Tfam-Mediated Metabolic Perturbation in RORgt+ Lymphocytes Impacts Intestinal Tissue Homeostasis and Promotes GATA3+RORgt+ Innate Lymphoid Cells
Rorc-mediated deletion of Tfam, a mitochondrial transcription factor, causes tuft cell-type 2 immunity-driven small intestine (SI) lengthening in mice. Here, we report an indispensable role for Th2 cells in this process. High-fat diet (HFD) reverts SI lengthening in Tfamf/fRorc-cre mice by suppressing IL-13-producing Th2 cells and IL-17-producing Th2 and ILC2s. HFD reduces conventional GATA3–/loRORgt+ ILC3s, but promotes GATA3+RORgt+ ILCs, especially in Tfamf/fRorc-cre mice. Compared to conventional ILC3s, GATA3+RORgt+ ILCs express type 2 cytokines, increase cell proliferation but decrease cell death with metabolic reprograming. Single-cell transcriptional analyses indicate that GATA3+RORgt+ ILCs represent a distinct population, different from IL-17– natural ILC2s, IL-17+ inflammatory ILC2s, or conventional ILC3s. GATA3+RORgt+ ILCs produce IL-17 but not IL-22, resulting from competition of the aryl hydrocarbon receptor (Ahr) with GATA3 at the Il22 locus. Tfamf/fRorc-cre mice on HFD have worsened DSS-induced colitis. These data highlight the role of ILC metabolism in intestinal tissue remodeling and inflammation. Overall design: Live Lin–CD90.2+CD45.2+ (Lin: CD3, CD5, CD19, B220, TER119, Ly6G) cells were isolated and purified by FACS sorting from large intestine of 8 mice (Tfamf/f CD, n=2; Tfamf/fRorc-cre CD, n=2; Tfamf/f HFD, n=2; Tfamf/fRorc-cre HFD, n=2).