The Pirbright and Roslin Institutes funded to create a Marek’s Disease vaccine


The Pirbright Institute has recently been awarded joint funding with The Roslin Institute to research how the deadly Mareks disease virus (MDV) causes tumours in poultry, and create a more effective vaccine.
MDV is highly contagious and is a major threat to the poultry industry, with losses estimated to be up to $2 billion worldwide. Nearly 22 billion vaccine doses a year are used in an attempt to control the disease, but the virus continues to evolve and form increasingly virulent strains.
The funding, awarded by the Biotechnology and Biological Sciences Research Council, will allow the Pirbright and Roslin researchers to understand the pathways involved in tumour creation during MDV infection.
Dr Yongxiu Yao, leader of the research, said: “By using the CRISPR/Cas9 gene editing system we intend to disrupt the gene for a virus protein called Meq, which previous data has suggested is a tumour inducing factor. By editing the Meq gene and disrupting its binding with other proteins, we will be able to have a clearer understanding of the pathways involved in tumour formation, which will help us to create better vaccines.”

The modifications to the virus that the Pirbright team makes will be analysed by Roslin researchers to identify the major pathways that are most essential for tumour production and indicate the best targets for future vaccines.
The evolution of highly virulent MDV strains has proven extremely problematic for the poultry industry, as many of the vaccines currently used do not induce sufficient protection against infection. The scientists will therefore investigate Meq’s role in a highly virulent strain and will attempt to reduce its virulence by deleting and swapping the Meq gene. If the alteration of the Meq gene in these strains is successful, it could pave the way for a new vaccine that is able to protect against the most destructive strains of MDV. This in turn would improve poultry welfare and cut losses to the poultry industry.