Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
Biosens Bioelectron. 2013 Mar 15;41:180-5. doi: 10.1016/j.bios.2012.08.005. Epub 2012 Aug 16.
Dengue fever is one of the most neglected tropical diseases and of highest international public health importance, with 50 million cases worldwide every year. Early detection can decrease mortality rates from more than 20% to less than 1% and the relevant early diagnosis analyte is the viral non-structural glycoprotein, NS1. Currently, enzyme linked immunosorbent assay (ELISA) is the method of choice to detect NS1. However, this is a time consuming method, requiring 3-5h, and it is the bottleneck for routine of clinical analysis laboratory in epidemic periods, when hundreds of samples should be tested. Here we describe an easy method combining principles of fluorophore linked immunosorbent assay (FLISA) and enzyme linked immunospotting (ELISPOT). For detection, we used mouse anti-NS1 IgG labeled with fluorescent nanoparticles. The presented procedure needs only 4 μL of serum samples and requires 45-60 min. The detection limit, 5.2 ng/mL, is comparable to ELISA tests. The comparison of 83 samples with a commercial ELISA revealed a sensitivity of 81% and specificity of 88%. The use of fluorescent nanoparticles provides a higher sensitivity than an assay using usual fluorescent dye molecules, besides avoiding bleaching effects. Based on the results, the proposed method provides fast, specific and sensitive results, and proves to be a suitable method for Dengue NS1 detection in impoverished regions or epidemic areas.
登革热是被忽视的热带病之一，也是国际公共卫生的重点关注对象，每年全球有 5000 万例病例。早期发现可以将死亡率从 20%以上降低到 1%以下，而相关的早期诊断分析物是病毒非结构糖蛋白 NS1。目前，酶联免疫吸附试验（ELISA）是检测 NS1 的首选方法。然而，这是一种耗时的方法，需要 3-5 小时，并且在流行期间是临床分析实验室常规的瓶颈，此时需要检测数百个样本。在这里，我们描述了一种结合荧光素酶联免疫吸附试验（FLISA）和酶联免疫斑点试验（ELISPOT）原理的简单方法。在检测中，我们使用了用荧光纳米颗粒标记的抗 NS1 IgG 。该方法仅需要 4 μL 的血清样本，需要 45-60 分钟。检测限为 5.2ng/mL，与 ELISA 检测相当。对 83 个样本与商业 ELISA 的比较表明，该方法的敏感性为 81%，特异性为 88%。荧光纳米颗粒的使用提供了比使用常用荧光染料分子的检测更高的灵敏度，同时避免了漂白效应。基于这些结果，该方法提供了快速、特异和敏感的结果，并且被证明是在贫困地区或疫区检测登革热 NS1 的一种合适方法。
