E. coli induces TNF-α secretion which is involved in induction of apoptosis in PBMO and CBMO.

Assessment of secreted TNF-α 4 h p.i. from supernatants of PBMO and CBMO (A, n = 7; ***p < 0.005, clamped bars, student`s t-test; ***p < 0.005, blunt-ended bars, two-way ANOVA). Induction of apoptosis 4 h p.i. assessed by Nicoletti assay in CD14+ monocytes after indicated treatment (B, n = 8; *p < 0.05, clamped bars, student`s t-test; blunt-ended bars, two-way ANOVA). PICD assay as shown in (B), but with addition of blocking antibodies ZB4 and αTNF-α (final concentration given below the chart) as indicated (C, n = 3; *p < 0.05, clamped bars, student`s t-test; blunt-ended bars, two-way ANOVA).