Dietary fiber promotes antigen presentation on intestinal epithelial cells and development of small intestinal CD4⁺CD8αα⁺ intraepithelial T cells.

ABSTRACT: The impact of dietary fiber on intestinal T cell development is poorly understood. Here we show that a low fiber diet reduces MHC-II antigen presentation by small intestinal epithelial cells (IECs) and consequently impairs development of CD4⁺CD8αα⁺ intraepithelial lymphocytes (DP IELs) through changes to the microbiota. Dietary fiber supports colonization by Segmented Filamentous Bacteria (SFB), which induces the secretion of IFNγ by type 1 innate lymphoid cells (ILC1s) that lead to MHC-II upregulation on IECs. IEC MHC-II expression caused either by SFB colonization or exogenous IFNγ administration induced differentiation of DP IELs. Finally, we show that a low fiber diet promotes overgrowth of Bifidobacterium pseudolongum, and that oral administration of B. pseudolon

SUBMITTER: Rodriguez-Marino N 

PROVIDER: S-EPMC11742265 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature