FIG 4.

IFIT3 strengthens IFN-α effector signaling by promoting STAT2 phosphorylation. (A to D) HepG2 and HL-7702 cells with silenced or enhanced IFIT3 expression were seeded into 6-well plates overnight and then treated with IFN-α (1,000 IU/mL) for 30 min before being harvested. The levels of STAT2 and phosphorylated STAT2 (p-STAT2) were examined by Western blotting. GAPDH was used as an internal control. Western blot strips were quantified by densitometric analysis, and values in the bar graphs are shown as fold changes compared to the control. (E) HepG2 cells with enhanced IFIT3 expression were pretreated with ruxolitinib for 6 h before treatment with IFN-α (1,000 IU/mL) for 30 min. Cells were treated with dimethyl sulfoxide (DMSO), which served as a negative control. (F to I) HepG2 cells with enhanced IFIT3 expression were pretreated with ruxolitinib or DMSO for 6 h and then cultured with IFN-α (1,000 IU/mL) for 6 h. A control (without ruxolitinib or DMSO) was used for each treatment group. The experiments were performed in triplicate, and data are expressed as means ± SD.