Antiviral Activity of Specific siRNA against Hemagglutinin and Neuraminidase of Influenza Virus H1N1 in MDCK Cell Culture

Abstract

H1N1 influenza virus causes respiratory syndrome on the upper respiratory system. Hemagglutinin (HA) and Neuraminidase (NA) proteins are the most important viral proteins that play a role in attachment and facilitates of releasing virus respectively. Short interfering RNA (siRNA) plays notable a roles in the RNA interference (RNAi) pathway and interferes the expression of specific genes with complementary nucleotide sequences by breaking down mRNA function and stopping transcription and translation. To explore shutting down HA and NA, siRNA were designed and genes of H1N1 are inhibited by siRNA molecules in MDCK cell culture. The cells were infected with virus and then treated by different concentration of siRNA. The HA, NA gene expression and the viral load were investigated by Real Time PCR between 24 to 72 hours. The cells were infected with H1N1 virus at a multiplicity of infection (MOI: 3) and then treated with different concentration of siRNA (0.5-6 nmol/L) and monitored for 72 hours post transfection. Interestingly, the viral load extremely decreased at first hours, even the viral load was not detectable after 48 hours. Three nmol/L concentration of siRNA for HA was more effective. In case of siRNA for NA, 3 nmol/L concentrations shows efficacy and also cytopathic effect (CPE) was not observed in 3 nmol/L concentrations in MDCK cells. This study suggests that siRNA against NA and HA, silenced viral genes in H1N1 influenza virus infected cells. Results showed that siRNA is an efficient tool for silencing influenza virus infection. The advantage of siRNA is the specific inhibition of mRNA which can be used for inhibition of other flu viral genes and/or other viruses.