Enhancing vaccine half-life as a novel strategy for improving immune response durability of subunit vaccines
Fig 5
The RBD-sFc-HR/trimer vaccine elicited a robust T-cell response in vivo.
(A) The number of RBD-specific IL-4-producing memory T cells in the spleen was analyzed by flow cytometry after stimulation with the SARS-CoV-2 spike RBD peptide pool for three d. Memory T cells were gated on CD3+CD4+CD44+ (left) or CD3+CD8+CD44+ (right) populations. (B) The percentage of central memory (CD44+CD62L+) CD4+ or CD8+ T cells in the spleen. (C) The percentage of effector memory (CD44+CD62L-) CD4+ or CD8+ T cells in the spleen. n = 5 mice in each group in A-C. Spleen samples were obtained from the mice at 14 d after the third immunization. The data are presented as the means ± SEMs. P values were determined via one-way ANOVA. A p value < 0.05 was considered statistically significant (*P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001).