Immortalization of primary baby rat kidney cells by retroviral mediated gene transfer of adenovirus E1A genes.

We describe a retroviral mediated gene transfer system that facilitates the transfer of heterologous genes into primary epithelial cells. Using a series of retroviral vectors containing the genes coding for the 12S and 13S mRNAs from the E1A region of adenovirus type 5 and the hygromycin resistance gene as a selectable marker, we demonstrate that, when packaged as helper virus-free amphotropic particles, these recombinant retroviruses infect murine fibroblasts and rat and human epithelial cells. Moreover, one of these constructs, containing genes for either the 12S or 13S product, is able to immortalize primary baby rat kidney epithelial cells in vitro and, thus, when used in combination with optimized culture conditions, may facilitate the establishment in culture of primary epithelial cells from a wide variety of tissues and species.