Salmonella enterica serovar Typhimurium-induced internalization and IL-8 expression in HeLa cells does not have a direct relationship with intracellular Ca(2+) levels.
Microbes Infect
; 11(10-11): 850-8, 2009 Sep.
Article
en En
| MEDLINE
| ID: mdl-19450704
ABSTRACT
The invasion-associated type III secretion system (T3SS-1) of S. Typhimurium is required to initiate and sustain an acute inflammatory response in the intestine. We investigated the relationship of S. Typhimurium T3SS-1-induced IL-8 expression and invasion with intracellular Ca(2+) mobilization in HeLa cells. Compared to the sipAsopABDE2 mutant, strains carrying a mutation in sipA, or mutations in sopABDE2 induced higher levels of IL-8 and greater bacterial internalization despite the fact that these mutants elicited similarly low intracellular concentrations of Ca(2+). Likewise, complemented sipAsopABDE2 mutant with sopE2 did not affect intracellular Ca(2+) concentrations or IL-8 expression, but significantly increased bacterial internalization. Treating HeLa cells with the calcium chelator BAPTA-AM or with D-BAPTA-AM, a derivative with greatly reduced Ca(2+) chelating activity, yielded strong evidence that BAPTA-AM does not affect invasion and inhibits IL-8 secretion by a calcium-dependent mechanism. These findings suggest that, although wild-type S. Typhimurium-induced IL-8 expression and bacterial internalization in HeLa cells coincides with increased cytosolic Ca(2+), the differing levels of IL-8 and invasion induced by strains carrying different effector proteins are unrelated to levels of intracellular Ca(2+).
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Salmonella typhimurium
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Calcio
/
Interleucina-8
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Citoplasma
Límite:
Humans
Idioma:
En
Revista:
Microbes Infect
Asunto de la revista:
ALERGIA E IMUNOLOGIA
/
MICROBIOLOGIA
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos