Secondary infections rejuvenate the intestinal CD103+tissue-resident memory T cell pool

• DOI: 10.1126/sciimmunol.abp9553
• Publication Date: 2022-11-04T17:58:16Z
• Authors: Madlaina von Hoes...; Miriam Kuhlmann; Gustavo Pereira d...; Kristiyan Kanev; Christine Wurmser; Ann-Katrin Gerullis; Patrick Roelli; Jacqueline Berner; Dietmar Zehn
• Keywords: Inflammation; Mice; Memory T Cells; 0303 health sciences; 03 medical and health sciences; Coinfection; Reinfection; Animals; CD8-Positive T-Lymphocytes; Immunologic Memory

Resident T lymphocytes (T RM ) protect tissues during pathogen reexposure. Although phenotype and restricted migratory pattern are established, we have a limited understanding of their response kinetics, stability, turnover reinfections. Such characterizations been by the absence in vivo fate-mapping systems. We generated two mouse models, one to stably mark CD103 + cells (a marker cells) other specifically deplete − cells. Using these observed that intestinal became activated viral or bacterial reinfection, remained organ-confined, retained original but failed reexpand. Instead, population was largely rejuvenated formed de novo This unchanged upon deletion antigen-specific circulating cells, indicating lack expansion not due competition with subsets. Thus, although resident survived long term without antigen, they lacked ability classical memory indicated cell populations could autonomously maintain themselves. numbers were sustained reinfection via formation from precursors. Moreover, contrast - which require antigen plus inflammation for activation, fully follwing exposure alone. Together, our data indicate primary secondary potential precursors long-term maintenance.