Expression of porcine fusion protein IRF7/3(5D) efficiently controls foot-and-mouth disease virus replication.

Abstract

UNLABELLED:

Several studies have demonstrated that the delivery of type I, II, or III interferons (IFNs) by inoculation of a replication-defective human adenovirus 5 (Ad5) vector expressing IFNs can effectively control foot-and-mouth disease (FMD) in cattle and swine during experimental infections. However, relatively high doses are required to achieve protection. In this study, we identified the functional properties of a porcine fusion protein, poIRF7/3(5D), as a biotherapeutic and enhancer of IFN activity against FMD virus (FMDV). We showed that poIRF7/3(5D) is a potent inducer of type I IFNs, including alpha IFN (IFN-α), IFN-β, and IFN-ω but not type III IFN (interleukin-28B), without inducing cytotoxicity. Expression of poIRF7/3(5D) significantly and steadily reduced FMDV titers by up to 6 log10 units in swine and bovine cell lines. Treatment with an IFN receptor inhibitor (B18R) combined with an anti-IFN-α antibody neutralized the antiviral activity in the supernatants of cells transduced with an Ad5 vector expressing poIRF7/3(5D) [Ad5-poIRF7/3(5D)]. However, several transcripts with known antiviral function, including type I IFNs, were still highly upregulated (range of increase, 8-fold to over 500-fold) by poIRF7/3(5D) in the presence of B18R. Furthermore, the sera of mice treated with Ad5-poIRF7/3(5D) showed antiviral activity that was associated with the induction of high levels of IFN-α and resulted in complete protection against FMDV challenge at 6, 24, or 48 h posttreatment. This study highlights for the first time the antiviral potential of Ad5-poIRF7/3(5D) in vitro and in vivo against FMDV.

IMPORTANCE:

FMD remains one of the most devastating diseases that affect livestock worldwide. Effective vaccine formulations are available but are serotype specific and require approximately 7 days before they are able to elicit protective immunity. We have shown that vector-delivered IFN is an option to protect animals against many FMDV serotypes as soon as 24 h and for about 4 days postadministration. Here we demonstrate that delivery of a constitutively active transcription factor that induces the production of endogenous IFNs and potentially other antiviral genes is a viable strategy to protect against FMD.

• Authors: Lisbeth Ramírez-Carvajal, Fayna Díaz-San Segundo, Danielle Hickman, Charles R Long, James Zhu, Luis L Rodríguez, Teresa de los Santos
• Journal: Journal of virology (J Virol) Vol. 88 Issue 19 Pg. 11140-53 (Oct 2014) ISSN: 1098-5514 [Electronic] United States
• PMID: 25031341 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Chemical References

• Interferon Inducers
• Interferon Regulatory Factor-7
• Interferon Type I
• Recombinant Fusion Proteins
• Vaccines, Synthetic
• Viral Proteins
• Viral Vaccines
• B18R protein, Vaccinia virus

Topics

• Adenoviridae (genetics, immunology)
• Animals
• Cattle
• Cell Line
• Foot-and-Mouth Disease (immunology, prevention & control, virology)
• Foot-and-Mouth Disease Virus (genetics, immunology)
• Gene Expression (immunology)
• Genetic Vectors
• Humans
• Interferon Inducers (antagonists & inhibitors, immunology)
• Interferon Regulatory Factor-7 (antagonists & inhibitors, genetics, immunology)
• Interferon Type I (antagonists & inhibitors, biosynthesis, immunology)
• Mice
• Recombinant Fusion Proteins (genetics, immunology)
• Swine
• Vaccination
• Vaccines, Synthetic
• Viral Proteins (pharmacology)
• Viral Vaccines (administration & dosage, immunology)
• Virus Replication (immunology)