FIG. 7.

Effect of E2₆₆₁ on cell aggregation. Daudi cells were treated with no MAb (A), 5A6 (anti-CD81) at 1 μg/ml (B), mock antigen (C), E2₆₆₁ antigen (5 μg/ml) (D), or E2₆₆₁ antigen complexed with MAb H53 (E) or with MAb 6/53 (F). Cells were monitored for aggregation by visual light microscopic inspection and FACS analysis. Daudi cells treated with 5A6 and E2 showed signs of aggregation, forming long cell-cell chains. Results were quantified by analyzing FSC/SSC profiles of the cells by FACS analysis, where the percentage of cells with high FSC/SSC profiles is shown in the upper quadrant of each plot.