FIG. 4.

Replication of F-BAC mutants. HaCaT cells were infected with F-BAC, F-BACΔgE, gE-448, gE-470, gE-495, or gE-519 using 5 PFU/cell for 2 h, and extracellular virus was then inactivated by washing the cells briefly with 0.1 M Na citrate, pH 3.0. At various times, the combined cells and medium (A) or medium alone (B) was harvested, frozen, and sonicated, and HSV-1 was titered on Vero cells by plaque titration. The standard deviations are shown as bars and can be seen in a few cases, but for most points, these bars are small and are covered by the symbols. WT, wild type.