FIG 5.

Activity of selected MAbs in HI and PRNAs. HA-reactive antibodies were tested in an HI assay against JD13 H10N8 (A), H10N7 virus (A/mallard/Interior Alaska/10BM01929/10) (B), and an H3N8 virus (A/Northern shoveler/Alaska/7MP1708/07) (C). MAbs 1B10 and 2F10 showed HI activity against H10N8 and H10N7 viruses but lacked reactivity to H3N8. Stalk-reactive MAb 9H10 showed no HI activity against the tested viruses. (D) A PRNA with anti-H10 head antibodies 1B10 (anti-head), 2E11 (anti-NA) and 9H10 (anti-stalk) was performed. Both anti-head and anti-stalk antibodies were effective in reducing the number of plaques, with the anti-head antibody 1B10 displaying 320 times greater potency than that of the anti-stalk MAb 9H10. Anti-NA antibody 2E11 was not able to reduce plaque numbers at any tested concentration. (E) Reduction of plaque size (as measured by plaque diameter) by the three tested MAbs. Using this readout, the anti-NA antibody 2E11 displays robust reactivity.