Activation of invariant NKT cells enhances the innate immune response and improves the disease course in influenza A virus infection.
Invariant NKT (iNKT) cells have an indubitable role in antiviral immunity, although the mechanisms by which these cells exert their functions are not fully elucidated. With the emerging importance of high-pathogenicity influenza A virus infections in humans, we questioned whether iNKT cells contribute to immune defence against influenza A virus and whether activation of these cells influences outcome. We show that activation of iNKT cells with alpha-galactosylceramide (alpha-GC) during influenza virus infection transiently enhanced early innate immune response without affecting T cell immunity, and reduced early viral titres in lungs of C57BL/6 mice. This is accompanied by a better disease course with improved weight loss profile. Temporal changes in iNKT cells in the liver, blood and lungs suggest activation and migration of iNKT cells from the liver to the lungs in mice that were administered alpha-GC. Improvement in viral titres appears dependent on activation of iNKT cells via the intraperitoneal route since intranasal administration of alpha-GC did not have the same effect. We conclude that activation of iNKT cells enhances early innate immune response in the lungs and contribute to antiviral immunity and improved disease course in influenza A virus infection.
MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, The John Radcliffe Hospital, Oxford, UK. Ling-pei.ho@imm.ox.ac.uk
Ling-Pei
LP
Ho
Laura
L
Denney
Kerstin
K
Luhn
Denise
D
Teoh
Colin
C
Clelland
Andrew J
AJ
McMichael
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology / Q000821:virology; D016207:Cytokines / Q000276:immunology / Q000378:metabolism*; D004195:Disease Models, Animal; D005699:Galactosylceramides / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate; D018836:Inflammation Mediators / Q000276:immunology / Q000378:metabolism*; D053118:Influenza A Virus, H1N1 Subtype / Q000254:growth & development / Q000276:immunology; D053122:Influenza A Virus, H3N2 Subtype / Q000254:growth & development / Q000276:immunology; D009980:Influenza A virus / Q000254:growth & development / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology* / Q000821:virology; D008099:Liver / Q000276:immunology; D008168:Lung / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D009976:Orthomyxoviridae Infections / Q000276:immunology / Q000821:virology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
D016207:Cytokines; D005699:Galactosylceramides; D018836:Inflammation Mediators; C493154:alpha-galactosylceramide