Fig. 8

Immunization scheme of BALB/c mice with RBD-P and RBD (A). Analysis of antigen recognition with polyclonal antibodies of murine serum immunized with recombinant RBD and RBD-P orally (B) and intramuscularly (C). The Y axis shows the absorbance value measured at 450 nm Serum was placed at a dilution 1:200 for intramuscularly groups, and at a dilution 1:100 for orally groups. In boxplots, each data point is the mean of two wells per mouse serum. Also, each boxplot presents the mean as an X, the median as the middle line, the interquartile range as box limits, and the 2.5th and 97.5th percentiles as the whiskers. For all variables with the same letter, the difference between the means is not statistically significant. If two variables have different letters, they are significantly different (p < 0.05). The immunization scheme was prepared using Biorender