Campylobacter jejuni Modulates Reactive Oxygen Species Production and NADPH Oxidase 1 Expression in Human Intestinal Epithelial Cells

Figure 7

The effect of NOX1 silencing on C. jejuni interaction, invasion, and intracellular survival. Caco-2 cells were transfected with NOX1 siRNA or scrambled siRNA (Scr siRNA). (a) qRT-PCR showing expression of NOX1 after siRNA transfection. (b) Western blotting showing expression of NOX1 after 72 hours of siRNA transfection. (c) Detection of extracellular ROS from Caco-2 cells after 72 hours of siRNA transfection followed by coincubation of C. jejuni for 3 hours. (d) After 72 hours of siRNA transfection followed by C. jejuni infection for 3 hours, Caco-2 cells were washed with PBS and lysed and the numbers of interacting bacteria were assessed or (e) for invasion assay, the cells were incubated with gentamicin (150 μg/ml) for 2 hours to kill extracellular bacteria and then lysed, and the numbers of intracellular bacteria were assessed. (f) For intracellular survival assay, 2 hours of gentamicin treatment was followed by further incubation with gentamicin (10 μg/ml) for 18 hours. Then, the cells were lysed, and the number of intracellular bacteria was determined. Experiments were repeated in three biological and three technical replicates. Asterisks denote a statistically significant difference (; ; ; ).

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