We hypothesised that TB patients have a predominance of the effector cell subpopulation because we observed an increase in the frequency of CD4+ T cells as a response to anti-TB treatment, and the expression of the surface markers CD45 and C–C chemokine receptor 7 (CCR7) were evaluated by flow cytometry (Förster et al. 2008). This evidence concerns the gene CCR7 and tuberculosis.