title: Mature CD11c(+) cells are enhanced in hypersensitivity pneumonitis.
abstract: The present study verified the hypothesis that enhanced maturation of antigen-presenting CD11c(+) cells could explain the viral-induced exacerbated immune response to Saccharopolyspora rectivirgula (SR), the main antigen responsible for farmer's lung, a classic form of hypersensitivity pneumonitis (HP). Four groups of mice were studied: group 1 received intranasal instillations of saline; group 2 received instillations of SR for 12 weeks; group 3 received instillations of saline and a single infection with Sendai virus on week 3; and group 4 received instillations of SR for 12 weeks with a single administration of Sendai virus on week 3. On week 13, mice were sacrificed and bronchoalveolar lavage was performed. Lungs were harvested, digested with enzymes, and CD11c(+) cells were analysed in flow cytometry with anti-CD11c, anti-CD86 and anti-major histocompatibility complex class II markers. Immunofluorescence studies were also performed with the same cell surface markers. Both flow cytometry and immunofluorescence results demonstrate that mature CD11c(+) cells are significantly enhanced in SR-challenged mice simultaneously infected with Sendai virus, compared with other groups. These CD11c(+) cells persist in the lung for 9 weeks after the virus infection. Maturation of CD11c(+) cells could explain, at least in part, the virus-induced increased immune response to SR antigens in this model of HP, but mechanisms have still to be elucidated.
authors.affiliation: Centre de recherche de l'Institute universitaire de cardiologie et de pneumologie de Québec, Quebec City, QC, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Girard
authors.forename: E
authors.initials: E
authors.lastname: Israël-Assayag
authors.forename: Y
authors.initials: Y
authors.lastname: Cormier
mesh_terms: D000542:Alveolitis, Extrinsic Allergic / Q000276:immunology* / Q000382:microbiology / Q000473:pathology*; D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology*; D051940:B7-2 Antigen / Q000378:metabolism; D039521:CD11c Antigen / Q000502:physiology*; D004195:Disease Models, Animal; D005260:Female; D006681:HLA-D Antigens / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D010253:Respirovirus Infections / Q000150:complications / Q000276:immunology / Q000378:metabolism; D016930:Saccharopolyspora / Q000276:immunology*; D029082:Sendai virus / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D051940:B7-2 Antigen; D039521:CD11c Antigen; C497965:Cd86 protein, mouse; D006681:HLA-D Antigens