Figure 1.

EPEC Induces Rapid, NLRP3-Dependent Pyroptosis and Cytokine Processing in Human Monocyte-Derived Macrophages and THP1 Cells

(A) Primary human monocyte-derived macrophage (MDMs) were infected with DMEM-primed wild-type (WT) or T3SS-deficient ΔescF EPEC for 4 h. Pyroptosis measured by lactate dehydrogenase (LDH) release (n = 6 independent repeats from four donors) is plotted on top in (A) and representative immunoblots for indicated proteins are shown below.

(B and C) Primary MDMs were left uninfected (UI) or infected with WT EPEC without or with MCC950 (5 μM). LDH release assay (B) and representative immunoblots (C) are shown (n = 5 independent repeats from four donors).

(D–F) THP1 cells were left UI or infected with DMEM-primed indicated strains of EPEC (WT or T3SS-deficient ΔescF) for 4 h (D and F) or up to 5 h (E). The graph in (E) shows real-time propidium iodide (PI) uptake (means ± SEMs; n = 3 independent experiments). MCC950 was used at 5 μM. ^∗∗p < 0.01, ^∗∗∗∗p < 0.0001 by two-way ANOVA with false discovery rate (FDR)-based correction for multiple comparisons.

The matching shapes and colors of symbols in graphs in (A) and (B) denote data from independent donors and/or experiments. Immunoblots (A, C, D, and F) are representative of experiments performed at least three times. ^∗∗p < 0.01, ^∗∗∗p < 0.001 by two-tailed paired Student’s t test.