IFNG and tuberculosis: However, dissecting out the composition of ESAT-6/CFP-10-specific IFN-γ-secreting T cell populations in patients during the substantial reductions in pathogen load induced by the induction phase of anti-TB treatment revealed remarkably consistent dynamic changes in the underlying IFN-γ-only-secreting T cells and dual IFN-γ/IL-2-secreting T cells that together comprise the overall IFN-γ response, with the former declining and the latter increasing in 18 out of 19 patients.