FIG. 2.

siRNA-mediated inhibition of HCV replication as measured by luciferase activity. (A) Effects of siRNA dose and sequence on luciferase activity. The indicated amounts of siRNA were transfected into 5-2 cells (5 × 10⁴ in a 24-well plate) with 1 μl of Oligofectamine (Invitrogen). After 48 h of incubation, cell lysates were subjected to a luciferase assay (BrightGlo; Promega). Luciferase activities were normalized to that obtained by a buffer transfection. The data shown are averages of three independent transfections ± the standard deviations. (B) Effect of siRNA on cell viability. Cell viability in culture was determined by measuring the level of ATP in cells 48 h after transfection (Cell Viability Luminescent Assay; Promega). ATP levels were plotted in arbitrary luminescence units.