title: Long-term deposition of inhaled antigen in lung resident CD11b-CD11c+ cells.
abstract: In this study we report the characterization of a population of lung resident CD11b(-)CD11c(+) cells that are able to take up inhaled antigen and retain it for extended periods of time. Ovalbumin conjugated to fluorescein-isothiocyanate (FITC-OVA) administered intranasally to mice was taken up by two main populations of cells in the lung, a migratory CD11c(+)CD11b(+) population consisting of dendritic cells (DC), which rapidly transported antigen to the draining lymph node (LN), and a resident CD11b(-)CD11c(+) population that retained engulfed antigen without apparently degrading it for up to 8 wk after administration. The FITC(+)CD11b(-)CD11c(+) cells did not migrate to draining LN at a detectable rate, and did not up-regulate expression of costimulatory molecules in response to LPS treatment. FITC(+)CD11b(-)CD11c(+) cells were found in the lung and bronchoalveolar lavage fluid, and their distribution was compatible with macrophages. Although FITC(+)CD11b(-)CD11c(+) cells expressed the DC marker DEC205 and other molecules associated with antigen-presenting cell function, they did not induce proliferation of antigen-specific CD4(+) T cells in vitro or acute cytokine production by activated CD4(+) T cells in vivo. Thus, FITC(+)CD11b(-)CD11c(+) cells appear to represent an intermediate cell type sharing properties with DC and macrophages. These cells may have a role in modulating the responses of lung resident T cells to inhaled antigens.
authors.affiliation: Malaghan Institute of Medical Research, PO Box 7060, Wellington South, New Zealand.
authors.forename: Kate E
authors.initials: KE
authors.lastname: Matthews
authors.forename: Adela
authors.initials: A
authors.lastname: Karabeg
authors.forename: Joanna M
authors.initials: JM
authors.lastname: Roberts
authors.forename: Sem
authors.initials: S
authors.lastname: Saeland
authors.forename: Gerhard
authors.initials: G
authors.lastname: Dekan
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Epstein
authors.forename: Franca
authors.initials: F
authors.lastname: Ronchese
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000941:Antigens / Q000008:administration & dosage*; D039481:CD11b Antigen / Q000378:metabolism*; D039521:CD11c Antigen / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology; D004802:Eosinophilia / Q000276:immunology; D016650:Fluorescein-5-isothiocyanate / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008168:Lung / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D008198:Lymph Nodes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D010047:Ovalbumin / Q000008:administration & dosage; D015854:Up-Regulation
chemical_list: D000941:Antigens; D039481:CD11b Antigen; D039521:CD11c Antigen; D008070:Lipopolysaccharides; D010047:Ovalbumin; D016650:Fluorescein-5-isothiocyanate