Figure 10

The suppression of ERK but not NF-kB signaling by small chemical inhibitors contributes to HSV-1 replication. (a–e) Effect of NF-κB inhibitor (BAY11-7082), ERK inhibitor (PD98059) and EGF on HSV-1 multiplication. Vero cells were infected with HSV-1 at 100 PFU for 30 min, and cultured with DMSO (a–d) or sterile water (e), 1 μM BAY11-7082 (a,b), 10 μM PD98059 (c,d) or 0.1–100 ng/ml EGF (e) for 48 hours, followed by plaque analysis. (a,c,e) and (b,d) display the total number of plaques and the number of the plaques with a diameter of over 0.75 mm, respectively. The number of plaques of untreated cells was defined as 100%. The number of plaques of DMSO or sterile water treated cells was defined as 100%. (f) Effect of PD98059 on HSV-1 proliferation in human HepG2 cells. HepG2 cells were infected with HSV-1 at an MOI of 1 for 30 min and subsequently cultured with DMSO or 10 μM PD98059 for 20 hours. Infected cells were harvested, and genomic DNA containing viral DNA was isolated and measured by real-time PCR. (a–f) Standard deviations were determined by analyzing the data from three experiments. ^*P < 0.05, ^**P < 0.01 and ^***P < 0.001 indicate the statistical significance compared with vehicle (DMSO) treated cells, and N.S. indicates not significant.