IFN-beta increases listeriolysin O-induced membrane permeabilization and death of macrophages.
J Immunol
; 180(6): 4116-23, 2008 Mar 15.
Article
en En
| MEDLINE
| ID: mdl-18322222
ABSTRACT
Type I IFN (IFN-I) signaling is detrimental to cells and mice infected with Listeria monocytogenes. In this study, we investigate the impact of IFN-I on the activity of listeriolysin O (LLO), a pore-forming toxin and virulence protein released by L. monocytogenes. Treatment of macrophages with IFN-beta increased the ability of sublytic LLO concentrations to cause transient permeability of the plasma membrane. At higher LLO concentrations, IFN-beta enhanced the complete breakdown of membrane integrity and cell death. This activity of IFN-beta required Stat1. Perturbation of the plasma membrane by LLO resulted in activation of the p38MAPK pathway. IFN-beta pretreatment enhanced LLO-mediated signaling through this pathway, consistent with its ability to increase membrane damage. p38MAPK activation in response to LLO was independent of TLR4, a putative LLO receptor, and inhibition of p38MAPK neither enhanced nor prevented LLO-induced death. IFN-beta caused cells to express increased amounts of caspase 1 and to produce a detectable caspase 1 cleavage product after LLO treatment. Contrasting recent reports with another pore-forming toxin, this pathway did not aid cell survival as caspase 1-deficient cells were equally sensitive to lysis by LLO. Key lipogenesis enzymes were suppressed in IFN-beta-treated cells, which may exacerbate the membrane damage caused by LLO.
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Base de datos:
MEDLINE
Asunto principal:
Regulación hacia Arriba
/
Permeabilidad de la Membrana Celular
/
Interferón beta
/
Proteínas de Choque Térmico
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Proteínas Hemolisinas
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Macrófagos
Idioma:
En
Revista:
J Immunol
Año:
2008
Tipo del documento:
Article