CD4 and tuberculosis: In agreement with previous reports, CD27 expression was downregulated on ESAT-6/CFP-10-stimulated CD4+ T-cells with an effector memory phenotype characterized by a high proportion of CD27−CD45RA−CCR7− within the total cytokine+ compartment (p < 0.001 for HIV−TB vs. LTBI and p = 0.02 for HIV+TB vs. LTBI, Figure 7B).