Non-invasive bioluminescence imaging of HCoV-OC43 infection and therapy in the central nervous system of live mice

• Published in: Antiviral research Vol. 173; p. 104646
• Main Authors: Niu, Junwei, Shen, Liang, Huang, Baoying, Ye, Fei, Zhao, Li, Wang, Huijuan, Deng, Yao, Tan, Wenjie
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-01-2020
• Subjects: Bioluminescence imaging; Chloroquine; Coronavirus; Mouse; Therapy; Therapy; Coronavirus; Bioluminescence imaging; Mouse; Chloroquine
• ISSN: 0166-3542; 1872-9096
• DOI: 10.1016/j.antiviral.2019.104646

Human coronaviruses (HCoVs) are important pathogens that cause upper respiratory tract infections and have neuroinvasive abilities; however, little is known about the dynamic infection process of CoVs in vivo, and there are currently no specific antiviral drugs to prevent or treat HCoV infection. Here, we verified the replication ability and pathogenicity of a reporter HCoV-OC43 strain expressing Renilla luciferase (Rluc; rOC43-ns2DelRluc) in mice with different genetic backgrounds (C57BL/6 and BALB/c). Additionally, we monitored the spatial and temporal progression of HCoV-OC43 through the central nervous system (CNS) of live BALB/c mice after intranasal or intracerebral inoculation with rOC43-ns2DelRluc. We found that rOC43-ns2DelRluc was fatal to suckling mice after intranasal inoculation, and that viral titers and Rluc expression were detected in the brains and spinal cords of mice infected with rOC43-ns2DelRluc. Moreover, viral replication was initially observed in the brain by non-invasive bioluminescence imaging before the infection spread to the spinal cord of BALB/c mice, consistent with its tropism in the CNS. Furthermore, the Rluc readout correlated with the HCoV replication ability and protein expression, which allowed quantification of antiviral activity in live mice. Additionally, we validated that chloroquine strongly inhibited rOC43-ns2DelRluc replication in vivo. These results provide new insights into the temporal and spatial dissemination of HCoV-OC43 in the CNS, and our methods provide an extremely sensitive platform for evaluating the efficacy of antiviral therapies to treat neuroinvasive HCoVs in live mice.
•We verified the pathogenicity of a reporter HCoV-OC43 strain expressing Renilla luciferase (rOC43-ns2DelRluc) in mice.•HCoV-OC43 spatio-temporal progression in CNS of mice was monitored by non-invasive bioluminescence imaging (BLI).•Chloroquine was validated strongly inhibited rOC43-ns2DelRluc replication in in live mice.•rOC43-ns2DelRluc-based BLI was reported as a promising platform for non-invasively screening antiviral compounds in vivo.