The frequency of PD-1 expressing cells was significantly decreased during the first 2 months of TB treatment in both the CD3+CD8+ T cells (p = 0.005, Wilcoxon ranksum test) and in the non-T cell lymphocyte subset (p = 0.001, Wilcoxon ranksum test) (Fig 3B). The gene discussed is PDCD1; the disease is tuberculosis.