| First Author | Zwaferink H | Year | 2008 |
| Journal | J Immunol | Volume | 180 |
| Issue | 6 | Pages | 4116-23 |
| PubMed ID | 18322222 | Mgi Jnum | J:132928 |
| Mgi Id | MGI:3777205 | Doi | 10.4049/jimmunol.180.6.4116 |
| Citation | Zwaferink H, et al. (2008) IFN-{beta} Increases Listeriolysin O-Induced Membrane Permeabilization and Death of Macrophages. J Immunol 180(6):4116-23 |
| abstractText | 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 caspase1-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. |
