FIG 3.

Potency and breadth of immune response elicited by divergent HA-ferritin nanoparticles. Shown are hemagglutination inhibition (HAI) titers (log₂) of sera from mice 6 weeks after immunization with the indicated HA-Np vaccine against a panel of divergent H1N1 influenza viruses. Mice (n = 5) were immunized with HA-Nps at weeks 0 and 3 with either SAS adjuvant (A to F) or AF03 adjuvant (G and H). SAS and AF03 adjuvants were found to induce equivalent responses to all HA-ferritin nanoparticles tested (Fig. 5A). The x axis indicates the panel of H1N1 influenza virus strains tested by reference year, from 1934 to 2013 (Table 1). Dashed lines mark the limit of detection (3.32). Horizontal gray bars mark the 1:40 to 1:80 ranges as a visual aid. Red asterisks indicate matched strains.