Figure 1.

CD4⁺/CD8⁺ T-cells specific cytokine secretion phenotype regarding active TB or LTBI. (A) Dot plots from one active TB representative donor showing the expression of CD4⁺ and CD8⁺ T-cells producing IFN-γ and/or TNF-α after PPD stimulation. The frequency of the different cytokines production profile from the total CD4⁺ and CD8⁺ T-cells is indicated in each dot plot. (B) CD4⁺ T-cells and (C) CD8⁺ T-cells cytokine secretion after PPD or ESAT6/CFP10 stimulation. Black bars represent T-cells which only produce IFN-γ cytokine. Gray bars correspond to T-cells which only produce TNF-α. Dotted bars represent T-cells producing both IFN-γ and TNF-α cytokines. Bars depict medians with interquartile ranges. Differences between conditions were calculated using the two-tailed Mann-Whitney U-test. Only significant differences are represented in the graphs. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. aTB, active TB; LTBI, latent tuberculosis infection.