title: Immune surveillance of the lung by migrating tissue monocytes.
abstract: Monocytes are phagocytic effector cells in the blood and precursors of resident and inflammatory tissue macrophages. The aim of the current study was to analyse and compare their contribution to innate immune surveillance of the lung in the steady state with macrophage and dendritic cells (DC). ECFP and EGFP transgenic reporters based upon Csf1r and Cx3cr1 distinguish monocytes from resident mononuclear phagocytes. We used these transgenes to study the migratory properties of monocytes and macrophages by functional imaging on explanted lungs. Migratory monocytes were found to be either patrolling within large vessels of the lung or locating at the interface between lung capillaries and alveoli. This spatial organisation gives to monocytes the property to capture fluorescent particles derived from both vascular and airway routes. We conclude that monocytes participate in steady-state surveillance of the lung, in a way that is complementary to resident macrophages and DC, without differentiating into macrophages.
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Mathieu P
authors.initials: MP
authors.lastname: Rodero
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Poupel
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Pierre-Louis
authors.initials: PL
authors.lastname: Loyher
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Hamon
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Licata
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Pessel
authors.affiliation: Royal (Dick) School of Veterinary Studies, The Roslin Institute, Midlothian, United Kingdom.
authors.forename: David A
authors.initials: DA
authors.lastname: Hume
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Combadière
authors.affiliation: Centre d'Immunologie et des Maladies Infectieuses, University Pierre et Marie Curie, Sorbonne Universities, Paris, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Boissonnas
mesh_terms: D000818:Animals; D002465:Cell Movement; D003713:Dendritic Cells / Q000276:immunology; D017930:Genes, Reporter; D007113:Immunity, Innate; D008168:Lung / Q000276:immunology*; D008822:Mice, Transgenic; D009000:Monocytes / Q000276:immunology* / Q000502:physiology
keywords: cell biology; immunology; innate immunity; live imaging; lung immunology; monocytes; mouse