CCL4 and viral infectious disease: We therefore stimulated ZFL cells with the three viral antigen NPs and the control iRFPNP and checked expression of innate immune gene markers of viral infection: IFN-stimulated genes (35) including transcription factors irf7 and stat1b and genes encoding antiviral peptides mx and viperin (vig1) (36), as well as gig2 and chemokine ccl4. The viral dsRNA mimic, poly(I:C), was used as a positive control as it mounts an antiviral response in zebrafish (29) among other species, and as such is being tested as a potential fish vaccine adjuvant (37).