Fig. 3
Kinetics of antibody affinity maturation following human vaccination. a–j Sequential SPR analysis of human vaccine sera (pre- and post- vaccination) was performed against properly folded homologous H1N1pdm09 HA0 (a, f), HA1 (b, g), and HA2 (c, h) domains, and H3 HA1 (d, i) and B-HA1 (e, j). Samples from 16 individuals (Table 2) that received repeat vaccination in both year 1 and year 2 (Fig. 4) are not included in the Fig. 3 dataset. Ten-fold, 50- and/or 250-fold diluted individual serum from each participant in the vaccine study at pre-vaccination (D0) and at 28 days or 180 days after immunization (D28, D180) are evaluated as shown for FluBlok (in blue), FluCelvax (in red), and Fluzone (in green) for subjects recruited in the first year (2015–2016; a–e) and second year (2016–2017; D0 and D28; f–j). Serum antibody off-rate constants are determined as described in Methods. Slower dissociation kinetics (off-rate) of antigen–antibody complex means higher antibody affinity. For Day 28 post-vaccination off-rate constants, and fold change from Day 0, an ANCOVA model was used for comparison between the vaccine groups, adjusted for gender, age, and baseline (Day 0) values (Supplementary Tables 6 and 7). Statistically significant differences between groups and pairs are indicated by horizontal bars. Source data are provided as a Source Data file
