Roles of interleukin-17 in an experimental Legionella pneumophila pneumonia model.
Infect Immun
; 80(3): 1121-7, 2012 Mar.
Article
em En
| MEDLINE
| ID: mdl-22144493
ABSTRACT
Interleukin-17 (IL-17) is a key factor in T helper type 17 (Th17) lineage host responses and plays critical roles in immunological control of a variety of infectious diseases. Although Legionella pneumophila, an intracellular bacterium found widely in the environment, often causes a serious and life-threatening pneumonia in humans, the contribution of IL-17 to immune function during Legionella pneumonia is unknown. In the present study, we used an experimental Legionella pneumonia infection to clarify the role of IL-17 in the resulting immune response. We observed robust production of pulmonary IL-17A and IL-17F (IL-17A/F), peaking on day 1 and declining thereafter. Upregulated production of tumor necrosis factor alpha (TNF-α), IL-6, and IL-1ß, but not monocyte chemotactic protein 1 (MCP-1), was observed in Legionella-infected bone marrow-derived macrophages from BALB/c mice that had been stimulated with IL-17A or IL-17F. A significant decrease in the production of proinflammatory cytokines IL-6 and TNF-α was observed in IL-17A/F-deficient mice (BALB/c background) infected with L. pneumophila. Moreover, we found impaired neutrophil migration and lower numbers of chemokines (KC, LIX, and MIP-2) in IL-17A/F-deficient mice. IL-17A/F-deficient mice also eliminated L. pneumophila more slowly and were less likely to survive a lethal challenge. These results demonstrate that IL-17A/F plays a critical role in L. pneumophila pneumonia, probably through induction of proinflammatory cytokines and accumulation of neutrophils at the infection site.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Doença dos Legionários
/
Legionella pneumophila
/
Interleucina-17
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Infect Immun
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Japão