Figure 2

Antiviral ability of grass carp IFN1. (A) The pathogenicity of GCRV873 virus particles. The upper bottle contains M199 culture medium supplied with 10% fetal bovine serum; the middle bottle contains M199 culture medium supplied with 10% fetal bovine serum and GCRV873 virus particles at a final concentration of 5.0 × 10⁴ PFU/mL; the lower bottle contains M199 culture medium supplied with 10% fetal bovine serum and GCRV873 virus particles at a final concentration of 5.0 × 10⁵ PFU/mL. (B) The results of crystal violet staining of CIK cells in M199 medium supplied with or without GCRV873 virus particles. 1: CIK cells were infected with GCRV873 (viral titer: 1.0 × 10² PFU/mL); 2: CIK cells were electrically transfected with pCDNA3.1 and infected with GCRV873 (viral titer: 1.0 × 10² PFU/mL); 3: CIK cells were electrically transfected with pCDNA-IFN1-His and infected with GCRV873 (viral titer: 1.0 × 10² PFU/mL); 4: CIK cells were electrically transfected with pCDNA-IFN1-His and not infected with GCRV873. Red arrow: Plaques formed in cultured CIK cells. Yellow arrow: No plaques formed in cultured CIK cells. (C) The transcriptional expression of factors in CIK cells infected with GCRV873 (viral titer: 1.0 × 10² PFU/mL). S5 and S6 are subunits of GCRV873. IFR-9 and STAT1 are key molecules downstream of type I interferon signaling. Data were expressed as mean ± SD. ** p < 0.01; *** p < 0.001.