A team of scientists with the Prion Research Laboratory in Colorado State University’s College of Veterinary Medicine and Biomedical Sciences has been awarded a grant of $8.4 million over seven years to study Chronic Wasting Disease including its mode of transmission, the potential for inter-species transmission and a possible vaccine against the disease.
Awarded by the National Institutes of Health, the research study will focus on four major objectives:
- To assess how CWD is transmitted among deer
- To develop a transgenic mouse model for CWD
- To evaluate the potential for inter-species transmission of CWD
- To test potential strategies for a CWD vaccine
Dr. Edward Hoover, Colorado State University Distinguished Professor and director of the laboratory, acknowledged that the objectives of the research are very ambitious, but that he and his collaborators are looking forward to the challenge.
"Progress in the study of this disease has been difficult because the causative agent is a protein rather than a nucleic acid-containing agent," Hoover said. "Therefore, we can’t use the kind of technology we use to detect and understand viruses and bacteria."
"Additionally, the incubation period is quite long-probably two to six years in nature. For this reason, we are working with Dr. Glenn Telling at the University of Kentucky to develop a transgenic mouse model to more easily study the pathogenesis, transmission and intervention of CWD."
The team will also focus on detecting the CWD prion in body fluids and excretions of deer since, as Hoover explained, one of the most interesting and important aspects of the disease is how the infection is transmitted among deer.
Perhaps the most daunting aspect of the research is assessing the potential for development of a vaccine. Since prions are thought to generate an immune response, a vaccine would seem to be out of the question. However, Hoover noted that evidence from some Alzheimer’s’ studies may offer some hope.
"Immunization against the Alzheimer-related protein, amyloid plaques, that accumulate in the brain in some mouse models can prolong survival," Hoover said. "CWD research may therefore yield findings important to human as well as animal prion infections. It is a scientific long shot, and will take years because it is a long, slowly developing infection, but we think it is worth pursuing. We hope that our research will be important to deer and to humans."
Chronic Wasting Disease was first detected in the early 1980s and is endemic in free-ranging deer and elk in northeastern Colorado and southeastern Wyoming. More recently, the disease has emerged as a threat to ranched elk in several western states and has been found in the Midwest in areas of Wisconsin. It is one form of a group of fatal brain diseases called transmissible spongiform encephalopathies, or TSEs, which include Bovine Spongiform Encephalopathy in cattle and Creutzfeldt-Jakob disease in humans.
To date there is no evidence that CWD is transmissible to humans.