UCSF

Key PointsMemory lymphocytes have an indispensable role in eradicating pathogens. They mediate their effects by responding more robustly with repeated infections.Studies of immune memory have primarily focused on effector B cells and T cells. However, recent work has identified persistently expanded populations of antigen-specific regulatory T (TReg) cells.It is hypothesized that memory TReg cells are generated to regulate memory effector responses and to mitigate collateral damage to tissues in the face of these robust immune reactions.Memory TReg cells have been shown to have major roles in animal models of autoimmunity, antimicrobial host defence and maternal–fetal tolerance. In addition, there is evidence that these cells exist in humans.Lack of definitive markers has hampered the phenotypic and the functional characterization of memory TReg cells. Comprehensive transcriptional profiling and detailed examination of epigenetic and metabolic signatures will be essential in defining the functional role that memory TReg cells have in both health and disease.