IFNG and tuberculosis: Interferongamma release assays (IGRA) are widely used in healthcarefacilities to probe the IFN-γ biomarker to test for TB.86 Notably, the IGRA test does not directly measurethe TB organism, but indirectly measures the cellular immune responsesto the mycobacterial protein biomarkers or antigens, such as earlysecreted antigenic target-6 (ESAT-6) and 10 kDa culture filtrate protein(CFP-10), in vitro.