FIGURE 4.

Expression of Ifng, Tnfa, Il-1b, Il-6, Il-10, and Il-12b mRNAs in murine intestinal ICE-1 cells following 1 h (A) and 4 h (B) infection with MOI 1:100 of wild-type S. Enteritidis (light gray bars) and S. Enteritidis fimH::kan mutant strain (dark gray bars). Real-time RT-PCR was used to analyze expression of cytokine mRNAs. Cytokine levels were normalized against Actb. Non-infected ICE-1 cells were assigned as a calibrator sample, and fold change was measured over unstimulated cells set at 1. The comparative Ct method was used for relative quantification of gene expression. Data represent the mean ± SD of four independent experiments. Triplicate samples were analyzed in each experiment to confirm accuracy and reproducibility of quantitative real-time PCR (qPCR). Values marked with ^∗ differ significantly (P < 0.05).