Fig. 2.

Adolescents have boosted CD8⁺ T cell responses to the WT virus after the third dose of the BNT162b2 vaccine. a Longitudinal analysis of S-specific interferon-γ (IFN-γ)⁺ CD4⁺, interleukin-2 (IL-2)⁺ CD4⁺, IFN-γ⁺ CD8⁺, and IL-2⁺ CD8⁺ T cells responses in evaluable adolescents (pre-dose 1 N = 18, post-dose 2 N = 18, pre-dose 3 N = 21, post-dose 3 N = 19). A third dose booster increased the S-specific IFN-γ⁺ CD8⁺ and IL-2⁺ CD8⁺ T cell responses, while IL-2⁺ CD8⁺ T cell responses were higher post-dose 3 compared to post-dose 2. Longitudinal analysis was determined using paired t-test after natural logarithmic transformation with p values denoted. Dots representing the same participants are linked by a straight line. Data labels and centre lines show geometric means (GM) estimates, with corresponding 95% confidence intervals shown by error bars. b Non-inferiority test of S-specific IFN-γ⁺ CD4⁺ (adolescent N = 26, adult N = 28), IL-2⁺ CD4⁺ (adolescent N = 26, adult N = 28), IFN-γ⁺ CD8⁺ (adolescent N = 26, adult N = 28) and IL-2⁺ CD8⁺ (adolescent N = 26, adult N = 28) T cell responses in evaluable adolescents in comparison to adults. Geometric mean ratios (GMR) and two-tailed 95% confidence intervals (CI) were plotted. S-specific IFN-γ⁺ CD8⁺ and S-specific IL-2⁺ CD8⁺ T cell responses were non-inferior, while S-specific IFN-γ⁺ CD4⁺ and S-specific IL-2⁺ CD4⁺ T cell responses were non-conclusive. Geometric mean ratios and their associated two-sided 95% confidence intervals (CIs) were plotted. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. ns not significant. Cut-offs were drawn as grey lines. WT wild-type