Interleukin 1 receptor-associated kinase m impairs host defense during pneumococcal pneumonia.
J Infect Dis
; 205(12): 1849-57, 2012 Jun 15.
Article
em En
| MEDLINE
| ID: mdl-22492852
ABSTRACT
BACKGROUND:
Streptococcus pneumoniae is the most common causative organism in community-acquired pneumonia. Pneumococci that try to invade the lower airways are recognized by innate immune cells through pattern recognition receptors, including Toll-like receptors 2, 4, and 9. Interleukin 1 (IL-1) receptor-associated kinase (IRAK)-M is a proximal inhibitor of Toll-like receptor signaling.METHODS:
To determine the role of IRAK-M in host defense during pneumococcal pneumonia, IRAK-M- deficient and wild-type mice were intranasally infected with S. pneumoniae.RESULTS:
IRAK-M-deficient mice demonstrated a reduced lethality after infection with S. pneumoniae via the airways. Whereas bacterial burdens were similar in IRAK-M-deficient and wild-type mice early (3 hours) after infection, from 24 hours onward the number of pneumococci recovered from lungs and distant body sites were 10-100-fold lower in the former mouse strain. The diminished bacterial growth and dissemination in IRAK-M-deficient mice were preceded by an increased early influx of neutrophils into lung tissue and elevated pulmonary levels of IL-1ß and CXCL1. IRAK-M deficiency did not influence bacterial growth after intravenous administration of S. pneumoniae.CONCLUSIONS:
These data suggest that IRAK-M impairs host defense during pneumococcal pneumonia at the primary site of infection at least in part by inhibiting the early immune response.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pneumonia Pneumocócica
/
Streptococcus pneumoniae
/
Quinases Associadas a Receptores de Interleucina-1
/
Interações Hospedeiro-Patógeno
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
J Infect Dis
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Holanda