Figure 4.

Replication kinetics of HSV UL21 deletion mutants. Monolayers of Vero cells were inoculated for 1 h at 37 °C with the indicated viruses at an MOI of 0.1, followed by brief treatment with low pH citrate buffer to inactivate virus that had not entered cells. At the indicated time points, cells and medium were harvested together, freeze/thawed twice, sonicated briefly, then centrifuged to remove cellular debris. Clarified supernatants were titrated by plaque assay on monolayers of L21 cells. Each data point represents the average of three independent infections for each virus, titrated in duplicate. Parental HSV strains are indicated with solid lines, and their corresponding UL21 deletion mutants are indicated with dashed or dotted lines. Error bars are standard error of the means.