TCR tuning of T cell subsets

Summary After selection in the thymus, the post‐thymic T cell compartments comprise heterogenous subsets of naive and memory T cells that make continuous T cell receptor ( TCR ) contact with self‐ligands bound to major histocompatibility complex ( MHC ) molecules. T cell recognition of self‐ MHC ligands elicits covert TCR signaling and is particularly important for controlling survival of naive T cells. Such tonic TCR signaling is tightly controlled and maintains the cells in a quiescent state to avoid autoimmunity. Here, we review how naive and memory T cells are differentially tuned and wired for TCR sensitivity to self and foreign ligands.