title: NK T cells contribute to expansion of CD8(+) T cells and amplification of antiviral immune responses to respiratory syncytial virus.
abstract: CD1d-deficient mice have normal numbers of T lymphocytes and natural killer cells but lack Valpha14(+) natural killer T cells. Respiratory syncytial virus (RSV) immunopathogenesis was evaluated in 129xC57BL/6, C57BL/6, and BALB/c CD1d(-/-) mice. CD8(+) T lymphocytes were reduced in CD1d(-/-) mice of all strains, as shown by cell surface staining and major histocompatibility complex class I tetramer analysis, and resulted in strain-specific alterations in illness, viral clearance, and gamma interferon (IFN-gamma) production. Transient activation of NK T cells in CD1d(+/+) mice by alpha-GalCer resulted in reduced illness and delayed viral clearance. These data suggest that early IFN-gamma production and efficient induction of CD8(+)-T-cell responses during primary RSV infection require CD1d-dependent events. We also tested the ability of alpha-GalCer as an adjuvant to modulate the type 2 immune responses induced by RSV glycoprotein G or formalin-inactivated RSV immunization. However, immunized CD1-deficient or alpha-GalCer-treated wild-type mice did not exhibit diminished disease following RSV challenge. Rather, some disease parameters, including cytokine production, eosinophilia, and viral clearance, were increased. These findings indicate that CD1d-dependent NK T cells play a role in expansion of CD8(+) T cells and amplification of antiviral responses to RSV.
authors.affiliation: Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
authors.forename: Teresa R
authors.initials: TR
authors.lastname: Johnson
authors.forename: Seokmann
authors.initials: S
authors.lastname: Hong
authors.forename: Luc
authors.initials: L
authors.lastname: Van Kaer
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Koezuka
authors.forename: Barney S
authors.initials: BS
authors.lastname: Graham
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D018949:Antigens, CD1 / Q000235:genetics / Q000378:metabolism*; D055610:Antigens, CD1d; D005699:Galactosylceramides / Q000276:immunology; D007114:Immunization; D007694:Killer Cells, Natural / Q000276:immunology*; D008024:Ligands; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D022261:Respiratory Syncytial Virus Vaccines / Q000276:immunology; D012136:Respiratory Syncytial Viruses / Q000276:immunology* / Q000472:pathogenicity; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology
chemical_list: D018949:Antigens, CD1; D055610:Antigens, CD1d; D005699:Galactosylceramides; D008024:Ligands; D022261:Respiratory Syncytial Virus Vaccines; D014764:Viral Proteins