UC San Diego

CD8+ tissue-resident memory T cells play a well-established role in host defense againstmicrobial pathogens but have also been recently implicated in playing a role in the pathogenesis of inflammatory and autoimmune diseases. Previous work demonstrated that the T-box transcription factor Eomes is extinguished during the formation of skin TRM cells owing to TGF- ꞵ signaling. However, our lab previously observed high expression of Eomes in a pathogenic CD8+ TRM subset enriched in patients with ulcerative colitis, a form of inflammatory bowel disease. Thus, we sought to investigate the role of Eomes in the maintenance of TRM in small intestine and colon tissue compartments. We adoptively transferred congenically distinct wildtype and Eomesfl/fl ER-Cre+ CD8+ P14 cells into recipient mice and infected them with LCMV. We administered tamoxifen injections to inducibly delete Eomes at 30 days post-infection after the formation of TRM cells. Our results suggest that Eomes plays a previously unappreciated function in intestinal TRM maintenance through a potential role in regulating tissue damage and TGF-ꞵ responsiveness.