Bertschi, Nicole LeonieNicole LeonieBertschiSteck, OliverOliverSteckLuther, Fabian UrsFabian UrsLuther0000-0002-0669-9460Bazzini, CeciliaCeciliaBazzinivon Meyenn, Karl-LeonhardKarl-Leonhardvon Meyenn0000-0003-2490-1412Schärli, StefanieStefanieSchärliVallone, AngelaAngelaValloneFelser, Andrea DeboraAndrea DeboraFelserKeller, IreneIreneKellerFriedli, OlivierOlivierFriedliFreigang, StefanStefanFreigang0000-0003-4438-7828Begré, NadjaNadjaBegréRadonjic, Susanne IreneSusanne IreneRadonjicLamos, CristinaCristinaLamosGabutti, Max PhilipMax PhilipGabuttiBenzaquen, Michael JosephMichael JosephBenzaquenLaimer, MarkusMarkusLaimer0000-0002-7622-0822Simon, DagmarDagmarSimonNuoffer, Jean-MarcJean-MarcNuoffer0000-0003-3650-6153Schlapbach, ChristophChristophSchlapbach2024-10-252024-10-252023-04-29https://boris-portal.unibe.ch/handle/20.500.12422/166776T helper 9 (TH9) cells promote allergic tissue inflammation and express the type 2 cytokines, IL-9 and IL-13, as well as the transcription factor, PPAR-γ. However, the functional role of PPAR-γ in human TH9 cells remains unknown. Here, we demonstrate that PPAR-γ drives activation-induced glycolysis, which, in turn, promotes the expression of IL-9, but not IL-13, in an mTORC1-dependent manner. In vitro and ex vivo experiments show that the PPAR-γ-mTORC1-IL-9 pathway is active in TH9 cells in human skin inflammation. Additionally, we find dynamic regulation of tissue glucose levels in acute allergic skin inflammation, suggesting that in situ glucose availability is linked to distinct immunological functions in vivo. Furthermore, paracrine IL-9 induces expression of the lactate transporter, MCT1, in TH cells and promotes their aerobic glycolysis and proliferative capacity. Altogether, our findings uncover a hitherto unknown relationship between PPAR-γ-dependent glucose metabolism and pathogenic effector functions in human TH9 cells.en600 - Technology::610 - Medicine & health500 - Science::570 - Life sciences; biologyarticle10.48350/1821293712058210.1038/s41467-023-38233-x