Fig 6.

Effects of the gH:KV mutations on cell-cell fusion. (A) B78H1 cells were cotransfected with plasmids for the indicated glycoproteins, Giemsa staining was performed at 72 h posttransfection, and syncytia were counted. The gH plasmids containing either of the KV mutations alone are indicated as K (for N753K) and V (for A778V). Shown are the averages ± the SEM of data from two experiments performed in triplicate. (B) Representative images of syncytium formation by B78H1 (upper panels) and B78/C (lower panels) cells after cotransfection of different combinations of expression plasmids for wild-type gD, gB, and gL, indicated at the top, with plasmids expressing gH:wt or gH:KV, as indicated at the left. Giemsa-stained cells were photographed at either 20 h posttransfection (B78/C, first column) or 72 h posttransfection (all other panels).