T-SPOT.TB is a type of ELISPOT assay used for tuberculosis diagnosis. It is available in most European countries, the United States as well as various other territories. It was developed by researchers at the University of Oxford in England.[1] It counts the number of effector T cells, white blood cells that produce gamma interferon, in a sample of blood. This gives an overall measurement of the antigen load on the immune system, which can reveal the presence of subclinical disease. Because this does not rely on production of a reliable antibody response or recoverable pathogen, the technique can be used to detect conditions such as latent tuberculosis.[2] This technique is especially useful because it is much faster (results within 24 hours) than the previous methods and more accurate (the previous skin test would result in positive if a person doesn't have TB but has had the vaccine before or if has come into contact with the mycobacterium before). This allows physicians to treat and control the disease much better.[3]
In one study in Germany, 70 out of 72 patients with confirmed TB infection were T-SPOT.TB positive, indicating a sensitivity of 97.2%.[4]
T-SPOT.TB is a diagnostic test manufactured by Oxford Immunotec Ltd. in the UK www.oxfordimmunotec.com[5]