Circulating KLRG1+ memory T cells retain the flexibility to become tissue-resident

KLRG1+ CD8 T cells persist for months after acute infections are cleared and maintain high levels of effector molecules, contributing essential protective immunity against systemic pathogens. Upon secondary infection, these long-lived effector cells (LLECs) are incapable of forming other circulating KLRG1− memory subsets such as central and effector memory T cells. Thus, KLRG1+ memory T cells are frequently referred to as a terminally differentiated population that is relatively short lived. Here, we show that during infection, effector cells derived from LLEC rapidly enter nonlymphoid tissues and reduce pathogen burden, but are largely dependent on receiving antigen cues from vascular endothelial cells. Single-cell RNA sequencing revealed that secondary memory cells in nonlymphoid tissues arising from either KLRG1+ or KLRG1− memory precursors developed a similar transcriptional signature. Thus, although KLRG1+ memory T cells cannot differentiate into other circulating memory population..., , , # Circulating KLRG1+ memory T cells retain the flexibility to become tissue-resident

[https://doi.org/10.5061/dryad.dncjsxm68](https://doi.org/10.5061/dryad.dncjsxm68)

The goal of this study was to determine if long-lived effector CD8 T cells (LLEC), which are usually confined to circulation will enter inflamed tissues upon infectious challenge and contribute to the resident memory T cell pool. This data set contains flow cytometry files (FCS files) and the raw tiffs from the microscopy files from each figure in the manuscript. The flow cytometry data was collected on isolated white blood cells isolated from various tissues. Briefly, purified populations of memory CD8 cell P14 or endogenous subsets were transferred into mice, and then the mice were infected with either LCMV or IAV-gp33. At differing time points tissues were harvested and processed for flow cytometry. Samples were stained with antibody cocktails that allowed for the identification of the transferred cells and the chara...