FIG 4.

Cell surface expression of wild-type and mutant gH/gL complexes. ARPE-19 epithelial cells expressing wild-type or mutant gH/gL complexes were analyzed for surface expression by CELISA using anti-gH MAb AP86. Shown are the numbers of relative light units (RLU) for individual gH mutants (A), individual gL mutants (B), and representative combinations (C). Black and white bars, mutants that tested positive and negative for cell-cell fusion, respectively; horizontal dashed lines, the threshold for surface expression, as defined by the surface detection of gH expressed without gL. Experiments were performed in triplicate, and error bars represent standard errors.