PDCD1 and tuberculosis: The gene expression (mean ± SD) of TIM-3 (4.73 ± 2.24), LAG-3 (35.3 ± 23.9), PD-1 (9.55 ± 4.93), and CTLA-4 (3.20 ± 2.12) was significantly (p = 0.0058, p < 0.0001, p = 0.0090, p = 0.0008, respectively) higher in HIV-TB co-infected individuals as compared to HIV mono-infected individuals (mean ± SD: 2.14 ± 0.89, 9.24 ± 5.62, 4.33 ± 2.28, 1.19 ± 0.894, respectively) as well as TB mono-infected individuals (mean ± SD: 1.91 ± 1.18, 2.46 ± 1.43, 3.64 ± 3.31, 0.71 ± 0.417, respectively) (Figure 2A–D, respectively).