IL21 and tuberculosis: Given the limitations of current TB diagnostics and recent progress in immunomics, we employed flow cytometry to systematically profile the expression of cytokines (IFN‐γ, TNF‐α, IL‐2, IL‐10, IL‐17, IL‐21) and immune checkpoint markers (lymphocyte activation gene 3 [LAG‐3], T‐cell immunoglobulin and mucin domain‐containing 3 [TIM‐3], PD‐1, programmed death‐ligand 1 [PD‐L1], and cytotoxic T‐lymphocyte–associated protein 4 [CTLA‐4]) on naïve/memory CD4+/CD8+ T cells from TB patients.