Figure 6

FFA treatment of S3-GFP replicon cell culture blocks IFN-α induced Jak-Stat signaling. (A) Western blot analysis of Jak-Stat signaling proteins were done in S3-GFP cells cultured with different concentration of FFA for 24 h and then treated with 1000 IU/mL IFN-α for 30 minutes. β-actin levels were used as loading controls. (B) FFA treatment blocks IFN-α-induced ISRE-firefly luciferase activity. S3-GFP cells were transfected with 1 μg of pISRE-luciferase plasmid and then cultured with FFA for 24 h. Cells were then treated with 1000 IU/mL IFN-α. 24 h post-transfection, IFN-β promoter activity in the presence and absence of FFA treatment was measured. *P < 0.05 (1 tail), Student t test. (C) Flow cytometric analysis of IFNAR1 expression in Huh-7 cells treated with or without FFA. The left panel shows a histogram of IFNAR1 expression with FFA (0.5 mM) treatment for 24 h shifted to the left (red line). The right panel shows the mean fluorescence intensity (MFI) of the IFNAR1 signal. The flow cytometry plot is representative of three separate experiments, while the MFI values shown are an average (±SD) of these experiments.