Switching Rho GTPase activation into effective antibacterial defenses requires the caspase-1/IL-1beta signaling axis.
The monitoring of the activation state of Rho GTPases has emerged as a potent innate immune mechanism for detecting pathogens. In the March issue of PLOS Pathogens, we show that the activation of Rho GTPases by the CNF1 toxin during E. coli-triggered bacteremia leads to a GR1(+)cell-mediated efficient bacterial clearing and improves host survival. Host alarm requires the Caspase-1/IL-1beta signaling axis. Furthermore, we discover that pathogenic bacteria have the capacity to block immune responses via the expression of the α-hemolysin pore-forming toxin. In this commentary, we will comment on these findings and highlight the questions raised by this example of attack-defense mechanisms used alternatively by the pathogen and the host during blood infection.
a INSERM; U1065; Center Méditerranéen de Médecine Moléculaire; C3M; Toxines Microbiennes dans la relation hôte pathogènes; Equipe Labellisée Ligue Contre le Cancer ; Nice , France.|b Université de Nice-Sophia-Antipolis; UFR Médecine ; Nice , France.
Laurent
L
Boyer
a INSERM; U1065; Center Méditerranéen de Médecine Moléculaire; C3M; Toxines Microbiennes dans la relation hôte pathogènes; Equipe Labellisée Ligue Contre le Cancer ; Nice , France.|b Université de Nice-Sophia-Antipolis; UFR Médecine ; Nice , France.
Emmanuel
E
Lemichez
D000818:Animals; D001427:Bacterial Toxins / Q000276:immunology; D020170:Caspase 1 / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000276:immunology* / Q000473:pathology; D029968:Escherichia coli Proteins / Q000276:immunology; D006460:Hemolysin Proteins / Q000276:immunology; D006801:Humans; D053583:Interleukin-1beta / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology*; D054460:rho-Associated Kinases / Q000276:immunology*
D001427:Bacterial Toxins; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; C508585:IL1B protein, human; D053583:Interleukin-1beta; C060296:cytotoxic necrotizing factor type 1; D054460:rho-Associated Kinases; D020170:Caspase 1
Il-1beta; antibacterial defenses; bacterial effectors; bacterial toxins; caspase-1; effector-triggered immunity; innate immunity