Fig. 5

IL-21 enhances CD4⁺ and CD8⁺ T_SCM expansion. Naïve T cells from healthy donors (n = 3) were cultured for 10 days and fold expansion were analyzed in short costimulation (solid black line), long costimulation (solid grey line) short + IL-21 (black dashed line) and long + IL-21 (grey dashed line) conditions. a, b Absolute fold expansion of CD4⁺ (a) and CD8⁺ (b) (mean ± SEM), expressed in increment of cells from the starting culture time point is shown. c, d Absolute fold expansion of CD4⁺ (c) and CD8⁺ (d) total TSCM (TSCM + TSCM-like) (mean ± SEM). *p < 0.05; **p < 0.01; ***p < 0.001