Figure 1.

Vaccination with modified vaccinia virus Ankara (MVA) expressing the hemagglutinin gene of influenza A(H5N1) virus A/Vietnam/1194/04 (rMVA-H5) induced a broadly reactive antibody response profile. A, Protein array analysis was used to determine titers against hemagglutinin subtype 1 (HA1) from 18 antigenically distinct H5 influenza A viruses in sera obtained at weeks 0, 4, 8, 52, 56, and 72 after vaccination. The seasonal influenza A viruses sH1N1 and sH3N2 were included as a control. Each column represents an individual serum sample (individual samples are ordered identically within each time point), and each row represents an antigen. The key indicates log₂-transformed titers from protein array analysis, with blue indicating a low titer and red indicating a high titer. B, Phylogenetic tree of influenza virus antigens used in this study based on the HA1 domain of the HA gene. The maximum-likelihood tree was constructed using the best-fit model (HKY+G) in MEGA 6.06 and visualized in FigTree, version 1.3.1 (available at: http://tree.bio.ed.ac.uk/software/figtree). Bootstrap values were calculated from 1000 replicates; only values >0.6 are shown. Values indicate numbers of nucleotide substitutions per site. Red indicates the homologous virus strain, and blue indicates viruses used in follow-up experiments.