Activation of cytosolic phospholipase A2alpha in resident peritoneal macrophages by Listeria monocytogenes involves listeriolysin O and TLR2.
J Biol Chem
; 283(8): 4744-55, 2008 Feb 22.
Article
en En
| MEDLINE
| ID: mdl-18083708
Eicosanoid production by macrophages is an early response to microbial infection that promotes acute inflammation. The intracellular pathogen Listeria monocytogenes stimulates arachidonic acid release and eicosanoid production from resident mouse peritoneal macrophages through activation of group IVA cytosolic phospholipase A2 (cPLA2alpha). The ability of wild type L. monocytogenes (WTLM) to stimulate arachidonic acid release is partially dependent on the virulence factor listeriolysin O; however, WTLM and L. monocytogenes lacking listeriolysin O (DeltahlyLM) induce similar levels of cyclooxygenase 2. Arachidonic acid release requires activation of MAPKs by WTLM and DeltahlyLM. The attenuated release of arachidonic acid that is observed in TLR2-/- and MyD88-/- macrophages infected with WTLM and DeltahlyLM correlates with diminished MAPK activation. WTLM but not DeltahlyLM increases intracellular calcium, which is implicated in regulation of cPLA2alpha. Prostaglandin E2, prostaglandin I2, and leukotriene C4 are produced by cPLA2alpha+/+ but not cPLA2alpha-/- macrophages in response to WTLM and DeltahlyLM. Tumor necrosis factor (TNF)-alpha production is significantly lower in cPLA2alpha+/+ than in cPLA2alpha-/- macrophages infected with WTLM and DeltahlyLM. Treatment of infected cPLA2alpha+/+ macrophages with the cyclooxygenase inhibitor indomethacin increases TNFalpha production to the level produced by cPLA2alpha-/- macrophages implicating prostaglandins in TNFalpha down-regulation. Therefore activation of cPLA2alpha in macrophages may impact immune responses to L. monocytogenes.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Toxinas Bacterianas
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Macrófagos Peritoneales
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Factores de Virulencia
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Receptor Toll-Like 2
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Fosfolipasas A2 Grupo IV
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Proteínas de Choque Térmico
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Proteínas Hemolisinas
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Listeriosis
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Listeria monocytogenes
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Activación de Macrófagos
Idioma:
En
Revista:
J Biol Chem
Año:
2008
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos