FIG. 2.
Coreceptor function of non-N-linked glycosylated CXCR4 mutants in cell fusion assays with R5 HIV-1 Envs. U373 target cells were transfected with a plasmid encoding the wild-type or a mutant coreceptor linked to the vaccinia virus promoter and infected with vCB21R-LacZ and vCB-3 (CD4). HeLa effector cells were infected with a vaccinia virus encoding an HIV-1 Env and with a vaccinia virus encoding T7 polymerase (vTF1-1). Cell mixtures (duplicates) were incubated at 37°C for 2.5 h. Fusion was assessed by measurement of β-Gal in detergent lysates of cells. The rates of β-Gal activity shown were obtained from separate samples in the same experiment. Error bars indicate the standard deviations of the mean values obtained from duplicate fusion assays. This experiment was performed three times, and the data from a representative experiment are shown in the figure. Abs570nm, absorbance at 570 nm.