Institute for Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing 100091, China.
Clin Chim Acta. 2010 Oct 9;411(19-20):1520-8. doi: 10.1016/j.cca.2010.06.014. Epub 2010 Jun 22.
The detection of Mycobacteriumtuberculosis (MTB)-specific human antibodies has been an important diagnostic aid in the diagnosis of TB, especially for the bacterium-negative TB. The humoral antibody responses to different antigens of M.tuberculosis (MTB) are heterogeneous in active TB patients. Hence, detection of antibody responses to several MTB antigens may improve the sensitivity and specificity of serological diagnosis of active TB.
Seventeen MTB antigens (38kD, 16kD, Ag85A, Ag85B, MPT32, MPT63, MPT64, Mtb39, MTB48, Mtb81, MTC28, Rv1009, ESAT6, CFP10, CFP10-ESAT6, katG, and LAM) were prepared by cloning, expression, and purification from E. coli, and their antigenicities were evaluated in the antibody responses of 210 active TB patients (103 sera from smear- or culture-positive patients, and 107 from smear- or culture-negative patients) and 192 healthy control (95 sera from purified protein derivative-negative healthy donors, and 97 sera from BCG-vaccinated individuals) by an enzyme-linked immunosorbent assay (ELISA).
The levels of antibodies against these antigens in bacterium-negative TB patients were significantly higher than that in healthy controls (p<0.001). The sensitivity with individual antigens to detect antibody responses ranged from 55.7 to 82.9%, with the specificity from 62.0 to 92.2%. Importantly, the sensitivity with five antigens (LAM, 38kD, katG, 16kD, and MPT63 or Mtb39) to detect antibody responses reached 69.5% (146/210), with a specificity of 91.1% (17/192), and the sensitivity with another five antigens (LAM, katG, 16kD, Mtb39 and Mtb81) to detect antibody responses reached 67.1% (141/210), with a specificity of 92.7% (14/192).
The combination of optimal multiple antigens to detect anti-MTB antibody responses increased the sensitivity and specificity. Therefore, detection of anti-MTB antibody responses with multiple antigens may be valuable in the clinical diagnosis of TB patients.
检测结核分枝杆菌（MTB）特异性人抗体一直是诊断结核病，尤其是菌阴性结核病的重要辅助诊断方法。活动性结核病患者对 MTB 不同抗原的体液抗体反应存在异质性。因此，检测针对几种 MTB 抗原的抗体反应可能会提高血清学诊断活动性结核病的敏感性和特异性。
从大肠杆菌中通过克隆、表达和纯化制备了 17 种 MTB 抗原（38kD、16kD、Ag85A、Ag85B、MPT32、MPT63、MPT64、Mtb39、MTB48、Mtb81、MTC28、Rv1009、ESAT6、CFP10、CFP10-ESAT6、katG 和 LAM），并用酶联免疫吸附试验（ELISA）检测了 210 例活动性结核病患者（103 例来自涂片或培养阳性患者，107 例来自涂片或培养阴性患者）和 192 例健康对照者（95 例来自纯化蛋白衍生物阴性健康供者，97 例来自卡介苗接种者）的抗体反应中的抗原性。
菌阴性结核病患者针对这些抗原的抗体水平明显高于健康对照者（p<0.001）。用单个抗原检测抗体反应的敏感性范围为 55.7%至 82.9%，特异性范围为 62.0%至 92.2%。重要的是，用五种抗原（LAM、38kD、katG、16kD 和 MPT63 或 Mtb39）检测抗体反应的敏感性达到 69.5%（146/210），特异性为 91.1%（17/192），用另外五种抗原（LAM、katG、16kD、Mtb39 和 Mtb81）检测抗体反应的敏感性达到 67.1%（141/210），特异性为 92.7%（14/192）。
联合使用最佳多种抗原检测抗 MTB 抗体反应可提高敏感性和特异性。因此，用多种抗原检测抗 MTB 抗体反应可能对结核病患者的临床诊断具有重要价值。
