Regulatory T-cell immunotherapy for tolerance to self antigens and alloantigens in humans

Substantial progress in understanding the biology of regulatory T cells andtheir roles in health and disease has been achieved in the past 10 years. This has led toan increasing interest in the possibility of using regulatory T cells as a biological therapyto preserve and restore tolerance to self antigens and alloantigens. Immunotherapy bythe adoptive transfer of regulatory T cells may have several advantages over conventionaltreatments. However, several hurdles have to be overcome before such a therapy can enterclinical practice. This Review summarizes our current knowledge of regulatory T cells,illustrates the ongoing regulatory T-cell-based clinical trials, analyses the strengths andpitfalls of this new therapeutic approach, and highlights the future perspectives.