State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.
Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China.
Viruses. 2009 Jun;1(1):57-71. doi: 10.3390/v1010057. Epub 2009 Jun 11.
After human coronaviruses OC43, 229E and NL63, human coronavirus HKU1 (HCoV-HKU1) is the fourth human coronavirus discovered. HCoV-HKU1 is a group 2a coronavirus that is still not cultivable. The G + C contents of HCoV-HKU1 genomes are 32%, the lowest among all known coronaviruses with complete genome sequences available. Among all coronaviruses, HCoV-HKU1 shows the most extreme codon usage bias, attributed most importantly to severe cytosine deamination. All HCoV-HKU1 genomes contain unique tandem copies of a 30-base acidic tandem repeat of unknown function at the N-terminus of nsp3 inside the acidic domain upstream of papain-like protease 1. Three genotypes, A, B and C, of HCoV-HKU1 and homologous recombination among their genomes, are observed. The incidence of HCoV-HKU1 infections is the highest in winter. Similar to other human coronaviruses, HCoV-HKU1 infections have been reported globally, with a median (range) incidence of 0.9 (0 - 4.4) %. HCoV-HKU1 is associated with both upper and lower respiratory tract infections that are mostly self-limiting. The most common method for diagnosing HCoV-HKU1 infection is RT-PCR or real-time RT-PCR using RNA extracted from respiratory tract samples such as nasopharyngeal aspirates (NPA). Both the pol and nucleocapsid genes have been used as the targets for amplification. Monoclonal antibodies have been generated for direct antigen detection in NPA. For antibody detection, Escherichia coli BL21 and baculovirus-expressed recombinant nucleocapsid of HCoV-HKU1 have been used for IgG and IgM detection in sera of patients and normal individuals, using Western blot and enzyme-linked immunoassay.
人冠状病毒 OC43、229E 和 NL63 之后，人冠状病毒 HKU1（HCoV-HKU1）是被发现的第四种人类冠状病毒。HCoV-HKU1 是一株 2a 冠状病毒，目前仍无法培养。HCoV-HKU1 基因组的 G+C 含量为 32%，是所有具有完整基因组序列的已知冠状病毒中最低的。在所有的冠状病毒中，HCoV-HKU1 显示出最极端的密码子使用偏好，这主要归因于严重的胞嘧啶脱氨酶作用。所有 HCoV-HKU1 基因组在木瓜蛋白酶样蛋白酶 1 上游的酸性结构域内 nsp3 的 N 端都含有独特的串联拷贝的 30 碱基酸性串联重复序列，其功能未知。HCoV-HKU1 有 A、B 和 C 三种基因型，以及它们之间基因组的同源重组。HCoV-HKU1 感染的发生率在冬季最高。与其他人类冠状病毒一样，HCoV-HKU1 感染在全球范围内都有报道，中位数（范围）发病率为 0.9（0-4.4）%。HCoV-HKU1 与上呼吸道和下呼吸道感染有关，大多数情况下是自限性的。诊断 HCoV-HKU1 感染最常用的方法是 RT-PCR 或实时 RT-PCR，使用从呼吸道样本（如鼻咽抽吸物）提取的 RNA。聚合酶和核衣壳基因都被用作扩增的靶点。已经生成了单克隆抗体，用于直接检测鼻咽抽吸物中的抗原。对于抗体检测，已使用大肠杆菌 BL21 和杆状病毒表达的重组 HCoV-HKU1 核衣壳蛋白，通过 Western blot 和酶联免疫吸附试验，在患者和正常人的血清中检测 IgG 和 IgM。
