Fig 3.

Neutralization activity assessment of IAVs and an IBV for anti-M1 and anti-NP mAbs. Neutralization of A/Netherlands/602/2009 (H1N1) (A), A/Hong Kong/4801/2014 (H3N2) (B), and B/Colorado/06/2017 (C) strains measured in microneutralization assays. The minimum neutralization concentration in micrograms per milliliter of the respective mAb is displayed and was established via a hemagglutination-based readout. The minimum neutralizing concentration represents the lowest antibody concentration at which no hemagglutination was detected. The data are presented as individual technical replicates of a single experiment, and the linear regression for each mAb group is represented. The dashed vertical gray line represents the assay detection limit (100 µg/mL). mAbs that did not reach this limit were assigned a value of 200 µg/mL. CR9114, which has known neutralizing activity against H1N1 and H3N2 viruses, or 2E01, which has known neutralizing activity against influenza B viruses, and a CHIKV E1 virus mAb, 1D04, were used as positive and negative controls for all experiments, respectively. P values indicate the statistical significance of the difference between the groups and the irrelevant antibody control assessed by one-way analysis of variance (ANOVA) followed by a multiple-comparison test. Only P values lower than 0.05 are presented.