title: DNAzyme-mediated inhibition of Japanese encephalitis virus replication in mouse brain.
abstract: Japanese encephalitis virus (JEV) is an arthropod-borne flavivirus with a single-stranded RNA genome containing non-coding regions (NCRs) at its 5' and 3'-ends. The NCRs have flavivirus-conserved sequences that are important for virus replication. Here we describe DNAzymes (Dzs) that cleave the RNA sequence of the 3'-NCR of JEV genome in vitro. The nuclease-resistant Dzs, containing phosphorothioate linkages, were efficiently taken up by mouse neuronal and glial cells, and addition of a continuous stretch of 10 guanosine residues (poly-(G)(10)) to the 3'-end of a Dz led to its enhanced delivery to cells containing scavenger receptors (ScRs). These novel Dzs inhibited JEV replication in cultured mouse cells of neuronal and macrophage origin. JEV is a neurotropic virus that actively replicates in mouse brain. Here we show that intra-cerebral (i.c.) administration of a poly-(G)(10)-tethered, phosphorothioated Dz in JEV-infected mice led to more than 99.99% inhibition of virus replication in brain, resulting in a dose-dependent extended lifespan or complete recovery of the infected animals. This is the first report of in vivo application of a Dz to control a virus infection in an animal model.
authors.affiliation: Virology Laboratory, National Institute of Immunology, New Delhi, India.
authors.forename: Mohan Babu
authors.initials: MB
authors.lastname: Appaiahgari
authors.forename: Sudhanshu
authors.initials: S
authors.lastname: Vrati
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology / Q000821:virology*; D002460:Cell Line; D021881:DNA, Catalytic / Q000008:administration & dosage* / Q000378:metabolism; D004664:Encephalitis Virus, Japanese / Q000235:genetics*; D004672:Encephalitis, Japanese / Q000517:prevention & control / Q000628:therapy / Q000821:virology; D051379:Mice; D011068:Poly G / Q000378:metabolism; D012367:RNA, Viral / Q000378:metabolism; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D021881:DNA, Catalytic; D012367:RNA, Viral; D011068:Poly G