Abstract
There is a clear need to develop strategies to induce tolerance without the need of chronic immunosuppression in transplant recipient and in patients with autoimmunity. Adoptive T regulatory cell (T(reg)) therapy offers the potential of long-lasting protection. However, based on results of clinical trials so far with ex vivo expanded autologous T(regs) in type 1 diabetic (T1D) patients, it seems unlikely that single immunotherapy with T(reg) infusion without immunomodulation regimens that promote stable donor T(reg) engraftment and persistence would afford truly significant clinical benefit. Combination therapies could provide improved outcomes with consideration of the fundamental factors required for T(reg) generation, homeostasis, and function to promote long-term donor T(reg) persistence to provoke beneficial therapeutic outcomes.