Western Blot Analysis of Viral Proteins

The Western blot assay was carried out as previously described [36 (link)]. In brief, the lysates of PSV-infected PK15 cells and MBP-tagged recombinant VP1 protein were separated on SDS-PAGE gel and transferred to PVDF membranes. Membranes were incubated with either an mAb against VP1 protein (1:200), an anti-MBP mAb (1:10,000), or swine serum (1:100). Secondary antibodies were used with the IRDye 680 conjugated goat anti-mouse IgG (Li-Cor Biosciences, Lincoln, NE, USA) or goat anti-pig IgG (Biodragon-immunotech, Beijing, China) at a dilution of 1:10,000. Finally, membranes were scanned by an Odyssey infrared imaging system (Li-Cor Biosciences).