PDF(Pubmed)
Abstract：
The emergence of the COVID-19 pandemic prompted an increased interest in seasonal human coronaviruses. OC43, 229E, NL63, and HKU1 are endemic seasonal coronaviruses that cause the common cold and are associated with generally mild respiratory symptoms. In this study, we identified cell lines that exhibited cytopathic effects (CPE) upon infection by three of these coronaviruses and characterized their viral replication kinetics and the effect of infection on host surface receptor expression. We found that NL63 produced CPE in LLC-MK2 cells, while OC43 produced CPE in MRC-5, HCT-8, and WI-38 cell lines, while 229E produced CPE in MRC-5 and WI-38 by day 3 post-infection. We observed a sharp increase in nucleocapsid and spike viral RNA (vRNA) from day 3 to day 5 post-infection for all viruses; however, the abundance and the proportion of vRNA copies measured in the supernatants and cell lysates of infected cells varied considerably depending on the virus-host cell pair. Importantly, we observed modulation of coronavirus entry and attachment receptors upon infection. Infection with 229E and OC43 led to a downregulation of CD13 and GD3, respectively. In contrast, infection with NL63 and OC43 leads to an increase in ACE2 expression. Attempts to block entry of NL63 using either soluble ACE2 or anti-ACE2 monoclonal antibodies demonstrated the potential of these strategies to greatly reduce infection. Overall, our results enable a better understanding of seasonal coronaviruses infection kinetics in permissive cell lines and reveal entry receptor modulation that may have implications in facilitating co-infections with multiple coronaviruses in humans.IMPORTANCESeasonal human coronavirus is an important cause of the common cold associated with generally mild upper respiratory tract infections that can result in respiratory complications for some individuals. There are no vaccines available for these viruses, with only limited antiviral therapeutic options to treat the most severe cases. A better understanding of how these viruses interact with host cells is essential to identify new strategies to prevent infection-related complications. By analyzing viral replication kinetics in different permissive cell lines, we find that cell-dependent host factors influence how viral genes are expressed and virus particles released. We also analyzed entry receptor expression on infected cells and found that these can be up- or down-modulated depending on the infecting coronavirus. Our findings raise concerns over the possibility of infection enhancement upon co-infection by some coronaviruses, which may facilitate genetic recombination and the emergence of new variants and strains.
摘要：
COVID-19大流行的出现促使人们对季节性人类冠状病毒的兴趣增加。OC43,229E,NL63和HKU1是引起普通感冒的地方性季节性冠状病毒，通常伴有轻度呼吸道症状。在这项研究中,我们鉴定了在被3种冠状病毒感染后表现出细胞病变效应(CPE)的细胞系,并表征了它们的病毒复制动力学和感染对宿主表面受体表达的影响.我们发现NL63在LLC-MK2细胞中产生CPE，而OC43在MRC-5、HCT-8和WI-38细胞系中产生CPE，而229E在感染后第3天在MRC-5和WI-38中产生CPE。我们观察到，从感染后第3天到第5天，所有病毒的核衣壳和刺突病毒RNA（vRNA）急剧增加；然而，在感染细胞的上清液和细胞裂解物中测量的vRNA拷贝的丰度和比例根据病毒-宿主细胞对的不同而有很大差异。重要的是,我们观察到感染时冠状病毒进入和附着受体的调节。229E和OC43的感染分别导致CD13和GD3的下调。相比之下,NL63和OC43感染导致ACE2表达增加。使用可溶性ACE2或抗ACE2单克隆抗体阻断NL63进入的尝试证明了这些策略极大地减少感染的潜力。总的来说,我们的结果使我们能够更好地了解季节性冠状病毒在允许细胞系中的感染动力学,并揭示了可能对促进人类多种冠状病毒共同感染有影响的进入受体调节.IMPORTANCE季节性人类冠状病毒是与一般轻度上呼吸道感染相关的普通感冒的重要原因，可导致某些人的呼吸道并发症。没有针对这些病毒的疫苗，只有有限的抗病毒治疗方案来治疗最严重的病例。更好地了解这些病毒如何与宿主细胞相互作用对于确定预防感染相关并发症的新策略至关重要。通过分析不同允许细胞系中的病毒复制动力学，我们发现细胞依赖性宿主因素影响病毒基因的表达和病毒颗粒的释放。我们还分析了受感染细胞上的进入受体表达，发现这些可以根据感染的冠状病毒进行上调或下调。我们的发现引起了人们对某些冠状病毒共同感染后感染增强的可能性的担忧，这可能有助于基因重组和新变体和菌株的出现。
