STAT2 and viral infectious disease: IKK-ε and TBK1 phosphorylate and activate IFN regulatory factor 3 (IRF3) in response to virus infection, further evoking cellular antiviral responses, including the production of IFN-I.15–17 We found that, in human primary fibroblast cells, VSV strongly induced the phosphorylation of STAT2 on T404, along with that of IRF3 (Fig. 3h), and the same observation was made in HME cells (Supplementary information, Fig. S3i).