IFIH1 and infection: More importantly, the expression and phosphorylation levels of CiIRF3 and CiIRF7 are higher in MDA5+ and RIG-I+ cells than those in EGFP+ cells under GCRV infection or poly(I:C) stimulation (Figure 6), indicating that the immunostimulation but not the expression of immune-related genes is the key to initiate immune responses.