrying a lacZ transgene with a nuclear localization si gnal was used as a marker. The adenovirus vector was first tested on r at Sertoli cell-germ cell cocultures in vitro; it efficiently mediated transgene expression in Sertoli cells but not germ cells. This vector was then delivered to the interstitial compartment of adult rat teste s by intratesticular injection, resulting in Leydig cells expressing t he transgene. Alternatively, delivering the vector to the intratubular compartment by rete testis injection resulted in expression of the tr ansgene by Sertoli cells of the seminiferous epithelium and principal cells of the epididymis. In vivo, each cell type expressed the transge ne by 2 days postinfection, and expression persisted for at least 10 d ays; however, later time points were associated with a loss of transge ne expression and focal interstitial inflammation. This study document s the ability of adenovirus to mediate gene transfer to specific testi cular cells, providing a powerful tool to study the short-term effects of specific genes on spermatogenesis in vivo.