Figure 1

Overexpression of GBP1 suppresses PRRSV replication in vitro. A Western blotting verification of Marc-145 cells stably expressing Flag-GBP1. B Immunofluorescence assay identification of Marc-145-Vector and Marc-145-GBP1-flag recombinant cell lines using rabbit anti-GBP1 mAb and Alexa Fluor 488-conjugated goat anti-rabbit IgG (H&L). Marc-145-Vector and Marc-145-GBP1-flag cells were infected with a 0.1 MOI of PRRSV for 24, 36 and 48 h. Cells were harvested for the detection of (C and F) PRRSV ORF7 mRNA expression and viral copy numbers in the supernatant via qPCR, while D protein expression was detected via Western blotting. E Marc-145-Vector and Marc-145-GBP1-flag cells were infected with PRRSV (MOI = 0.1). Infected cells were assessed by incubation with anti-GBP1 and anti-PRRSV N antibodies, followed by incubation with Alexa Fluor 488-conjugated goat anti-rabbit IgG (H&L) and Alexa Fluor 594-conjugated goat anti-mouse IgG (H&L) antibodies, then samples were used for confocal microscopy observation. Porcine alveolar macrophages were inoculated with 2.0 and 5.0 MOI of recombinant lentivirus expressing GBP1 or 5.0 MOI of lenti-Vector for 24 h, followed by infection with 0.1 MOI of PRRSV. At 36 h post-infection, cells were harvested for G GBP1 and PRRSV ORF7 mRNA expression analysis via qPCR, and H for GBP1 and N protein expression analysis via Western blotting. I Supernatants were harvested for progeny viral copy detection via qPCR. GBP1, guanylate-binding protein 1; PRRSV, porcine reproductive and respiratory syndrome virus; ORF, open reading frame; qPCR, quantitative PCR.