IL18 and infection: Surprisingly, plasma IFN-γ levels (Figure 2B) did not differ between WT and Asc−/− mice during S. Typhimurium infection (2 and 5 days post-infection) despite the observed marked differences in release of IL-18, which is a key trigger for IFN-γ release via NK and T-cells, dendritic and other phagocytic cells during Salmonella infection [14,15].