Fig. 4: OligoD insertion into HA enhances neutralizing antibody responses.
a, Insertion of oligoD (12D) at the C-terminus of H1 HA (Protein Data Bank ID: 1RU7 for reference). b, BLI binding analysis of H1 HA or H1 HA-12D with HA-specific mAbs. c, A prime-boost immunization study with H1 HA or H1 HA-12D adjuvanted with alum via subcutaneous injection in BALB/c mice. d, Serum H1 HA-specific IgG titers over time (n = 10 mice per group). Antibody titers of week 8 and week 14 from the two groups are plotted on the right for comparison (each circle represents a single mouse). e, Serum NT50 against authentic H1N1 A/NC/20/99 viruses over time (n = 10 mice per group). NT50 at weeks 8 and 14 are plotted on the right for comparison (each circle represents a single mouse). f, Serum binding titers to H1 HA in the presence of competing mAbs. Each circle represents a single mouse. Fold change is indicated by arrows with numbers. Dashed lines indicate the limit of quantification in d–f. Arrows in d,e indicate prime and boost immunizations. Data are presented as geometric mean ± s.d. of the log10‐transformed values. Comparison of IgG titers (d) or NT50 (e) over time was performed using two-way ANOVA followed by a Bonferroni test. Comparison of two groups was performed using the two-tailed Mann–Whitney U-test (d,e). Comparison of multiple groups was performed using one-way ANOVA followed by a Bonferroni test (f). P values of 0.05 or less were considered significant.
