IL18 and infection: After 12 h, the relative expression of TNFα, iNOS, IL-1β, and IL-18 in the ΔhtpG infection group was significantly lower than that in the WT infection group (p < 0.01), and the relative expression of IL-1β and IL-18 was extremely lower than that in the CΔhtpG infection group (p < 0.01).