Journalartikel

Jahr der Veröffentlichung: 1996

Seiten: 4055-4060

Zeitschrift: The Journal of Immunology

Bandnummer: 157

Heftnummer: 9

ISSN: 0022-1767

Verlag: American Association of Immunologists

Abstract: 
Exotoxins such as listeriolysin (LLO) and phosphatidylinositol-specific phospholipase C (PlcA) have been implicated in listerial infection and sepsis, Employing different Listeria strains, mutated in individually known virulence genes, we examined exotoxin-related induction of endothelial cell signaling, Listeria monocytogenes was a potent inductor of phosphatidylinositol (Ptdlns) metabolism in HUVEC. This effect was completely absent in a LLO-negative strain, Using a recombinant Listeria innocua strain, engineered to produce high levels of LLO, Ptdlns metabolism was restored to similar to 30% of that produced by the parental L. monocytogenes strain, A recombinant L. innocua strain expressing only PlcA did not induce any Ptdlns metabolism, Even higher than wild-type levels of Ptdlns hydrolysis products were, however, evoked when engineered bacteria secreted both LLO and PlcA, These effects occurred in the absence of bacterial uptake by the endothelial cells, Corresponding results were observed with regard to endothelial diacylglycerol (DAC) generation, The amplification of endothelial cell signaling could be reproduced by engaging purified LLO and PlcA in the absence of bacteria, In these experiments, the unrelated performing agent staphylococcal a-toxin, a very weak stimulus for endothelial phosphoinositide metabolism by itself, substituted for LLO to allow marked Ptdlns hydrolysis when co-applied with PlcA, We conclude that the listerial exotoxins LLO and PlcA cooperate to provoke potent second messenger synthesis in endothelial cells, in the absence of cell invasion by the bacteria, This is an impressive example of synergism between a pore-forming and an enzymatic bacterial exotoxin in prove king cell signaling and inflammatory events.

Harvard-Zitierstil: Sibelius, U., Chakraborty, T., Krogel, B., Wolf, J., Rose, F., Schmidt, R., et al. (1996) The listerial exotoxins listeriolysin and phosphatidylinositol-specific phospholipase C synergize to elicit endothelial cell phosphoinositide metabolism, The Journal of Immunology, 157(9), pp. 4055-4060

APA-Zitierstil: Sibelius, U., Chakraborty, T., Krogel, B., Wolf, J., Rose, F., Schmidt, R., Wehland, J., Seeger, W., & Grimminger, F. (1996). The listerial exotoxins listeriolysin and phosphatidylinositol-specific phospholipase C synergize to elicit endothelial cell phosphoinositide metabolism. The Journal of Immunology. 157(9), 4055-4060.