Fig. 4: Functional characterization of antibodies against B/Colorado/06/2017 (V) and B/Phuket/3073/2013 (Y).

Mice were vaccinated and sera were collected as described in Fig. 2. Functional characterization of antibodies in the prime-only and prime-boost sera of mice vaccinated with mRNA-LNPs was performed in microneutralization (MNT) (n = 5) (p-values left to right <0.0001, 0.0047, <0.0001, 0.0011, <0.0001, 0.0154) (a), NAI (n = 3) (b), or ADCC reporter (n = 5) (p < 0.0001 for all comparisons) (c) assay against B/Colorado/06/2017 (V) influenza virus. Functional characterization of antibodies in the prime-only and prime-boost sera of mice vaccinated with mRNA-LNPs was performed in MNT (n = 5) (p-values left to right <0.0001, <0.0001, <0.0001, <0.0001) (d), NAI (n = 3) (e), or ADCC reporter (n = 5) (p-values left to right 0.0059, 0.0006, <0.0001, <0.0001, 0.0017, 0.0002, <0.0001, 0.0001) (f) assay against B/Phuket/3073/2013 (Y) influenza virus. In b and e, solid lines show NAI values obtained from prime-only sera, dashed lines show NAI values obtained from prime-boost sera. Sera from 3 to 5 randomly selected animals from each vaccination group was assessed in each assay. For a, c, and f the dotted lines indicate the limit of detection. For a, c, d and f, significance was assessed using a one-way ANOVA and groups were compared to the luciferase control group at the prime-only or prime-boost time point. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. For a, c, d and f, bars represent the group mean and error bars represent SD. Each symbol represents an individual animal. For b and e, data are presented as group mean at each sera dilution and error bars represent SD. Source data are provided as a source data file.