Yield of cell-associated and extracellular virions complemented with gBΔ867, wt gB, or EGFR. The ΔgB HSV KΔt (9) was grown in 293T cells transiently expressing wt gB, gBΔ867, or EGFR as a negative control. At 24 h after infection, the cell-associated progeny virus (A) or virus released in the extracellular medium (B) was titrated in gB-complementing D6 cells.