Inhibiting avian influenza virus shedding using a novel RNAi antiviral vector technology: proof of concept in an avian cell model

Lyndsey M Linke; Jeffrey Wilusz; Kristy L Pabilonia; Johannes Fruehauf; Roberta Magnuson; Francisco Olea-Popelka; Joni Triantis; Gabriele Landolt; Mo Salman

doi:10.1186/s13568-016-0187-y

Inhibiting avian influenza virus shedding using a novel RNAi antiviral vector technology: proof of concept in an avian cell model

AMB Express. 2016 Mar;6(1):16. doi: 10.1186/s13568-016-0187-y. Epub 2016 Feb 24.

Authors

Lyndsey M Linke^{1

2}, Jeffrey Wilusz³, Kristy L Pabilonia^{4

3}, Johannes Fruehauf⁵, Roberta Magnuson^{4

6}, Francisco Olea-Popelka⁶, Joni Triantis^{4

6

7}, Gabriele Landolt⁶, Mo Salman^{4

6}

Affiliations

¹ Animal Population Health Institute, Colorado State University, Fort Collins, CO, USA. Lyndsey.Linke@colostate.edu.
² Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA. Lyndsey.Linke@colostate.edu.
³ Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA.
⁴ Animal Population Health Institute, Colorado State University, Fort Collins, CO, USA.
⁵ Cambridge Biolabs, Cambridge, MA, USA.
⁶ Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA.
⁷ Environmental Health Services, Colorado State University, Fort Collins, CO, USA.

Abstract

Influenza A viruses pose significant health and economic threats to humans and animals. Outbreaks of avian influenza virus (AIV) are a liability to the poultry industry and increase the risk for transmission to humans. There are limitations to using the AIV vaccine in poultry, creating barriers to controlling outbreaks and a need for alternative effective control measures. Application of RNA interference (RNAi) techniques hold potential; however, the delivery of RNAi-mediating agents is a well-known obstacle to harnessing its clinical application. We introduce a novel antiviral approach using bacterial vectors that target avian mucosal epithelial cells and deliver (small interfering RNA) siRNAs against two AIV genes, nucleoprotein (NP) and polymerase acidic protein (PA). Using a red fluorescent reporter, we first demonstrated vector delivery and intracellular expression in avian epithelial cells. Subsequently, we demonstrated significant reductions in AIV shedding when applying these anti-AIV vectors prophylactically. These antiviral vectors provided up to a 10,000-fold reduction in viral titers shed, demonstrating in vitro proof-of-concept for using these novel anti-AIV vectors to inhibit AIV shedding. Our results indicate this siRNA vector technology could represent a scalable and clinically applicable antiviral technology for avian and human influenza and a prototype for RNAi-based vectors against other viruses.

Keywords: Avian influenza; Bacterial vector; Influenza antiviral; Transkingdom RNAi; siRNA delivery.