FIG. 1.

Elimination of replicating N-Neo/C5B RNAs by IFN-α treatment. (A) Diagram of full-length dicistronic selectable HCV RNA. The HCV IRES drives expression of the neomycin resistance gene (Neo) as a selectable marker. Expression of the full-length HCV polyprotein is under control of the encephalomyocarditis virus (EMCV) IRES. (B) Huh7 cells harboring dicistronic full-length replicating HCV RNAs (NNeo/C5B, clones 2-3 and 3) were cultured in the presence or absence of 100 U of IFN-α2b (IFN)/ml for 2 weeks. The RNA status of the cells was determined by Northern blot with a probe specific for NS5B (top panel). 28S rRNA is shown as a loading control (bottom panel). Cells treated with IFN-α had no detectable HCV RNA. (C) Absence of HCV protein expression after IFN-α treatment was verified by immunoblot with antibodies specific for E2 and the core protein. An immunoblot of β-actin is shown as a loading control.