ReacciónThe following technologies were included in the evaluation:
- QuantiFERON-TB Gold (QFT-G, QIAGEN, Australia);
- QuantiFERON-TB Gold In-Tube (QFT-GIT, QIAGEN, Australia); and
- T-SPOT.TB (T-Spot, Oxford Immunotec, United Kingdom)
All of these assays work on the principle that the T-cells of an individual who has acquired TB infection will respond to re-stimulation with antigens specific to Mtb by secreting IFN-γ. The QuantiFERON-TB Gold, and the newer version QuantiFERON-TB Gold In-Tube, are whole-bloodbased ELISAs that measure the amount of IFN-γ produced in response to specific Mtb antigens (QFT-G: ESAT-6 and CFP-10; QFT-GIT: ESAT-6, CFP-10 and TB7.7). In contrast, the ELISPOTbased T-Spot measures the number of peripheral mononuclear cells that produce INF-g after stimulation with ESAT-6 and CFP-10.