Here, we worked with cohorts of young, hospitalized, Ugandan children with confirmed and unconfirmed TB, as well as non-TB LRTI, to compare the expression of proinflammatory cytokines IFN-γ, IL-2, and TNF-α by mycobacterial-reactive CD4+ and CD8+ T cells, to those observed among Ugandan adults with confirmed TB. The gene discussed is IFNG; the disease is tuberculosis.