74281-7
LaboratoryMycobacterium tuberculosis stimulated gamma interferon and spot count panel - Blood
Definition
Interferon gamma release assays (IGRAs) are used for the detection of M. tuberculosis. This panel was created for, but not limited in use to, Oxford Immunotec's T-SPOT.TB assay, which uses enzyme-linked immunospot (ELISPOT) methodology to enumerate M. tuberculosis-sensitized T cells by capturing interferon-gamma (IFN-y) in the vicinity of T cells in the patient's whole blood. Cells are spun and, using the ficoll centrifugation procedure, the polys and RBCs layer together in the bottom fraction with peripheral blood mononuclear cells (PBMCs) in the middle. The PBMCs are pipetted out to yield about 250,000 PBMCs per aliquot. They are incubated with M. tuberculosis specific antigens (ESAT-6, CFP10) in two separate wells, a phytohemagglutinin (PHA) control (a mitogenic stimulator) in another well, and a negative control in a fourth well. Incubation with the antigens allows for stimulation of any sensitized T cells present. Evaluating the number of antigen incubated spots compared to the positive and negative control spots provides a measurement of the abundance of M. tuberculosis sensitive T cells in the patient's blood.
LOINC 6-Axis Classification
Component
Mycobacterium tuberculosis stimulated gamma interferon & spot count panel
Property
-
Time Aspect
Pt
System
Bld
Scale Type
-
Method Type
N/A
Details
Class
PANEL.MICRO
Order/Observation
Order
Short Name
M TB IFN-g+spot Pnl Bld
Display Name
M. tuberculosis stim IFN-g and spot count panel (Bld)
Related Names
Frequently Asked Questions
What is LOINC code 74281-7?
LOINC code 74281-7 identifies "Mycobacterium tuberculosis stimulated gamma interferon and spot count panel - Blood". Interferon gamma release assays (IGRAs) are used for the detection of M. tuberculosis. This panel was created for, but not limited in use to, Oxford Immunotec's T-SPOT.TB assay, which uses enzyme-linked immunospot (ELISPOT) methodology to enumerate M. tuberculosis-sensitized T cells by capturing interferon-gamma (IFN-y) in the vicinity of T cells in the patient's whole blood. Cells are spun and, using the ficoll centrifugation procedure, the polys and RBCs layer together in the bottom fraction with peripheral blood mononuclear cells (PBMCs) in the middle. The PBMCs are pipetted out to yield about 250,000 PBMCs per aliquot. They are incubated with M. tuberculosis specific antigens (ESAT-6, CFP10) in two separate wells, a phytohemagglutinin (PHA) control (a mitogenic stimulator) in another well, and a negative control in a fourth well. Incubation with the antigens allows for stimulation of any sensitized T cells present. Evaluating the number of antigen incubated spots compared to the positive and negative control spots provides a measurement of the abundance of M. tuberculosis sensitive T cells in the patient's blood.
What does 74281-7 measure?
This code measures Mycobacterium tuberculosis stimulated gamma interferon & spot count panel in Bld. It belongs to the PANEL.MICRO class in the LOINC classification.
What is LOINC?
LOINC (Logical Observation Identifiers Names and Codes) is a universal standard for identifying laboratory and clinical observations. It is maintained by the Regenstrief Institute and used worldwide for health data exchange.