Although we always observed a clear decrease in IFNβ secretion upon infection with IAV in A549 OTUB1-KO cells as compared with WT cells (black bars in Fig 7F), the secreted IFNβ levels remained high in OTUB1 knockout cells which were transfected with Poly (I:C) (black bars in Fig 7E). Here, OTUB1 is linked to infection.