Figure 3.

Binding between factor H or VCP with H1N1 (A), and H3N2 (B) IAV subtypes were determined via ELISA. Microtiter wells were coated with various concentrations of factor H, VCP or VSV-G (0.625, 1.25, 2.5, and 5 μg/well) in carbonate bicarbonate buffer, pH 9.6 overnight at 4°C. H1N1 or H3N2 virus (1.36 × 10⁶ pfu/ml) was added to each well in the presence of 5 mM CaCl₂ and probed with either monoclonal anti-influenza virus H1 or polyclonal anti-influenza virus H3 antibody. VSV-G pseudotyped particles were used as a negative RNA virus control. The data were expressed as mean of three independent experiments done in triplicates ± SEM.