Fig. 8: Klebsiella pneumoniae-mediated induction of protective pyroptosis via inflammasome activation.

The A28006 strain activates inflammasome through bacterial components and caspase-11, triggering inflammasome formation, which allows caspase-1 activation. Therefore, there is the cleavage of pro-IL-1β in mature IL-1β. In addition, there is induction of cell death by pyroptosis, culminating in pore formation and release of intracellular soluble components, such as LDH. IL-1β together with other mediators are capable to recruit new cells to the infection site, promoting efferocytosis of pyroptotic-infected cells and bacterial clearance. Nevertheless, IL-10 production inhibits inflammasome activation, impairing inflammasome formation and cell death by pyroptosis and the efferocytosis of infected cells. This phenomenon, in our model, seems to impair an efficient resolution of infection and allow bacterial dissemination