Tregs, HSCT, and acute GVHD: up close and personal.

摘要

AlloHSCT provides curative graft-versus-tumor potential for patients with hematologic malignancies. However, donor effector immune responses to allogeneic (donor/recipient polymorphic) and autologous (donor/recipient nonpolymorphic) antigens also underlie acute and chronic graft-versus-host disease (GVHD), the major toxicities of this therapeutic approach. CD4~+CD25~+Foxp3~+ regulatory T lymphocytes comprise ~5% to 10% of circulating CD4~+ T cells and migrate to inflammatory sites to control innate and adaptive immune responses, especially those due to effector lymphocytes of helper T (Th) subsets: Th1, Th2, Thl7, and follicular Th cells (reviewed by Ohkura et al). Tregs play a critical role in the prevention of autoimmunity and several studies have suggested that Tregs also play a central role in the establishment and maintenance of immune tolerance after alloHSCT.