Neutralizing activity of anti-gp120 antibodies is not affected by HNP-1.

Varied concentrations of neutralizing antibodies against distinct domains of HIV-1 gp120, PG9 (A), and m36 (B), were added to TZM-bl cells decorated with HXB2 (triangles) or BaL (circles) pseudoviruses immediately prior to raising the temperature to 37°C for 90 min. Experiments were performed either in absence (black symbols) or in the presence (red symbols) of 7.3 µM HNP-1 in HBSS supplemented with 10% human serum. Virus-cell fusion was measured by the BlaM assay. Data points are means and SEM from a representative triplicate experiment (PG9) or form two duplicate experiments (m36). Solid curves are obtained by non-linear curve fit to F = 100/(1+[X]/IC50), where [X] is the concentration of an inhibitor or an antibody. See Table 2 for the respective IC50 values. The experimental points showing no detectable reduction in the fusion signal were fitted with a straight line.