To determine whether miR-221-5p inhibits PEDV replication through activation of the innate immune response, we measured the expression of cytokines, such as IFNs, and IFN-stimulated genes (ISGs), such as MX1 and ISG15. Real-time qRT-PCR analysis following miR-221-5p transfection during PEDV infection revealed that miR-221-5p enhanced cytokine and ISG expression during CH/HBTS/2016 infection (Figure 5A), thereby suggesting a role for miR-221-5p in regulating the innate immune response. This evidence concerns the gene MX1 and infection.