Vaccines & Vaccination

Biography

Biography: Mark Fife

Abstract

Type I interferon protect cells from viral infections through the induction of a group of genes collectively named interferon-stimulated genes (ISGs). Among these ISGs, are the IFITM (interferon-inducible transmembrane) which have been shown to restrict the replication of several highly pathogenic human viruses, including severe acute respiratory syndrome (SARS) coronavirus, filoviruses (Marburg virus and Ebola virus), influenza A viruses (IAVs), and flaviviruses (dengue virus). The genetics and genomics group have identified these antiviral proteins in the chicken (chIFITM) and have shown that a reduction in chIFITM expression results in an increase in the virus titre in CEFs infected with avian influenza A virus (AIV) H9N2, suggesting that chIFITMs have a functional role in the control of viral infections. The observation may have useful implications in terms of vaccine production. Many vaccines are produced in embryonated hen’s eggs or continuous avian cell lines. However, it is well established that the rate determining step in the manufacture of numerous vaccines is the induction of antiviral immune responses that prevents the replication of vaccine viruses. To generate chIFITM knock-down, we will use cutting edge genetic approaches such the CRISPR/Cas9 system which will directly target and knock-out chIFITM expression. We believe that this approach will overcome the rate limiting step in vaccine production, directly resulting in increased vaccine yields and improve the speed at which vaccines can be manufactured. We are currently in talks with major vaccine producers keen to adopt this internationally patented technology, to advance the field of both animal and human vaccine production. This work is being conducted in partnership with Horizon Discovery, using their extensive expertise in genetic modification using gene editing technologies. The broad objective of the project is to observe the effect the knock-out of chIFITM genes expression, achieved via CRIPSR/Cas9 transfection methods, has on viral titre in avian cell lines (commonly used for vaccine production) infected with influenza A virus. In addition, through analyzing the genetic material of a wide variety of chicken breeds and outlying avian species that differ in levels of resistance to these viruses, we hope to identify versions of these proteins that give protection, in laboratory, commercial and “backyard” chickens. Analysis of these proteins in the chicken presents opportunities not just for a greater understanding of viral resistance, but also as tools to combat viruses in the poultry farming. It may be feasible to selectively breed for birds with improved resilience to viral infections; however, this requires the identification of resistance-associated factors and knowledge of how they act.