title: siRNAs targeting PB2 and NP genes potentially inhibit replication of Highly Pathogenic H5N1 Avian Influenza Virus.
abstract: Highly Pathogenic Avian Influenza (HPAI) H5N1 virus is a threat to animal and public health worldwide. Till date, the H5N1 virus has claimed 402 human lives, with a mortality rate of 58 percent and has caused the death or culling of millions of poultry since 2003. In this study, we have designed three siRNAs (PB2-2235, PB2-479 and NP-865) targeting PB2 and NP genes of avian influenza virus and evaluated their potential, measured by hemagglutination (HA), plaque reduction and Real time RT-PCR assay, in inhibiting H5N1 virus (A/chicken/Navapur/7972/2006) replication in MDCK cells. The siRNAs caused 8- to 16-fold reduction in virus HA titers at 24 h after challenged with 100TCID50 of virus. Among these siRNAs, PB2-2235 offered the highest inhibition of virus replication with 16-fold reduction in virus HA titer, 80 percent reduction in viral plaque counts and 94 percent inhibition in expression of specific RNA at 24 h. The other two siRNAs had 68-73 percent and 87-88 percent reduction in viral plaque counts and RNA copy number, respectively. The effect of siRNA on H5N1 virus replication continued till 48h (maximum observation period). These findings suggest that PB2-2235 could efficiently inhibit HPAI H5N1 virus replication.
authors.affiliation: ICAR-National Institute of High Security Animal Diseases, Bhopal 462 022, India.
authors.forename: Padmanava
authors.initials: P
authors.lastname: Behera
authors.forename: Shanmugasundaram
authors.initials: S
authors.lastname: Nagarajan
authors.forename: Harshad V
authors.initials: HV
authors.lastname: Murugkar
authors.forename: Semmannan
authors.initials: S
authors.lastname: Kalaiyarasu
authors.forename: Anil
authors.initials: A
authors.lastname: Prakash
authors.forename: Ragini
authors.initials: R
authors.lastname: Gothalwal
authors.forename: Shiv Chandra
authors.initials: SC
authors.lastname: Dubey
authors.forename: Diwakar D
authors.initials: DD
authors.lastname: Kulkarni
authors.forename: Chakradhar
authors.initials: C
authors.lastname: Tosh
mesh_terms: D000818:Animals; D002460:Cell Line; D002645:Chickens / Q000821:virology; D004285:Dogs; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000235:genetics*; D005585:Influenza in Birds / Q000188:drug therapy / Q000821:virology; D007251:Influenza, Human / Q000188:drug therapy / Q000821:virology; D061985:Madin Darby Canine Kidney Cells; D008826:Microbial Sensitivity Tests; D019590:Nucleocapsid Proteins; D034741:RNA, Small Interfering / Q000235:genetics* / Q000627:therapeutic use; D016601:RNA-Binding Proteins / Q000235:genetics*; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics*; D014758:Viral Core Proteins / Q000235:genetics*; D014764:Viral Proteins / Q000235:genetics*; D014779:Virus Replication / Q000235:genetics*
chemical_list: C048842:NP protein, Influenza A virus; D019590:Nucleocapsid Proteins; C057027:PB2 protein, Influenzavirus A; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D014758:Viral Core Proteins; D014764:Viral Proteins; D012324:RNA-Dependent RNA Polymerase