Fig. 4
Immunogenicity of CN-1 and CND-1 proteins, in Balb/C mice, administered by intranasal (in) route. Six- to eight-week-old mice were immunized with three doses of each formulation: Group 1: CN-1, Group 2: CND-1, Group 3: PBS. Twenty-seven days after the third immunization, mice were sacrificed. Antibody responses in the serum and bronchoalveolar lavage fluid (BALF) as well as CMI in spleen, were evaluated. a Diagram of immunization. Humoral immune response measured by ELISA, anti-N protein from SARS-CoV-2, b IgG in sera, c IgA in BALF; anti-HBcAg d IgG in sera and e IgA in BALFs. Data of IgG are represented as log10 of the titers. Data from IgA are expressed as O.D492nm. f Frequency of IFN-γ secreting cells, by ELISpot, in splenocytes after in vitro stimulation with the conserved peptide N351–365. Graph shows the response of individual mice. In all graphics the horizontal bar represents the mean value of the group. The statistical analysis was done by One-Way Anova followed of Tukey’s multiple comparison test. **p < 0.01, ***p < 0.001