IFNG and tuberculosis: The QFT-GIT test is an immunological method for the diagnosis of tuberculosis that uses an enzyme-linked immunosorbent assay (ELISA) to detect the levels of IFN-γ produced upon stimulation with the tuberculosis-specific antigens ESAT-6, CFP-10, and TB7.7, which are specifically expressed by M.tuberculosis and all BCG strains and the majority of non-tubercle bacteria do not contain these antigens.