Immunostaining of HCV NS3 and Western blot of HCV NS5B proteins. (A) The antiviral activity of the IRF9-Stat fusion constructs in R15-3 cells containing HCV 1b sub-genomic RNA HCV. At 48 hours post-transfection the cells were mounted onto a glass slide, stained for HCV NS3 protein and counterstained with hematoxylin. Panel i and ii: Huh-7 cells (-) and (+) IFN-α (1,000 IU/ml). Panel iii and iv: R15-3 cells (-) and (+) IFN-α. Panel v: IRF9 transfected R15-3 cells Panel vi: IRF9-S1C transfected R15-3 cells Panel vii: IRF9-S2C transfected R15-3 cells Panel viii: IRF9-S1C plus IRF9-S2C transfected R15-3 cells. (B) Upper panel: HCV NS5B expression levels in R15-3 transfected cells at 72 hours post-transfection. Lower panel: Shows β-actin protein expression levels using equal amounts of protein lysate.