结核分枝杆菌融合抗原Rv3914-6His的原核表达、纯化与抗原性检测

Prokaryotic Expression,Purification of Mycobacterium tuberculosis Antigen Rv3914-6His and Detection of the Antigenicity

血清学诊断是目前临床诊断中应用最为广泛的方法之一,用原核表达并鉴定了系列结核分枝杆菌抗原融合蛋白Rv1908c-6His、Rv0733-6His、Rv0899-6His、Rv1411c-6His和Rv3914-6His,并以此包被酶标板,以Rv2031c-6His为阳性对照,采用间接ELISA方法比较了34例活动性结核病患者与35例健康体检者血清中抗结核分枝杆菌抗原的IgG水平。结果显示,活动性结核病患者中针对Rv1411c-6His、Rv3914-6His和Rv2031c-6His的IgG水平明显高于健康体检者,其中Rv3914-6His的AUC值(0.786 7)略高于目前临床应用的类似于16 ku的抗原Rv2031c-6His(AUCRv2031c=0.754),提示Rv3914抗原可能是结核病血清诊断的新的候选标志物。

As the most widely used diagnostic method in clinic,serodiagnosis and its application in tuberculosis（TB） still need to be improved and validated due to its limitation in accuracy and rapidness.A group of recombinant expression vector system constructed by cloning Rv1908c,Rv0733,Rv0899,Rv1411c and Rv3914 gene of Mycobacterium tuberculosis（Mtb） into the prokaryotic expression plasmid pET-32b was transformed into E.coli for induction and expression fusion antigens to determine their potentiality in diagnostic application.The ELISA plates were coated with these fusion antigens.Through indirect ELISA,the antigen binding with specific IgG levels between active TB patients and healthy control was compared.The results indicated that IgG levels against Rv1411c-6His,Rv3914-6His and Rv2031c-6His were significantly higher in serum of active TB patients than in that of healthy controls.More interesting,the AUC value of Rv3914-6His（0.7867） was higher than that of Rv2031c-6His（0.754） which was widely used in clinic.The results prompted that Rc3914-6His might be a useful candidate antigen in the diagnosis of Mtb.