Fig. 3: Specificity of serum neutralizing activity elicited by H1 stem nanoparticle variants.

a Serum pseudovirus-neutralization activity in the presence of competitor proteins. Immune sera were pre-incubated with either NC99 WT HA, HA gN38, or irrelevant RSV F proteins prior to evaluation of SG86 (H1N1) pseudovirus neutralization. Serum neutralization IC50 titers were calculated in the absence or presence of competitor proteins. b Percent inhibition of virus neutralization was calculated for each competitor protein. Dotted lines indicate the lower detection limit of the assay. Data are presented as scattered dot plots with horizontal lines indicating geometric mean for each group. Statistical analysis was carried out by using nonparametric Kruskal–Wallis test with Dunn’s multiple comparisons. Displayed results are representative of two independent experiments. Source data are provided as Source Data file.