Klebsiella pneumoniae targets an EGF receptor-dependent pathway to subvert inflammation.
Cell Microbiol
; 15(7): 1212-33, 2013 Jul.
Article
em En
| MEDLINE
| ID: mdl-23347154
ABSTRACT
The NF-κB transcriptional factor plays a key role governing the activation of immune responses. Klebsiella pneumoniae is an important cause of community-acquired and nosocomial pneumonia. Evidence indicates that K. pneumoniae infections are characterized by lacking an early inflammatory response. Recently, we have demonstrated that Klebsiella antagonizes the activation of NF-κB via the deubiquitinase CYLD. In this work, by applying a high-throughput siRNA gain-of-function screen interrogating the human kinome, we identified 17 kinases that when targeted by siRNA restored IL-1ß-dependent NF-κB translocation in infected cells. Further characterization revealed that K. pneumoniae activates an EGF receptor (EGFR)-phosphatidylinositol 3-OH kinase (PI3K)-AKT-PAK4-ERK-GSK3ß signalling pathway to attenuate the cytokine-dependent nuclear translocation of NF-κB. Our data also revealed that CYLD is a downstream effector of K. pneumoniae-induced EGFR-PI3K-AKT-PAK4-ERK-GSK3ß signalling pathway. Our efforts to identify the bacterial factor(s)responsible for EGFR activation demonstrate that a capsule (CPS) mutant did not activate EGFR hence suggesting that CPS could mediate the activation of EGFR. Supporting this notion, purified CPS did activate EGFR as well as the EGFR-dependent PI3K-AKT-PAK4-ERK-GSK3ß signalling pathway. CPS-mediated EGFR activation was dependent on a TLR4-MyD88-c-SRC-dependent pathway. Several promising drugs have been developed to antagonize this cascade. We propose that agents targeting this signalling pathway might provide selective alternatives for the management of K. pneumoniae pneumonias.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Quinases
/
Transdução de Sinais
/
Interações Hospedeiro-Patógeno
/
Evasão da Resposta Imune
/
Receptores ErbB
/
Klebsiella pneumoniae
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article