Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
En Carta Diagnostics, Paris, France.
Nat Biomed Eng. 2022 Mar;6(3):246-256. doi: 10.1038/s41551-022-00850-0. Epub 2022 Mar 7.
In low-resource settings, resilience to infectious disease outbreaks can be hindered by limited access to diagnostic tests. Here we report the results of double-blinded studies of the performance of paper-based diagnostic tests for the Zika and chikungunya viruses in a field setting in Latin America. The tests involved a cell-free expression system relying on isothermal amplification and toehold-switch reactions, a purpose-built portable reader and onboard software for computer vision-enabled image analysis. In patients suspected of infection, the accuracies and sensitivities of the tests for the Zika and chikungunya viruses were, respectively, 98.5% (95% confidence interval, 96.2-99.6%, 268 serum samples) and 98.5% (95% confidence interval, 91.7-100%, 65 serum samples) and approximately 2 aM and 5 fM (both concentrations are within clinically relevant ranges). The analytical specificities and sensitivities of the tests for cultured samples of the viruses were equivalent to those of the real-time quantitative PCR. Cell-free synthetic biology tools and companion hardware can provide de-centralized, high-capacity and low-cost diagnostics for use in low-resource settings.
在资源有限的环境中，由于诊断测试的获取有限，对传染病爆发的弹性可能会受到阻碍。在这里，我们报告了在拉丁美洲实地环境中对基于纸张的寨卡病毒和基孔肯雅病毒诊断测试性能进行双盲研究的结果。这些测试涉及一种依赖等温扩增和链置换反应的无细胞表达系统、一个专门设计的便携式读取器以及用于计算机视觉辅助图像分析的内置软件。在疑似感染的患者中，这些用于检测寨卡病毒和基孔肯雅病毒的测试的准确率和灵敏度分别为 98.5%（95%置信区间，96.2-99.6%，268 份血清样本）和 98.5%（95%置信区间，91.7-100%，65 份血清样本），检测限约为 2 aM 和 5 fM（两种浓度均在临床相关范围内）。这些病毒的培养样本的测试分析特异性和灵敏度与实时定量 PCR 相当。无细胞合成生物学工具和配套硬件可为资源有限的环境提供去中心化、大容量和低成本的诊断。
