Fig. 4.

Deletion of prgH did not influence the synthesis of inflammasome components. C57BL/6 BMDMs were pre-treated with LPS (1 μg/mL) for 5 h (untreated and uninfected BMDMs was used as a negative control, Blank LPS-), and then infected with C50336, C50336ΔprgH, C50336ΔprgH::prgH, C50336ΔprgH-pMMB207, C50336::prgH, or C50336-pMMB207 at an MOI of 20 for 4 h, uninfected BMDMs was used as another negative control (Blank LPS+). Bacteria bearing pMMB207 plasmids were cultured with IPTG (0.5 mM). a. The ratio of cell death was evaluated by the release of LDH in the supernatants. b. The expression of caspase-1, NLRP3, NLRC4, ASC, and pro-IL-1β were analyzed by immunoblotting. β-actin was blotted as a loading control. Molecular mass markers in kDa are indicated on the right. Original images of immunoblotting were shown in Fig. S4. The production of IL-1β c and IL-6 d in the supernatants were examined via ELISA. ***p < 0.001 for one-way ANOVA followed by Bonferroni’s multiple comparison test indicate significant findings in comparison with cells infected with WT strain C50336. Data are presented as mean ± SEM of triplicate samples per experimental condition from three independent experiments