%0 Journal Article
%T Lymphatic vessel transit seeds cytotoxic resident memory T cells in skin draining lymph nodes.
%A Heim TA
%A Schultz AC
%A Delclaux I
%A Cristaldi V
%A Churchill MJ
%A Ventre KS
%A Lund AW
%J Sci Immunol
%V 9
%N 96
%D 2024 Jun 7
%M 38848340
%F 30.63
%R 10.1126/sciimmunol.adk8141
%X Lymphatic transport shapes the homeostatic immune repertoire of lymph nodes (LNs). LN-resident memory T cells (TRMs) play an important role in site-specific immune memory, yet how LN TRMs form de novo after viral infection remains unclear. Here, we tracked the anatomical distribution of antiviral CD8+ T cells as they seeded skin and LN TRMs using a model of vaccinia virus-induced skin infection. LN TRMs localized to the draining LNs (dLNs) of infected skin, and their formation depended on the lymphatic egress of effector CD8+ T cells from the skin, already poised for residence. Effector CD8+ T cell transit through skin was required to populate LN TRMs in dLNs, a process reinforced by antigen encounter in skin. Furthermore, LN TRMs were protective against viral rechallenge in the absence of circulating memory T cells. These data suggest that a subset of tissue-infiltrating CD8+ T cells egress from tissues during viral clearance and establish a layer of regional protection in the dLN basin.