Binding of IgG-coated RBC to cells infected with gE CT domain mutants. HaCaT cells were infected with F-BAC, F-BACΔgE, gE-448, gE-470, gE-495, and gE-519 using 5 PFU/cell for 10 h. The cells were incubated with 51Cr-labeled, IgG-coated RBC for 2 h at 37°C and then washed, and total radioactivity bound to cells was determined. The amount of radioactivity bound by F-BAC-infected cells was arbitrarily set at 100, and triplicate wells infected with F-BACΔgE, gE-448, gE-470, gE-495, and gE-519 were compared to this value.