Fig. 4: Stability and long-term efficacy of the NiV G nanoparticle vaccine.

a The immunization schedule diagram. The NiV G-ferritin was first emulsified with an aluminum adjuvant and then stored at 4 °C, 27 °C, and 37 °C for 7 or 14 days, respectively. 6–8 weeks old mice were immunized with the above prepared NiV G-ferritin immunogens (corresponding to 10 μg NiV sG), and sera were collected at Days 21, 42, 60, 132, and 222 following first immunization for humoral immune response analysis. NiV G-ferritin vaccine stored at 27 °C for 1 h and ferritin alone were included as the positive or negative controls. b–f Serum neutralization titers against NiV-M pseudovirus and NT₅₀ values are determined. Dashed lines indicate the limit of detection (LOD) of the assays. g Kinetics of NT₅₀ titers after immunization with NiV G nanoparticle vaccine. Two independent experiments were performed in duplicate, and representative data are shown. Data from each group are shown as geometric mean with geometric SD. Statistical significance was determined by the one-way ANOVA with Dunnett’s multiple comparisons test, compared with 27 °C 1 h group in b–f. ns not significant, p > 0.05.