Application progress of T cell spot test in diagnosis of tuberculosis infection by interferon-γ release analysis

Zhang Jianying

doi:10.3969/j.issn.1674-7151.2025.03.023

Abstract：Tuberculosis infection may harm any organ in the body,but the risk of lung damage is the highest,accounting for about 80%,which is pulmonary tuberculosis.In the past,the tuberculin skin test was used to diagnose tuberculosis infection,but the method gradually exposed many defects during the application process.Therefore,in order to further optimize the diagnostic effect of tuberculosis infection,the article explores the application of T cell spot test(T-SPOT.TB)diagnostic method.If tuberculosis infection exists,the immune system will produce targeted memory T cells and release interferon-γ.According to the analysis of research results obtained by domestic scholars,the sensitivity and specificity of T-SPOT.TB in diagnosing different types of tuberculosis infections vary among different scholars,but they are generally not less than 70%.The purpose of the article is to analyze the application progress of T-SPOT.TB diagnostic method,elucidate the response methods of human immune barrier after tuberculosis infection,explain the principle of T-SPOT.TB,and point out that T-SPOT.TB experiment is effective when the number of spots in the blank and positive control wells reaches 10 or less and 20 or more,respectively.When the number of spots in the blank control well does not exceed 6,subtracting the number of spots in any experimental well,and the result is greater than 6,it is considered positive.When the number of spots in the blank control well is greater than 6,and the ratio of the number of spots in any experimental well to it is greater than 2,it is considered positive.The application progress of T-SPOT.TB in active and latent tuberculosis,as well as extrapulmonary tuberculosis,was analyzed in detail.