Fig. 4: The CCD/RBD-HR vaccine targets dendritic cells.

a Immune cell recruitment in the CLN 72 h after intranasal immunization with PBS, RBD-HR, or CCD/RBD-HR was determined with FCM. b RBD-HR uptake after incubating mouse BMDCs with or without CCD for 30 min. c Maturation of DCs in the CLN 72 h after intranasal immunization with PBS, RBD-HR, or CCD/RBD-HR as determined by the expression of CD40, CD80, CD86, and MHC II. d, e BMDCs were treated with PBS, RBD-HR, or CCD/RBD-HR for 24 h. d Maturation of BMDCs was determined by the expression of CD40 and CD80 with FCM. e Magnetic Luminex assay test of cytokines in the supernatant. The proliferation (f) and fractions of CD69⁺ (g) and CD44⁺ (h) of both CD4⁺ and CD8⁺ T cells were determined with FCM after T cells were co-incubated with pre-stimulated DCs for 48 h. (i) Cytokines (IL-4 and IFN-γ) in the supernatant were determined by ELISA. Data were displayed with floating bars in (a–d) and (f–i). The middle line indicates the median and the box shows the data range. Data were presented as mean values ± SEM. n = 5 mice per group in a and c. Three independent experiments (n = 3) were performed in each group in (b, d–i). P values were calculated with One-way ANOVA followed by Dunnett’s multiple comparisons tests. Source data are provided as a Source Data file.