Figure 1. Danger-associated signaling via the inflammasome.

(A) Cytosolic microbe-associated molecular patterns and danger signals are detected and integrated by an array of inflammasome components converging at the activation of caspase-1 [5], [38]–[40]. In addition to the already known stimuli for inflammasome activation (left, red), a pathway involving S. Typhimurium SopE and Rho GTPases (right, blue) has been described recently [8]. (B) Comparison of the virulence mechanisms of Salmonella spp., Shigella spp., and Citrobacter/EPEC. The effector proteins injected can act both directly on the actin polymerization as well as via the activation of Rho GTPases [41]–[43]. (C) Comparison of pathologies in different animal models of Salmonella, Shigella, and Citrobacter/EPEC infection. The region of the strongest pathology and the most important pathological changes in each model is indicated in red. Representative images for the macroscopic and histological changes in the respective animal models can be found in references [44]–[48].