As the latest in a series of studies, researchers at Plymouth University, National Institutes of Health and University of California, Riverside, have shown the ability of a vaccine vector based on a common herpesvirus called cytomegalovirus (CMV) expressing Ebola virus glycoprotein (GP), to provide protection against Ebola virus in the experimental rhesus macaque, non-human primate (NHP) model. Demonstration of protection in the NHP model is regarded as a critical step before translation of Ebola virus vaccines into humans and other great apes.
The study is published today, Monday 15th February, in the online journal from Nature publishing, Scientific Reports.
In addition to establishing the potential for CMV-based vaccines against Ebola virus, these results are exciting from the potential insight they give into the mechanism of protection. Herpesvirus-based vaccines can theoretically be made to produce their targeted protein (in this case, Ebola virus GP) at different times following vaccination. The current CMV vaccine was designed to make the Ebola virus GP at later times. This resulted in the surprising production of high levels of antibodies against Ebola virus with no detectable Ebola-specific T cells. This immunological shift towards antibodies has never been seen before for such primate herpesvirus-based vaccines, where responses are always associated with large T cell responses and poor to no antibodies.
"This finding was complete serendipity," says Dr Michael Jarvis who is leading the project at Plymouth University. "Although we will definitely need to explore this finding further, it suggests that we may be able to bias immunity towards either antibodies or T cells based on the time of target antigen production. This is exciting not just for Ebola, but for vaccination against other infectious as well as non-infectious diseases".
A largely untold story is the devastating effect Ebola virus is having on wild great ape populations in Africa. Although the present study administered the vaccine by direct inoculation, a CMV-based vaccine that can spread from animal to animal may be one approach to protect such inaccessible wild animal populations that are not amenable to vaccination by conventional approaches. The current study is a step forward, not only for conventional Ebola virus vaccines for use in humans, but also in the development of such 'self-disseminating vaccines' to target Ebola in great apes, and other emerging infectious diseases in their wild animal host before they fully establish themselves in humans.
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Link to paper - http://www.nature.com/articles/srep21674
DOI: 10.1038/srep21674
For more information about this news release please contact Andrew Gould, andrew.gould@plymouth.ac.uk
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Plymouth University Peninsula Schools of Medicine and Dentistry (PUPSMD) focuses on medical, dental and biomedical education and research. In education it takes the lead in using innovative, evidence-based learning techniques which nurture future doctors, dentists and biomedical scientists who are clinically excellent, have immense empathy for those in their care, and who are well-prepared for roles in an ever-changing health service. Research covers the areas of clinical neurosciences; cancer; inflammation, infection and immunity; diagnostics; genomics; stratification; prevention; personalised integrated care; and novel health technologies. The Research Excellence Framework 2014 ranked the organisation top in the UK for the quality of its research outputs. It is one of the lead academic partners in the Alzheimer's Research UK South West Research Network, and one of four Research Centres of Excellence for charity Brain Tumour Research. PU PSMD holds the Athena SWAN Bronze Award. The awards recognise institutional and departmental commitment to advancing women's careers in science, technology, engineering, mathematics and medicine/dentistry in Higher Education and Research. The Plymouth University 'Shape the Future' Campaign is a strategic fundraising initiative to transform lives and make a real and lasting difference to our global society. It supports a number of projects including the Derriford Research Facility and Brain Tumour Research at Plymouth University. If you would like to support the Campaign you can find out more by visiting http://www.plymouth.ac.uk/campaign
Journal
Scientific Reports