T regulatory cell therapy in preclinical and clinical pancreatic islet transplantation

Cell therapy with regulatory T cells (Tregs) is a promising immunomodulatory approach to promote transplant tolerance in patients with type 1 diabetes (T1D) undergoing pancreatic islet transplantation. While several clinical trials with Tregs are ongoing in the clinical setting of hematopoietic stem cell transplantation (HSCT), T1D, renal and kidney transplantation, only one Treg immunotherapy phase I clinical trial is currently active in the setting of allogeneic pancreatic islet transplantation. In this chapter, we summarize available preclinical Treg cell therapy data conducted in the setting of experimental pancreatic islet transplantation and discuss potential challenges, for example, compatibility with immunosuppression, safety and efficacy for Treg cell therapies not yet in the clinic. We also summarize available clinical data from Treg cell therapies conducted in the liver, kidney transplantation, and T1D.