Regulatory T cells for tolerance.

Regulatory T cells (Tregs) are critical mediators of immune homeostasis and hold significant promise in the quest for transplantation tolerance. Progress has now reached a critical threshold as techniques for production of clinical therapies are optimised and Phase I/II clinical trials are in full swing. Initial safety and efficacy data are being reported, with trials assessing a number of different strategies for the introduction of Treg therapy. It is now more crucial than ever to elucidate further the function and behaviour of Tregsin vivoand ensure safe delivery. This review will discuss the current state of the art and future directions in Treg therapy.