FIG. 3.

Cellular binding of HCV-LPs and recombinant envelope glycoprotein requires N sulfation of cell surface HS. Sucrose gradient-purified HCV-LPs (A) and recombinant E2 (B) and E1 (C) proteins were incubated with chemically modified heparins (10 μg/ml) for 30 min at room temperature. Envelope protein-GAG complexes were added to human hepatoma cells for 1 h at 4°C, and cellular binding of HCV-LPs and recombinant proteins was quantified by flow cytometry as described for Fig. 2A. Data are shown as percent binding of ligands (mean ± standard deviation [SD] of a representative experiment performed in triplicate) relative to binding of ligands in the absence of modified heparins (100%). De-2-O- and de-6-O-sulfated heparin (SH) lacks O-sulfo groups at position 2 or 6; de-N-SH lacks N-sulfo groups.