Figure 4.

Comparison of killing effect of permissive tumor cells by Synco-2D and Synco-B18R in the presence of interferon. (a) SW480 and (b) HuH7 cells seeded in 24-well plates were infected with either Synco-2D (open bars) or Synco-B18R (closed bars) at 0.1 pfu/cell and cultured in medium without or with the indicated amounts of IFN-α. One well was mock-infected as a control. Cells were harvested 24 hours later and cell viability determined by trypan blue staining. The percentage of cell killing was calculated by the formula: % cell killing = (1 − (viable cell number in infected well)/(viable cell number in control well)) × 100. ^†P < 0.05, ^*P < 0.01 as compared with Synco-2D. IFN, interferon; pfu, plaque-forming unit.