Development of a flexible and specific gene delivery system for productionof murine tumor models

To develop models of human cancer ne have expressed the avian retroviral re ceptor, TVA, under a variety of mammalian promoters in transgenic mice, thu s rendering mice susceptible to infection with avian leukosis virus-derived gene vectors. TVA-based retroviral gene transfer offers advantages ol er c urrent murine models of human cancer. A single transgenic mouse line can be used to evaluate multiple genetic lesions, individually and in combination . Furthermore, mutant genes are introduced somatically into animals, as occ urs in the majority of naturally occurring turners. Because the avian viral vectors replicate only in avian cells, the viral receptor in infected tran sgenic mouse cells remains available for multiple rounds of infection with different ASLV vectors. We discuss the theoretical and practical aspects of using recombinant avian retroviruses with TVA transgenic mice to generate cancer models.