FIG. 3.

Flagellin-dependent IL-1β secretion by BMDM. BMDM from wild-type (A) or caspase-1-deficient (B) mice were treated with 100 ng of LPS/ml for 4 h and infected with serotype Typhimurium strains IR715 (wild-type), SW473 (fliC fljB), SW399 (invA), SW215 (flgK), or SPN315 (flgK fliC fljB) at an MOI of 5 for 18 h. The concentration of IL-1β in the culture supernatant was determined by ELISA. The data are shown as geometric means (bars) from three (A) or four (B) independent experiments ± the standard error. Strains chosen for in vivo comparison (flgK mutant and flgK fliC fljB mutant) are highlighted by black bars. ns, not statistically significant.