FIG. 5.

Antiviral effect of the syndecan-Fc hybrid molecule before, during, or after virus exposure. (A) Syndecan-1-Fc or control Fc (5 μg/ml) was added to TZM-bl cells 1, 2, or 4 h before (negative values on the y axis) or after (positive values on the y axis) the addition of HIV-1 (R5 JR-CSF) (1 ng of p24) or together (time zero) with the virus. Infection was measured 48 h after infection as β-galactosidase activity. (B) Activated PBMCs (200,000 cells) were infected with JR-CSF (500 pg of p24) for 3 days, washed three times to remove cell-free virus, and added to TZM-bl cells in the presence of increasing concentrations of syndecan-1-Fc or control Fc (0.1 to 100 μg/ml) diluted in a pool (n = 6) of seminal plasma. Infection was scored as above. The points are median values, and error bars represent standard errors of triplicates. The P values were calculated using a one-sided t test assuming equal variances.