TB is a chronic infectious disease which is caused by mycobacterium tuberculosis complex (TB Bacterium), mostly infected through respiratory tract or digestive tract. All human organs such as liver, kidney, brain could be infected especially lungs which could be 80%-90% of total TB cases. Tuberculosis patients often have fever, night sweats, fatigue, weight loss, loss of appetite, and cough blood. One third of the world's people currently have M. tuberculosis infection. And about 10% of them will develop into active tuberculosis.
This assay is based on a chemiluminescent microparticle immunoassay (CLIA Microparticles) using specific antigen representing to Mycobacterium tuberculosis peptides to stimulate T cells (CD8+, CD4+) in fresh peripheral venous anticoagulant blood to release interferon-γ (interferon gamma release assay, IGRA). Detection of interferon-γ is used to identify specific T-cells immunological reaction to those peptide antigens that are associated with Mycobacterium tuberculosis infection (active tuberculosis and latent tuberculosis infection).
 Pai, Madhukar et al. "Interferon-gamma assays in the immunodiagnosis of tuberculosis: a systematic review." The Lancet. Infectious diseases vol. 4,12 (2004): 761-76.
 Tsiouris, Simon J et al. "Sensitivity analysis and potential uses of a novel gamma interferon release assay for diagnosis of tuberculosis." Journal of clinical microbiology vol. 44,8 (2006): 2844-50.