State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, People's Republic of China.
Institute of Infectious disease, Guangzhou Eighth People's Hospital of Guangzhou Medical University, Guangzhou, People's Republic of China.
Emerg Microbes Infect. 2020 Jan 29;9(1):246-255. doi: 10.1080/22221751.2020.1717999. eCollection 2020.
Human coronavirus NL63 (HCoV-NL63) is primarily associated with common cold in children, elderly and immunocompromised individuals. Outbreaks caused by HCoV-NL63 are rare. Here we report a cluster of HCoV-NL63 cases with severe lower respiratory tract infection that arose in Guangzhou, China, in 2018. Twenty-three hospitalized children were confirmed to be HCoV-NL63 positive, and most of whom were hospitalized with severe pneumonia or acute bronchitis. Whole genomes of HCoV-NL63 were obtained using next-generation sequencing. Phylogenetic and single amino acid polymorphism analyses showed that this outbreak was associated with two subgenotypes (C3 and B) of HCoV-NL63. Half of patients were identified to be related to a new subgenotype C3. One unique amino acid mutation at I507 L in spike protein receptor binding domain (RBD) was detected, which segregated this subgenotype C3 from other known subgenotypes. Pseudotyped virus bearing the I507 L mutation in RBD showed enhanced entry into host cells as compared to the prototype virus. This study proved that HCoV-NL63 was undergoing continuous mutation and has the potential to cause severe lower respiratory disease in humans.
人冠状病毒 NL63（HCoV-NL63）主要与儿童、老年人和免疫功能低下者的普通感冒有关。由 HCoV-NL63 引起的暴发很少见。在这里，我们报告了 2018 年在中国广州发生的一组由 HCoV-NL63 引起的严重下呼吸道感染的病例。23 名住院的儿童被确认为 HCoV-NL63 阳性，其中大多数因严重肺炎或急性支气管炎住院。使用下一代测序获得了 HCoV-NL63 的全基因组。系统发育和单氨基酸多态性分析表明，此次暴发与 HCoV-NL63 的两个亚属（C3 和 B）有关。一半的患者被确定与一种新的亚属 C3 有关。在刺突蛋白受体结合域（RBD）中检测到 I507L 的一个独特的氨基酸突变，该突变将该亚属 C3 与其他已知的亚属区分开来。与原型病毒相比，携带 RBD 中 I507L 突变的假型病毒显示出增强的进入宿主细胞的能力。这项研究证明 HCoV-NL63 正在不断发生突变，并有可能导致人类严重的下呼吸道疾病。
