The development of immunosuppressant treatments has enabled remarkable progress in the tissue and organ transplantation field by helping to prevent acute graft rejection. However, complications related to transplantation, such as infection by bacteria and viruses, and the occurrence of cancers resulting from prolonged immune suppression are major obstacles to overcome. Therefore, transplantation immunology research efforts should focus on the induction of donor-specific immune tolerance which preserves patient immune competence which promotes infection and cancer surveillance. Additionally, lifelong administration of immunosuppressants should be forgone in preference to short term therapies. In the 1990s, Dr. Shimon Sakaguchi identified the CD4⁺CD25⁺ regulatory T cells which develop in the thymus, and demonstrated that these cells play crucial roles in the maintenance of immune self tolerance. Studies which followed proved that these regulatory T cells are important to the control of autoimmune disease and prevention of graft rejection. Regulatory T cells have also been found to induce immune tolerance in rodent models. In this review, we discuss several considerations for the use of regulatory T cell therapy in the clinical transplantation field.

Keywords: Transplantation, Immune tolerance, Regulatory T lymphocytes