Fig. 4.

The 16-5A mutant induces higher level of type I IFN mRNAs. Porcine monocyte- derived macrophages were mock-infected/infected with 1 MOI of 16-5A mutant or wt FL12 virus. Total RNA isolated from cells was reverse transcribed and real time PCR was done for detection of porcine IFN-α (A), IFN-β (B) mRNA. The mRNA copy numbers were calculated after normalization with porcine β-actin copy number and expressed relative to mock control. Bars show average of mRNA copy numbers±SEM from three independent experiments (‘^⁎’ indicates p<0.05). (C) MARC-145 cells infected with 16-5A/wt virus and 12 h post-infection were super-infected with sendai virus (SeV) 50 HA (hemagglutinating) Units/ml to induce IFN synthesis for another 12 h. ISG56 protein level was detected by immunoblotting. The β-actin served as loading control.