Researchers at Vanderbilt have created a novel drug delivery system using two distinct T-cell populations that interact to promote engraftment and persistence in pre-clinical models, increasing the efficacy of T-cell therapies. Furthermore, "booster" treatments can be administered months after the first dose to produce an expansion of antigen specific T cells. These advantages result in longer-term therapeutic efficacy and could reduce the number of treatments required. This system also represents a viable self-renewing platform for the delivery of biologic drugs in patients who would otherwise require frequent administration.