Fig. 1. A lineage of antibodies with cross-reactivity to H3N2 and H1N1 subtypes were identified.

a Schematic of isolation of influenza HA specific antibodies from an individual vaccinated with trivalent inactivated influenza vaccine. The isolated antibodies were tested for dose-dependent binding and neutralizing activities against group 2 HK/68 H3N2 and group 1 SC/09 H1N1 (b). 8D6, an unrelated HCV antibody was included as a negative control. The EC50 and IC50 values are shown into heatmap. n, not binding or not neutralizing. c Distribution of V gene families in heavy chains of all distinct clones (n = 19). d Summary of the germline (V-D-J for heavy chain and V-J for light chain) and HCDR3 of V_H3-48/V_K1-12 lineage antibodies.