Fig. 3.

High levels of virus-specific CD4⁺ T cell at early convalescent phase correlate with long-term maintenance neutralizing antibodies. Antibodies present in plasma of the high- (n = 23) and low-CD4⁺ groups (n = 23) against RBD and N, and nAbs in the plasma at M2 and M12, were examined using ELISA and FRNT₅₀ assays. a, b Pair comparisons of IgG levels against RBD and N and nAbs between M2 and M12 for the high-and low-CD4 + groups; b Pair comparisons of IgG levels against the 13G2 and 08B3 clusters. Percentages on top of dot plots represent frequencies of samples with antibody titers above the cutoff. Each dot represents an individual participant. **p < 0.01 and ****p < 0.0001. Student’s t-test was used to analyze differences in the mean values between groups. The Mann–Whitney test was used to compare the central tendencies of the two groups (mean or median). Wilcoxon rank-sum test was used to compare paired continuous variables that were not normally distributed. The percentage above the dot plots indicates the detection rate of each group.