Fig. 2: mutI-tri-RBD and homo-tri-RBD elicited similarly high levels of the immune response against the SARS-CoV-2 prototype strain in mice.
From: Design of a mutation-integrated trimeric RBD with broad protection against SARS-CoV-2
The mice were immunized with two-shot or three-shot injections, and for each shot, three different doses were used, including low (0.125 µg/dose), middle (0.5 µg/dose), and high (2.0 µg/dose) doses, respectively. a The timeline of vaccine immunization and serum collection. The levels of specific IgG elicited by mutI-tri-RBD in the sera collected on day 7 post-immunization (D28 in a), were detected with ELISA by using monomeric RBD of prototype SARS-CoV-2 strain, and the titers of neutralizing antibodies against the prototype strain were assessed by using the pseudo- and live virus neutralization assays. b, d, f An obvious dose-dependent response of the RBD-specific IgG (b) as well as pseudo-virus (d) and live-virus (f) neutralizing antibodies induced by mutI-tri-RBD were observed. c, e, g The RBD-specific IgG level (c), and the neutralizing antibody titers against the pseudo (e) and live (g) viruses elicited by mutI-tri-RBD were similar to those elicited by homo-tri-RBD. Data are presented as means ± SEM. P values were calculated by using one-way ANOVA followed by Sidak’s multiple comparison test. *P < 0.05, **P < 0.01, ns, not significant.
