title: Cutting edge: pulmonary Legionella pneumophila is controlled by plasmacytoid dendritic cells but not type I IFN.
abstract: Plasmacytoid dendritic cells (pDCs) are well known as the major cell type that secretes type I IFN in response to viral infections. Their role in combating other classes of infectious organisms, including bacteria, and their mechanisms of action are poorly understood. We have found that pDCs play a significant role in the acute response to the intracellular bacterial pathogen Legionella pneumophila. pDCs were rapidly recruited to the lungs of L. pneumophila-infected mice, and depletion of pDCs resulted in increased bacterial load. The ability of pDCs to combat infection did not require type I IFN. This study points to an unappreciated role for pDCs in combating bacterial infections and indicates a novel mechanism of action for this cell type.
authors.affiliation: Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Australia.
authors.forename: Desmond K Y
authors.initials: DK
authors.lastname: Ang
authors.forename: Clare V L
authors.initials: CV
authors.lastname: Oates
authors.forename: Ralf
authors.initials: R
authors.lastname: Schuelein
authors.forename: Michelle
authors.initials: M
authors.lastname: Kelly
authors.forename: Fiona M
authors.initials: FM
authors.lastname: Sansom
authors.forename: Dorothée
authors.initials: D
authors.lastname: Bourges
authors.forename: Louis
authors.initials: L
authors.lastname: Boon
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Hertzog
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Hartland
authors.forename: Ian R
authors.initials: IR
authors.lastname: van Driel
mesh_terms: D000818:Animals; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D007370:Interferon Type I / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D016952:Legionella pneumophila / Q000254:growth & development / Q000276:immunology*; D008168:Lung / Q000166:cytology / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D053633:Receptor, Interferon alpha-beta / Q000172:deficiency / Q000235:genetics
chemical_list: C508034:Ifnar2 protein, mouse; D007370:Interferon Type I; D053633:Receptor, Interferon alpha-beta