The proportion of CD27−, CCR4+, and CD27−CCR4+ T-cells within these three subsets was significantly higher in active TB patients compared to LTBI individuals in response to PPD or ESAT-6/CFP-10 specific stimulation (Figure S3 in Supplementary Material), with the exception of CCR4 marker in response to ESAT-6/CFP-10, where no statistical significance was obtained. Here, CCR4 is linked to tuberculosis.