A New Diagnostic Test for Detecting Infection of Mycobacterium Tuberculosis Based on in Vitro IFN-γ Release Assay by Whole Blood Culture: Its Establishment and Primary Application
|Course||Biochemistry and Molecular Biology|
|Keywords||Mycobacterium tuberculosis Whole blood Cultured in vitro T-cell immunity gamma - interferon|
Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (Mycobacterium tuberculosis, MTB) infection to respiratory infections, serious threat to human health. Showing a trend of expanding the spread of tuberculosis. Statistics show that over 1/3 of people infected with Mycobacterium tuberculosis, but the existing methods for the diagnosis of tuberculosis infection or defect exists, the outstanding problems sensitivity and low specificity. Therefore a need for a new diagnostic technologies to fill the gap between the inadequacies of the existing methods. Mycobacterium tuberculosis infection with the human immune system is activated and generated for Mycobacterium tuberculosis effector T lymphocytes and memory T lymphocytes, these specific T lymphocytes in Mycobacterium tuberculosis antigen is encountered again, then can be activated, secrete cytokines (such as IFN-gamma). Accordingly, and reference has been reported in the literature, the present study was to establish a new tuberculosis in vitro diagnostic reagents - whole blood tuberculosis IFN-gamma in vitro release test (TB IFN-γrelease in Assay, TB-IGRA) with cells in vitro culture system and cytokine quantification system, the detection time is about 24 hours. After a preliminary clinical validation, TB-IGRA sensitivity of 95.8% and a specificity of 96.3%. The reagent not only have a higher detection rate of tuberculosis in extrapulmonary tuberculosis detection rate of 92.9%. In the study of patients treated before and after the changes in TB-IGRA results found, IGRA detection value that is stimulated to produce IFN-gamma concentration decreases with the rehabilitation of patients, the negative rate of 53.8%, suggesting that the results of this reagent with the patient's course of The development has a certain relationship, and can be as prompt as an indicator of duration. The results of this reagent with tuberculosis exposure is compared with the tuberculin skin test (TST) decreases due to the detection of TST specificity by a large number of BCG vaccination, easy to produce in a tuberculosis outbreak investigation false-positive TB-IGRA Mi fill the gap. Also found that TB-IGRA reagent and control reagent QFT established in this study in asymptomatic carriers of tuberculosis have the same detection capability. This research has successfully established a whole blood tuberculosis IFN-gamma in vitro release test kit, and verify that the relevant parameters meet the requirements. This kit is used in clinical preliminary verification, found in a number of areas with the need for further study, in a follow-up study to verify the reliability of the reagents and clinical value.