title: Synergic and antagonistic effect of small hairpin RNAs targeting the NS gene of the influenza A virus in cells and mice.
abstract: In the present study, we demonstrate the effect of individual and mixtures of shRNAs targeting the NS gene to treat an established infection of influenza A virus (IAV). We prepared 10 shRNAs targeting the NS gene of the IAV, and these shRNAs were tested individually or in mixtures 16h after infection. Our results revealed: (i) shRNA targeting the NS1 transcript decreased the virus titre up to 21% (P<0.01), (ii) shRNA targeting NEP transcript did not influence the replication of IAV in the infected cells; (iii) a mixture of shRNAs targeting the NS1 transcript was less effective than the individual shRNAs and decreased the virus titre up to 42% in vitro; (iv) a mixture of individually inactive shRNAs targeting the NEP transcript significantly inhibited the replication of IAV in vitro; (v) the activities of the individual shRNAs in vivo predominantly corresponded to their activities in vitro; (vi) a synergistic effect of the shRNAs was observed in vivo; and (vii) a shRNA targeting the region common to both the NS1 and NEP transcripts, shNS593, exhibited the strongest inhibition and reduced the virus titre up to 16.4% in vitro, prolonged the survival of the mice by three days and abolished the protective effect of other shRNAs in vivo. shRNAs inhibited influenza virus infection in a gene-specific manner. NS1 mRNA was significantly reduced in lungs treated with shRNAs and the levels of RIG-1, IFN-α, IFN-β and IFN-γ mRNAs shRNAs were not altered.
authors.affiliation: Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, 845 05 Bratislava, Slovak Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Svancarova
authors.affiliation: Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, 845 05 Bratislava, Slovak Republic.
authors.forename: Darina
authors.initials: D
authors.lastname: Svetlikova
authors.affiliation: Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, 845 05 Bratislava, Slovak Republic; Centre for Molecular Medicine, Vlarska 3-7, 831 01 Bratislava, Slovak Republic. Electronic address: virubeta@savba.sk.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Betakova
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage / Q000378:metabolism*; D004357:Drug Synergism; D005260:Female; D009980:Influenza A virus / Q000187:drug effects* / Q000502:physiology; D008168:Lung / Q000473:pathology / Q000821:virology; D008807:Mice, Inbred BALB C; D009976:Orthomyxoviridae Infections / Q000188:drug therapy* / Q000821:virology; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism*; D016019:Survival Analysis; D016896:Treatment Outcome; D019562:Viral Load; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; C108309:NS protein, influenza virus; D034741:RNA, Small Interfering; D017361:Viral Nonstructural Proteins
keywords: Influenza virus; NEP protein; NS1 protein; shRNA