BACKGROUND: Gene transfer studies in primary T cells have suffered from the limitations of conventional viral transduction or transfection techniques. Replication-defective adenoviral vectors are an attractive alternative for gene delivery. However, naive lymphocytes are not readily susceptible to infection with adenoviruses due to insufficient expression of the coxsackie/adenovirus receptor. RESULTS: To render T cells susceptible to adenoviral gene transfer, we have developed three new murine transgenic lines in which expression of the human coxsackie/adenovirus receptor (hCAR) with a truncated cytoplasmic domain (hCAR(Delta)cyt) is limited to thymocytes and lymphocytes under direction of a human CD2 mini-gene. hCAR(Delta)cyt.CD2 transgenic mice were crossed with DO11.10 T cell receptor transgenic mice (DO11.hCAR(Delta)cyt) to allow developmental studies in a defined, clonal T cell population. Expression of hCAR(Delta)cyt enabled adenoviral transduction of resting primary CD4+ T cells, differentiated effector T cells and thymocytes from DO11.hCAR(Delta)cyt with high efficiency. Expression of hCAR(Delta)cyt transgene did not perturb T cell development in these mice and adenoviral transduction of DO11.hCAR(Delta)cyt T cells did not alter their activation status, functional responses or differentiative potential. Adoptive transfer of the transduced T cells into normal recipients did not modify their physiologic localization. CONCLUSION: The DO11.hCAR(Delta)cyt transgenic model thus allows efficient gene transfer in primary T cell populations and will be valuable for novel studies of T cell activation and differentiation.