TRAF3 and infection: CRISPR-Cas9 gene-editing technology was used to construct TRAF3-knockout MDCK cells (MDCK-TRAF3-/-), and after IVA infection, the HA titre and viral titre of MDCK-TRAF3-/- cells were elevated, the type I interferon-related pathway was significantly blocked, and the transcription of several antiviral-related genes was significantly reduced; therefore, the knockout of the TRAF3 gene decreased the resistance of MDCK cells to IVA, thus providing a prospective research field for improving IVA isolation and influenza vaccine production [33].