IL-15 allows the induction of IL-2-producing SIV-specific CD4⁺ T cells under ART but does not improve antigen-specific CD8⁺ T-cell function. (A) Representative example of the expression of IFN-γ, IL-2, and TNF-a in response to Gag peptide pool at d−7 and at d46 after therapy initiation. Numbers indicate the percentage of cells in the quadrants. (B) Pie charts and bars representing the quality of the SIV-specific (Gag and Env averaged) CD4⁺ T-cell response at baseline and at d46 after ART treatment. Each section of the pie chart represents a specific combination of cytokines, as indicated by the color at the bottom of the bar graph. Data were expressed as in Figure 2B. #P < .05 vs d−7; Wilcoxon rank-sum test. (C) As in panel B but in the different treatment groups at d46 after treatment initiation. #P < .05 vs IL-15; Wilcoxon rank-sum test. (D) Percentage of SIV-specific (Gag and Env averaged) CD4⁺ T-cells with T_CM, T_TM, or T_EM cell phenotype of total memory cells at d−7 and at d46 after treatment initiation. Data are expressed as in Figure 1B.