Dengue Virus Infection Causes the Activation of Distinct NF-κB Pathways for Inducible Nitric Oxide Synthase and TNF-α Expression in RAW264.7 Cells

Figure 4

ROS is independent of NF-κB activation followed by TNF-α and iNOS expression during DENV infection. (a) CM-H₂DCFDA-based staining followed by flow cytometric analysis determined ROS generation in RAW264.7 cells infected with DENV 2 at the indicated time points. The mean fluorescence intensity (MFI) of each stain is shown as the mean ± SD of three individual experiments. ns: not significant. In the presence of the ROS-scavenger NAC, NF-κB reporter assay (b), ELISA (c), Griess reagent (d), and western blot analysis (e) quantified the activation of NF-κB and the expression of TNF-α and iNOS/NO in DENV 2-infected cells. DMSO was used for the negative control. and , compared with untreated cells. , compared with DENV. ns: not significant. For western blot results, one set of representative data obtained from three independent experiments is shown. The relative ratio to β-actin based on densitometer quantification and analysis using ImageJ software is shown. For all experiments, the quantitative data shown represent the mean ± SD values of three independent experiments.

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