FIG. 5.

Incubation of target cells with SU-Fc inhibits infection by virus pseudotyped with HTLV-1 envelope. HeLa cells were incubated in the absence of envelope proteins (Control) or in the presence of SU-Fc (SU-Fc), HIV-1 gp120 (gp120), or pooled and purified human IgG (IgG) at the concentrations indicated. Subsequently, the target cells were infected with luciferase-transducing cell-free HIV-1 stocks pseudotyped with HTLV-1 envelope (A) or VSV-G protein (B). The cells were incubated for 24 h, and luciferase activity was determined. Results represent means and standard deviations from three independent assays.