New insights on T-cell self-tolerance

Self-tolerance of T cells is maintained by a combination of thymic negative selection and suppression by T regulatory cells (Tregs); both processes are driven by recognition of self MHC ligands. Treg function ensures that most T cells remain quiescent as naive cells, but enables some T cells to proliferate and differentiate into cells with a memory phenotype (MP). In this review, we discuss how Tregs shape this compartmentalization of T cells into subsets of naive and MP T cells.