title: Neutrophils sustain effective CD8(+) T-cell responses in the respiratory tract following influenza infection.
abstract: Neutrophils have an important role in early host protection during influenza A virus infection. Their ability to modulate the virus-specific adaptive immune response is less clear. Here, we have used a mouse model to examine the impact of neutrophils on CD8(+) T-cell responses during influenza virus infection. CD8(+) T-cell priming, expansion, migration, cytokine secretion and cytotoxic capacity were investigated in the virus-infected airways and secondary lymphoid organs. To do this, we utilised a Ly6G-specific monoclonal antibody (mAb; 1A8) that specifically depletes neutrophils in vivo. Neutrophil depletion early after infection with influenza virus strain HKx31 (H3N2) did not alter influenza virus-derived antigen presentation or naïve CD8(+) T-cell expansion in the secondary lymphoid organs. Trafficking of virus-specific CD8(+) T cells into the infected pulmonary airways was also unaltered. Instead, early neutropenia reduced both the overall magnitude of influenza virus-specific CD8(+) T cells, together with impaired cytokine production and cytotoxic effector function. Therefore, neutrophils are important participants in anti-viral mechanisms that sustain effective CD8(+) T-cell responses in the respiratory tract of influenza virus-infected mice.
authors.affiliation: Department of Microbiology and Immunology, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Tate
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Brooks
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Reading
authors.forename: Justine D
authors.initials: JD
authors.lastname: Mintern
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002465:Cell Movement / Q000276:immunology; D049109:Cell Proliferation; D053804:Granzymes / Q000032:analysis; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology / Q000472:pathogenicity; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D012137:Respiratory System / Q000276:immunology* / Q000473:pathology / Q000821:virology
chemical_list: D000911:Antibodies, Monoclonal; D053804:Granzymes