Figure 1. Characterization of 17 neutralizing monoclonal antibodies (mAbs).

The antibodies are arranged in the order of neutralization potency (column 9) with the most potent antibodies at the top. Seventeen mAbs isolated by human B cell hybridoma generation exhibited neutralization potential (shown as half-maximal inhibitory concentration [IC₅₀]) at <5 μg/ml against the H3N2v virus by microneutralization assay. Nine antibodies exhibited hemagglutinin inhibition (HAI) activity, indicating that they disrupt receptor-binding function of the virus. The mAbs were tested for binding against HA from H3N2v or 3 seasonal strains (shown as half-maximal effective concentration [EC₅₀]). The > symbol indicates that binding was not detected at the maximum concentration tested (2 μg/ml). The experiments for determining EC₅₀ (n = 4), IC₅₀ (n = 3), and HAI (n = 3) were conducted twice independently.