Fig. 1: Salmonella pSLT-encoded effector SpvB induces caspase‐independent cell death.

A Caco-2 cells were infected with the WT, ΔspvB, or ΔspvB/pspvB S. Typhimurium strain (MOI of 100) and incubated for 2, 4, 16, and 24 h. Aliquots of cellular supernatants were subjected to LDH release assay. B, C Caco-2 cells were infected with the WT, ΔspvB, or ΔspvB/pspvB S. Typhimurium strain (MOI of 100) and incubated for 4 h. B Cells were harvested and subjected to measurement of caspase-3 activity. C Western blot analysis of the expression of cleaved GSDMD. D Caco-2 cells were treated with either vehicle (DMSO) or 20 μM Z-VAD-FMK for 1 h. The cells were then infected with WT, ΔspvB, or ΔspvB/pspvB S. Typhimurium strain (MOI of 100) and incubated for 24 h. Aliquots of cellular supernatants were subjected to LDH release assay. Data were analyzed with IBM SPSS Statistics 19 and presented as the mean ± SEM using Student’s t-test and ANOVA with S-N-K correction. *P < 0.05; ns, not significant.