HSV-1 plaque assay

HSV-1 plaque assays were performed in triplicates for each biological sample. 1.5×10⁵ Vero cells were seeded in a 12-well plate in the complete DMEM and infected the following day with various dilutions of HSV stocks or culture supernatants. Two hours after infection, cells were overlaid with 1% agarose (Sangon) solution. After incubation for 3 days, cells were fixed with 4% formaldehyde and stained using 1% crystal violet solution at room temperature for 2 hours. After 3 washes with PBS, plates were allowed to dry and the numbers of plaques were counted. Viral titers were calculated as PFU/mL.