RNAseq of colonic epithelial and lamina propria-derived Tregs

Local tissue adaptation by immune cells is of especially high importance in the small and large intestines, the largest mucosal barrier surface in the body. Recent work on tissue resident T cells has focused on CD8+ “tissue resident memory cells” or Trm. However, the human colon also contains different populations of CD4+ T cells, in mice referred to as “intraepithelial lymphocytes” and “lamina propria lymphocytes”. Our results uncover a pattern of compartmentalized tissue adaptation of human colonic CD4+ T cells in the steady state. This pattern is lost during active Inflammatory Bowel Disease, with potential detrimental effects on barrier maintenance and continued inflammation.