PT  - JOURNAL ARTICLE
AU  - Girard, M.
AU  - Israël-Assayag, E.
AU  - Cormier, Y.
TI  - Mature CD11c<sup>+</sup> cells are enhanced in hypersensitivity pneumonitis
AID  - 10.1183/09031936.00140908
DP  - 2009 Sep 01
TA  - European Respiratory Journal
PG  - 749--756
VI  - 34
IP  - 3
4099  - http://erj.ersjournals.com/content/34/3/749.short
4100  - http://erj.ersjournals.com/content/34/3/749.full
SO  - Eur Respir J2009 Sep 01; 34
AB  - 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.