Statistical analyses
Statistical analyses were performed using the GraphPad Prism software, version 9.3.1. Antibody titers between the groups were compared with two-tailed Mann–Whitney U test and significance is indicated as *p < 0.05; **p < 0.01; ***p < 0.001. If there is no significant difference, it is not depicted in the figure. Correlations between the viral load (1/Ct) value of the viral RNA and antibody levels in each compartment are represented using Heatmaps. Heatmaps depicting the magnitude and statistical significance between the 1/Ct value of viral RNA and antibody (IgG, IgA) were analyzed with a two-tailed Spearman test. Each box represents an antigen-specific antibody response. Color indicates correlation coefficient magnitude and direction. Positive correlation of the viral load (1/Ct) values with antibody feature is indicated in blue and negative correlation in red.