Formation and Maintenance of Tissue Resident Memory CD8+ T Cells after Viral Infection

Tissue resident memory (T(RM)) CD8 T cells comprise a memory population that forms in peripheral, non-lymphoid tissues after an infection that does not recirculate into the bloodstream or other tissues. T(RM) cells often recognize conserved peptide epitopes shared among different strains of a pathogen and so offer a protective role upon secondary encounter with the same or related pathogens. Several recent studies have begun to shed light on the intrinsic and extrinsic factors regulating T(RM). In addition, work is being done to understand how canonical “markers” of T(RM) actually affect the function of these cells. Many of these markers regulate the generation or persistence of these T(RM) cells, an important point of study due to the differences in persistence of T(RM) between tissues, which may impact future vaccine development to cater towards these important differences. In this review, we will discuss recent advances in T(RM) biology that may lead to strategies designed to promote this important protective immune subset.