FIGURE 8.
OspZ mediated inhibition of NF-κB activation and IL-8 production during Shigella infection. A, -fold increase in NF-κB-dependent luciferase activity in HeLa cells transfected with pEGFP-C2, pEGFP-NleE, pEGFP-NleE49AAAA52, pEGFP-OspZ, or pEGFP-OspZ49AAAA52 and left unstimulated or stimulated with TNF for 8 h where indicated. Results are the mean ± S.E. (error bars) of three independent experiments carried out in duplicate. *, p < 0.05, unpaired two-tailed t test. B, reverse transcription-quantitative PCR analysis of IL8 expression in HT-29 cells 1 h after infection. Results are expressed as mRNA expression levels that were normalized relative to 18S and are the mean ± S.E. (error bars) of three independent experiments carried out in duplicate. *, significantly different from uninfected HT-29 cells or HT-29 cells infected with wild type S. flexneri 6 or ΔospZ (pOspZ) (p < 0.05, unpaired two-tailed t test). C, IL-8 production from HT-29 cells infected with derivatives of S. flexneri 6 as indicated for 2 h and left unstimulated or stimulated with TNF for 2 h. Results are the mean ± S.E. (error bars) of three independent experiments carried out in duplicate. *, p < 0.05, unpaired two-tailed t test.