FIG. 8.
Single-step growth analysis of HSV-1(F) and two HSV US3-null mutant viruses on HEp-2 cells. Replicate cultures of HEp-2 cells were infected with HSV-1(F) or either of two US3-null mutant viruses (R7037 and R7039). At the indicated times, cells were harvested and viral yield was determined by titration on Vero cells. Virus yield is expressed as PFU per milliliter of culture medium. Each datum point represents the mean of three independent experiments, and the error bars indicate the sample standard deviation.