Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangzhou, Guangdong, China.
College of Food Science, South China Agricultural University, Guangzhou, China.
J Med Virol. 2024 Mar;96(3):e29487. doi: 10.1002/jmv.29487.
Human norovirus (HuNoV) is the most predominant viral agents of acute gastroenteritis. Point-of-care testing (POCT) based on lateral flow immunochromatography (LIFC) has become an important tool for rapid diagnosis of HuNoVs. However, low sensitivity and lack of quantitation are the bottlenecks of traditional LIFC. Thus, we established a rapid and accurate technique that combined immunomagnetic enrichment (IM) with LFIC to identify GII HuNoVs in fecal specimens. Before preparing immunofluorescent nanomagnetic microspheres and achieving the effect of HuNoV enrichment in IM and fluorescent signal in LFIC, amino-functionalized magnetic beads (MBs) and carboxylated quantum dots (QDs) were coupled at a mass ratio of 4:10. Anti-HuNoV monoclonal antibody was then conjugated with QDs-MB. The limit of detection was 1.56 × 10 copies/mL, and the quantitative detection range was 1.56 × 10 copies/mL-1 × 10 copies/mL under optimal circumstances. The common HuNoV genotypes GII.2, GII.3, GII.4, and GII.17 can be detected, there was no cross-reaction with various enteric viruses, including rotavirus, astrovirus, enterovirus, and sapovirus. A comparison between IM-LFIC and RT-qPCR for the detection of 87 fecal specimens showed a high level of agreement (kappa = 0.799). This suggested that the method is rapid and sensitive, making it a promising option for point-of-care testing in the future.
人诺如病毒（HuNoV）是急性肠胃炎的主要病毒性病原体。基于侧向流动免疫层析（LIFC）的即时检测（POCT）已成为快速诊断 HuNoVs 的重要工具。然而，传统 LIFC 的灵敏度低和缺乏定量检测是其瓶颈。因此，我们建立了一种快速而准确的技术，该技术结合免疫磁珠富集（IM）和 LFIC 来鉴定粪便标本中的 GII HuNoVs。在制备免疫荧光纳米磁珠并在 IM 中实现 HuNoV 富集和 LFIC 中的荧光信号之前，将氨基功能化磁珠（MBs）和羧基化量子点（QDs）以质量比 4:10 偶联。然后，将抗 HuNoV 单克隆抗体与 QDs-MB 偶联。在最佳条件下，检测限为 1.56×10 拷贝/mL，定量检测范围为 1.56×10 拷贝/mL-1×10 拷贝/mL。可以检测到常见的 HuNoV 基因型 GII.2、GII.3、GII.4 和 GII.17，与各种肠道病毒（包括轮状病毒、星状病毒、肠病毒和 sapovirus）没有交叉反应。IM-LFIC 与 RT-qPCR 检测 87 份粪便标本的比较显示出高度一致性（kappa=0.799）。这表明该方法快速灵敏，有望成为未来即时检测的一种选择。
