Collaborative research groups at nine different universities, involving 55 different investigators across Canada, are poised to make significant advances in the understanding of prion and prion-like diseases in humans and animals. These include the development of an oral vaccine to help stop the spread of chronic wasting disease (CWD) in wild deer and elk populations and novel approaches to treat human neurodegenerative disorders like ALS (Lou Gehrig’s disease), Alzheimer’s and Parkinson’s diseases, thanks to $2.9 million in funding announced by PrioNet Canada.
The goal of the funding, which supports 11 projects, is two-fold, explains Dr. Neil Cashman, Scientific Director of PrioNet Canada, one of Canada’s Network of Centres of Excellence. “By working with our partners, we aim to continue to protect Canada against classical prion diseases like chronic wasting disease and mad cow disease (bovine spongiform encephalopathy or BSE), and we’re also providing benefit to Canadians through the development of innovative therapeutics to treat neurodegenerative diseases like Alzheimer’s, Parkinson’s and ALS.”
The researchers will use the funds to better understand the biology of prion disease, to develop strategies to manage prion disease outbreaks and minimize the impacts, and to apply learnings of prion diseases to the treatment of human neurodegenerative disorders.
Prion diseases are fatal, infectious and transmissible diseases of humans and animals associated with a ‘sponge-like’ degeneration of brain tissue. In animals, the most common prion diseases include BSE, scrapie in sheep and goats, and CWD in deer and elk. In 2003, Canada’s beef and related industries were faced with worldwide closing of trade after a domestic case of BSE was found in Alberta. Canada’s economic loss stemming from this event is estimated at more than $6 billion. Some examples of prion diseases in humans include fatal and sporadic familial insomnia, Creutzfeldt-Jakob disease (CJD) and its many varieties, and Kuru.
Some examples of the ground-breaking work supported by PrioNet’s recent funding include:
- Immunotherapies to treat ALS: Five PrioNet researchers at the University of British Columbia,University of Alberta and University of Toronto are focusing on a newly-recognized molecular mechanism of ALS, a misfolded protein called SOD-1. By identifying the parts of the protein that are exposed when it is misfolded in disease, researchers are able to design immunotherapies that can target those areas, interrupting the slow progression of paralysis and eventual death characterized by the disorder. Two animal models have already demonstrated responsiveness to the new immunotherapies and work is now underway to develop a therapy for humans. “We are hoping these discoveries could prove to be a magic bullet for ALS,” said Dr. Cashman, who serves as principal investigator for the multi-disciplinary research team.
- Oral vaccine to control chronic wasting disease in the wild: Prion diseases like chronic wasting disease are continuing to spread throughout the Canadian prairie’s wild deer and elk populations and 10 PrioNet researchers in Saskatoon and British Columbia are working on an oral vaccine to stop the spread. “The danger is that prion diseases are evolving and new strains are emerging,” noted Dr. Scott Napper, a Research Scientist with the Vaccine and Infectious Disease Organization in Saskatoon and principal investigator on the project. Dr. Napper’s group is focusing on an oral vaccine that can withstand extreme temperatures and will effectively attract elk and deer in the wild. Similar oral vaccines are already used to control rabies in Eastern Canada, where food packets containing the vaccine are widely distributed for consumption by fox and raccoon populations.
- Framework to minimize the impact of chronic wasting disease: Principal investigator Dr. Ellen Goddard from the University of Alberta along with nine co-investigators are working to identify the risk factors associated with chronic wasting disease in wild deer and elk populations, how they can be managed and what public policy recommendations should be put in place to try and mitigate the effects. The primary goal is to monitor the many unknowns that remain about the impact of CWD in the wild, such as the potential risk to hunters who consume infected animals and the potential interface between wild and domestic animals. “The risk management framework around BSE showed that even though countries were aware of the disease in their cattle, they completely underestimated the economic impact and the public response,” notes Dr. Goddard. “We’re doing the work ahead of the game while CWD is still manageable and while effective policies can be put into place to control it, to help anticipate and prevent the impacts.”
- Understanding ‘good versus bad’ prions in order to develop drugs: The first step to designing drugs to treat prion and prion-like diseases is to understand how prion proteins change shape when they become “misfolded” in disease. Dr. Christoph Borchers, a Professor in the Department of Biochemistry and Microbiology and Director of the University of Victoria-Genome BC Proteomics Centre is collaborating with researchers from the University of Alberta and University of Western Ontario to characterize the changes that occur to the three-dimensional structure of prion fibrils (small, nerve-like fibres) as well as the molecular mechanisms that lead to those changes. Using a combination of protein chemistry and mass spectrometry, they are working to explain what occurs when a ‘good’ prion protein changes to a ‘bad’ one during disease development. The information is crucial to designing drugs that can interfere with those changes, effectively curbing the spread of prion and prion-like diseases.