Enhanced immediate inflammatory response to Streptococcus pneumoniae in the lungs of mice with pulmonary emphysema.
Respirology
; 13(3): 324-32, 2008 May.
Article
em En
| MEDLINE
| ID: mdl-18399852
ABSTRACT
BACKGROUND AND OBJECTIVE:
Pulmonary emphysema is associated with frequent respiratory infections but little is known about the reasons for this susceptibility to bacterial infection. We previously demonstrated an impaired inflammatory response to Streptococcus pneumoniae in an experimental emphysema mouse model at 24 h, or longer following bacterial inoculation. Toll-like receptors (TLR) have been recognized as regulators in the inflammatory response. We examined the expression of TLR on alveolar macrophages in experimental emphysema mice and evaluated the immediate inflammatory response of the emphysematous lung to streptococcal infection.METHODS:
Elastase was administered once into mice trachea to induce pulmonary emphysema. Three weeks later, expression of TLR-2 and TLR-4 in the BAL cells was examined by immunostaining. Following the intratracheal inoculation of Streptococcus pneumoniae, pro-inflammatory cytokine concentrations were measured in the BAL fluids of the control and emphysema mice.RESULTS:
The expression of TLR-2 and TLR-4 was significantly elevated in the alveolar macrophages of emphysema mice. Six hours after infection, neutrophils in the BAL fluid of emphysema mice were significantly increased, and the levels of tumour necrosis factor-alpha, IL-1beta and IL-6 were significantly elevated, compared with the control mice. At 3 h post inoculation, macrophage inflammatory protein-2 levels were significantly elevated.CONCLUSIONS:
The immediate inflammatory response in the emphysematous lung is significantly enhanced in response to streptococcal infection. This may be partly attributed to the increased expression of TLR in the alveolar macrophages of emphysema mice.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Infecções Pneumocócicas
/
Pneumonia
/
Enfisema Pulmonar
/
Receptor 2 Toll-Like
/
Receptor 4 Toll-Like
/
Pulmão
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article