In vitro inhibition of Japanese encephalitis virus replication by capsid-targeted virus inactivation

Japanese encephalitis virus (JEV) is a leading member of the mosquito-transmitted flavivirus family, and is mainly distributed in China, India and South East Asia, where it can cause the central nervous system disease with irreversible neurological damage in humans and animals. Few effective anti viral drugs are currently available against JEV infections. To explore the feasibility of using capsid-targeted viral inactivation (CTVI), as an anti viral strategy against JEV infection, a plasmid pcDNA-Cap-SNase was constructed for expressing a fusion protein of JEV capsid (Cap) and Staphylococcus aureus nuclease (SNase). Under G418 selection, a mammalian cell line BHK-21/Cap-SNase stably expressing Cap-SNase fusion proteins could be detected by rabbit antiserum against JEV and had good nuclease activity in degrading DNA or RNA. The viral titer from JEV-infected BHK-21/Cap-SNase cell line was reduced about 69.7% compared with that produced in control BHK-21 cells. It was clearly demonstrated that Cap-SNase fusion proteins could be use to efficiently inhibit JEV replication, resulting in a reduction of viral titer. Therefore, the CTVI approach might be applicable to JEV inhibition as a novel anti viral strategy.