Bonnie Van WilgenburgIris ScherwitzlEdward C. HutchinsonTianqi LengAyako KuriokaCorinna KulickeCatherine De LaraSuzanne ColeSirijitt VasanawathanaWannee LimpitikulPrida MalasitDuncan YoungLaura DenneyMichael D. MoorePaolo FabrisMaria Teresa GiordaniYe Htun OoStephen M. LaidlawLynn B. DustinLing Pei HoFiona M. ThompsonNarayan RamamurthyJuthathip MongkolsapayaChristian B. WillbergGavin R. ScreatonPaul KlenermanEleanor BarnesJonathan BallGary BurgessGraham CookeJohn DillonCharles GoreGraham FosterNeil GuhaRachel HalfordCham HerathChris HolmesAnita HoweEmma HudsonWilliam IrvingSalim KhakooDiana KoletzkiNatasha MartinTamyo MbisaJane McKeatingJohn McLauchlanAlec MinersAndrea MurrayPeter ShawPeter SimmondsChris SpencerPaul Targett-AdamsEmma ThomsonPeter VickermanNicole ZitzmannNuffield Department of Clinical MedicineImperial College LondonSir William Dunn School of PathologyKhon Kaen Regional HospitalSongkhla HospitalThailand National Center for Genetic Engineering and BiotechnologyMahidol UniversityJohn Radcliffe HospitalOspedale San BortoloUniversity of BirminghamKennedy Institute of RheumatologyUniversity of OxfordUniversity of NottinghamConatus PharmaceuticalsUniversity of Dundee College of Medicine, Dentistry and NursingHepatitis C TrustQueen Mary, University of LondonGilead Sciences LtdSt. Paul's HospitalUniversity of SouthamptonJanssen DiagnosticsUniversity of California, San DiegoPublic Health EnglandUniversity of GlasgowLondon School of Hygiene & Tropical MedicineNottingham City HospitalMerck & Co., Inc.Wellcome Trust Centre for Human GeneticsMedivir ABUniversity of Bristol2018-12-112019-03-142018-12-112019-03-142016-06-23Nature Communications. Vol.7, (2016)204117232-s2.0-84975705227https://repository.li.mahidol.ac.th/handle/20.500.14594/42998Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation - driving cytokine release and Granzyme B upregulation - is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/β. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyChemistryArticleSCOPUS10.1038/ncomms11653