From the 1 Central Laboratory, Beijing Key Laboratory of Organ Transplantation and Immunology Regulation, 309th Hospital of the Chinese People's Liberation Army , Beijing , China.
Infect Dis (Lond). 2015 Sep;47(9):643-9. doi: 10.3109/23744235.2015.1043941. Epub 2015 May 11.
Commercial serological tests for the diagnosis of tuberculosis (TB) show poor sensitivity and specificity, and a new approach to antigen screening is required to improve the accuracy of serodiagnosis.
Using an indirect enzyme-linked immunosorbent assay (ELISA), we evaluated the responses of IgG and IgM antibodies to the recombinant PstS1-LEP protein expressed in Escherichia coli, a polyprotein of PstS1 and line multi-epitopes polypeptide (LEP).
The mixture of anti-human IgG and IgM added to a well [Ig(G + M)], which was different from the combination of IgG and IgM (IgG + IgM), had a stronger immunoreactivity to PstS1-LEP than the single antibody. IgG and Ig(G + M), but not IgM against the PstS1-LEP protein effectively distinguished TB patients from patients with nontuberculous pulmonary disease (NTBPD) and healthy controls (HCs). Compared with IgG, the sensitivities of Ig(G + M) and IgG + IgM varied from 71.4% to 77.6% and 72.7% in pulmonary TB (PTB) patients and from 42.1% to 64.0% and 55.8% in extrapulmonary TB (EPTB) patients, respectively. The specificity of Ig(G + M) did not decrease, and was higher than that provided by IgG + IgM in HCs with positive tuberculin skin test.
These findings suggest that PstS1-LEP can act as a candidate for detecting Ig(G + M) in serum from PTB and EPTB patients.
用于诊断结核病（TB）的商业血清学检测显示出较差的敏感性和特异性，因此需要新的抗原筛选方法来提高血清学诊断的准确性。
我们使用间接酶联免疫吸附试验（ELISA）评估了针对大肠杆菌中表达的重组 PstS1-LEP 蛋白的 IgG 和 IgM 抗体的反应，该蛋白是 PstS1 和线多表位多肽（LEP）的多蛋白。
与 IgG 和 IgM 的组合（IgG + IgM）不同，加入孔中的抗人 IgG 和 IgM 的混合物（Ig（G + M））对 PstS1-LEP 具有比单个抗体更强的免疫反应性。IgG 和 Ig（G + M），但不是针对 PstS1-LEP 蛋白的 IgM，可有效区分结核病患者与非结核性肺病（NTBPD）患者和健康对照（HC）。与 IgG 相比，Ig（G + M）和 IgG + IgM 的敏感性在肺结核（PTB）患者中分别从 71.4％到 77.6％和 72.7％变化，在肺外结核病（EPTB）患者中分别从 42.1％到 64.0％和 55.8％变化。Ig（G + M）的特异性没有降低，并且在结核菌素皮肤试验阳性的 HC 中，其特异性高于 IgG + IgM。
这些发现表明 PstS1-LEP 可以作为检测 PTB 和 EPTB 患者血清中 Ig（G + M）的候选物。
