Fig. 2: Biological stability and immunological migration characteristics of RBD-GP96-Fusion as a dominant vaccine.
A Representative BIAcore diagrams of RBD and RBD-GP96-Fusion bound to hACE2 protein (baculovirus expression). The KD value was calculated using the software BIAevaluation Version 4.1 (GE Healthcare). The values shown are mean ± SD of two independent experiments. B The complex structure of hACE2 (PDB: 1R42) is docked onto RBD-GP96-Fusion dimer by ZDOCK, showing the complete exposure of dual RBMs. Two RBD protomers are shown as surface and colored in hot pink and cyan, respectively. Two hACE2 proteins are shown as cartoon and colored in yellow. C The difference in thermal aggregation degree between RBD, GP96 and RBD-GP96-Fusion proteins was analyzed using the PR.NT.48 instrument. D The SDS-PAGE migration profiles of RBD, GP96 and RBD-GP96-Fusion hydrolyzed by trypsin at different pH were analyzed to determine the difference in anti-enzymatic ability. E Representative in vivo fluorescein image of 6- to 8-week-old female BALB/c mice on days 0, 7, and 30 after dorsal vaccination with RBD (with aluminum hydroxide adjuvant), GP96 and RBD-GP96-Fusion vaccines. In (C, E), n = 3 samples per group were analyzed. The data are representative of two independent experiments with similar results. Geometric mean ± geometric SD are shown. One-way ANOVA with Bonferroni correction or unpaired two-tailed t tests were conducted according to the distribution of the data. ns p å 0.05, *p ≤ 0.05, ****p ≤ 0.0001.
