Delayed Newcastle disease virus replication using lentiviral facilitated RNA interference to target the nucleoprotein

Each year millions of chickens die from Newcastle disease virus (NDV) worldwide leading to economic and food losses. Current vaccination campaigns have limitations including cost, administration, and thermostability. These problems are heightened in the developing world where constraints are more rigid, thus leading to interest in producing new antiviral strategies. RNA interference (RNAi) methodology is capable of inhibiting viral replication in vitro and in vivo. In this study, we utilize an RNAi strategy that produces microRNA (miRNA) targeting and knocking down NDVs nucleoprotein (NP), phosphoprotein (P), matrix (M), fusion (F), and large (L) proteins. NDV challenged chicken embryo fibroblast cells (DF-1) cells transfected with miRNA targeting NP resulted in observable delay of NDV replication in culture as determined by increased cell survival. Subsequently transduced NP cells exposed to viral challenge demonstrated improved cell survival up to 48 hours post infection (h.p.i) and decreased viral shedding in culture up to 72h.p.i.