Zheng Xiao-fang, Yi Ling, Wei Pan-jian, Jia Hong-yan, Li Hui-wen, Zhao Yan-lin, Zhang Hong-tao
Beijing Tuberculosis & Thoracic Tumor Research Institute, Beijing, China.
Zhonghua Yi Xue Za Zhi. 2011 Dec 27;91(48):3405-8.
To explore the roles of BCG-depleted immunodominant antigens derived from M. tuberculosis in serological tests for tuberculosis (TB).
Four different combinations of current mainstream antigens used for serological diagnosis of TB were selected: Reagent A [Mycobacterium TB immunoglobulin G (IgG) antibody assay kit]; Reagent B (Mycobacterium TB detection kit); Reagent C (M. tuberculosis-specific antibody detection kit); Reagent D [Active TB antibody detection enzyme-linked immunosorbent assay (ELISA) system]. Immunological methods of Western blot, colloidal gold and ELISA were developed to test the antibodies in 109 patients with active tuberculosis (TB) and 97 healthy populations. They were divided into purified protein derivative of tuberculin (PPD) positive and negative groups. Bayesian statistical analysis was used to analyze the influences of variable combinations of different antigens on the detection accuracy of TB.
For Reagent A, B, C, D, the detection rates of IgG antibodies in the patients with active TB were 80.0%, 66.7%, 80.7%, 56.0% versus 23.9%, 8.9%, 6.6% and 1.0% respectively in healthy populations. The TB antibody detection rates in four TB patient populations were all higher than that in healthy populations (χ(2) = 47.53, 51.59, 90.48, 69.68, all P < 0.01). The TB antibody detection rates of Reagents A and B increased with the intensity of positive reaction to PPD in healthy populations (χ(2) = 2.124, 2.220, all P < 0.05) while those of Reagents C, D in healthy populations were irrelevant to PPD reaction. (χ(2) = 0.122, 0.479, all P > 0.05). Reagent D has the highest accuracy. The immunoglobulin M (IgM) antibody detection rate of Reagent D was only 2.1% in the patients with active TB.
The detecting sensitivity of TB IgG antibodies is associated with antigen selection. And it is also positively correlated with the number of combined antigens. High-sensitivity detection is often accompanied by a loss of specificity. With the BCG-depleted antigens derived from M. tuberculosis, the specificity of serological test for TB may significantly improve.
探讨结核分枝杆菌减毒免疫显性抗原在结核病血清学检测中的作用。
选取目前用于结核病血清学诊断的四种不同主流抗原组合：试剂A[结核分枝杆菌免疫球蛋白G（IgG）抗体检测试剂盒]；试剂B（结核分枝杆菌检测试剂盒）；试剂C（结核分枝杆菌特异性抗体检测试剂盒）；试剂D[活动性结核抗体检测酶联免疫吸附测定（ELISA）系统]。采用蛋白质印迹法、胶体金法和ELISA等免疫学方法检测109例活动性肺结核患者和97例健康人群的抗体。将他们分为结核菌素纯蛋白衍生物（PPD）阳性和阴性组。采用贝叶斯统计分析不同抗原变量组合对结核病检测准确性的影响。
对于试剂A、B、C、D，活动性肺结核患者中IgG抗体的检出率分别为80.0%、66.7%、80.7%、56.0%，而健康人群中分别为23.9%、8.9%、6.6%和1.0%。四个肺结核患者群体的结核抗体检出率均高于健康人群（χ(2)=47.53、51.59、90.48、69.68，均P<0.01）。试剂A和B的结核抗体检出率随健康人群中PPD阳性反应强度的增加而升高（χ(2)=2.124、2.220，均P<0.05），而试剂C、D在健康人群中的检出率与PPD反应无关（χ(2)=0.122、0.479，均P>0.05）。试剂D的准确性最高。试剂D在活动性肺结核患者中的免疫球蛋白M（IgM）抗体检出率仅为2.1%。
结核IgG抗体检测的敏感性与抗原选择有关，且与联合抗原的数量呈正相关。高敏感性检测往往伴随着特异性的丧失。采用结核分枝杆菌减毒抗原，结核病血清学检测的特异性可能会显著提高。
