Depletion of elongation initiation factor 4E binding proteins by CRISPR/Cas9 enhances the antiviral response in porcine cells

Type I interferons (IFNs) are key mediators of the innate antiviral response in mammalian cells. Elongation initiation factor 4E binding proteins (4E-BPs) are translational controllers of interferon regulatory factor 7 (IRF-7), the master regulator of IFN transcription. Previous studies have suggested that mouse cells depleted of 4E-BPs are more sensitive to IFN beta treatment and had lower viral loads as compared to wild type (WT) cells. However, such approach has not been tested as an antiviral strategy in livestock species. In this study, we tested the antiviral activity of porcine cells depleted of 4E-BP1 by a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein-9 nuclease (Cas9) genome engineering system. We found that 4E-BPI knockout (MO) porcine cells had increased expression of IFN alpha and beta, IFN stimulated genes, and significant reduction in vesicular stomatitis virus titer as compare to WT cells. No phenotypical changes associated with CRISPR/Cas9 manipulation were observed in 4E-BPI MO cells. This work highlights the use of the CRISPR/Cas9 system to enhance the antiviral response in porcine cells. (C) 2015 Elsevier B.V. All rights reserved.