Figure 5.

The EtxB-Pol fusion protein inhibits HSV-1 replication and DNA synthesis in Vero cells. (A) Inhibition of plaque formation. Confluent Vero cells were infected with HSV-1 at a moi of 0.001 and treated with EtxB-Pol (●), EtxB (▴), or the Pol peptide (■) for 48 hr. The plaque-forming efficiency was calculated as a percentage of plaques compared with an untreated control. The graph shows the mean values and SDs from three independent experiments. (B) Inhibition of virus yield. Vero cells were infected with HSV-1 at different mois and treated with various amounts of EtxB-Pol for 48 hr. Virus progeny was harvested from the infected cells and titered by using a standard plaque assay. (C) Inhibition of viral DNA synthesis. Total DNA was extracted from Vero cells infected with HSV-1 and treated with EtxB-Pol or EtxB or cells that were infected and untreated (HSV-1) or not infected (mock). Samples were digested with BamHI, blotted, and hybridized to a probe complementary to the HSV-1 BamHI Q fragment. Plotted values represent the number of viral genomes relative to autoradiographic bands, quantified by densitometry and correlated with a reference curve as described in the text.