October 16, 2013
by Coleman Cornelius
What does chronic wasting disease - a killer neurological disease in deer, elk, and moose - have in common with human brain disorders, such as Alzheimer's and Parkinson's disease?
The diseases are caused by protein misfolding that starts a degenerative chain reaction in the nervous system, ultimately leading to death. In the case of chronic wasting disease (CWD), a distorted protein called a prion triggers the neurodegeneration.
The mysteries and fatal effects of prions, as well as the insights they hold for well-known neurological diseases in people, are the focus of a three-day scientific meeting called “Expanding Prion Horizons” at Colorado State University this week. The Prion Research Center, a CSU Program of Research and Scholarly Excellence, is hosting the conference.
CSU researchers have investigated the puzzling properties of prions for decades, since they first identified CWD in deer in northern Colorado, and this week they will host national and international colleagues to consider new scientific questions related to these rogue proteins. This includes what scientists might learn from prion diseases to better understand protein misfolding disorders in people, including Alzheimer’s, Parkinson’s, Lou Gehrig's and Huntington’s diseases.
Nobel laureate Dr. Stanley Prusiner, director of the Institute for Neurodegenerative Diseases at the University of California – San Francisco, will headline the meeting. His keynote talk, “A Unifying Role for Prions in Neurodegenerative Diseases,” will start at 8 a.m. Thursday at the University Center for the Arts. It is free and open to the public.
“It’s an honor to have Dr. Prusiner visit CSU,” said Sue VandeWoude, associate dean for research in the CSU College of Veterinary Medicine and Biomedical Sciences. “Participation of a scientist of his caliber in this conference highlights the decades-long research focus on prion diseases in Fort Collins, and puts the spotlight on CSU as a leader in this intriguing research area.”
Prusiner, a neurologist and biochemist, won the Nobel Prize in Physiology or Medicine in 1997 for prion research. He is credited with first proposing that misfolded proteins with infectious properties cause the family of degenerative neurological diseases now known as prion diseases, or transmissible spongiform encephalopathies.
Prion diseases include: chronic wasting disease, which affects deer, elk, and moose; bovine spongiform encephalopathy, or mad cow disease; scrapie, which affects sheep; and Creutzfeldt-Jakob disease, the fatal prion disorder seen in humans.
Prusiner labored in the laboratory for years to prove that these degenerative diseases are caused by infectious proteins, not by a virus, as scientists widely believed for many years. The maverick scientist even gave the infectious agents their name: prions, from “proteinaceous infectious particles.”
These agents, Prusiner showed, can arise spontaneously, can be inherited, can be transmitted like other infectious pathogens – and can cause other proteins to change shape. The “prion paradigm,” used to describe the activity of these misfolded proteins, since has formed a basis for better understanding other neurodegenerative diseases that plague people, and has led to Prusiner’s investigation of novel therapies to stop neurodegeneration.
“Dr. Prusiner provides us with a compelling story about the emergence of a new scientific paradigm and the importance of basic scientific research,” said Glenn Telling, director of the CSU Prion Research Center.
Prion investigators at CSU are themselves internationally recognized for their expertise in transmissible spongiform encephalopathies that pose a risk for human and animal health. In fact, CSU scientists first identified CWD as a fatal wasting syndrome in mule deer, and then discovered it is a prion disorder.
CWD “continues to spread with alarming efficiency among wild and captive animals” and continues to demand scientific attention, Telling said. Mad-cow disease prions have clearly caused a new form of prion disease in humans, while there is conflicting scientific evidence about the risks that CWD prions pose to people.
This remains an important issue for CSU prion researchers working in the endemic region, where CWD infection rates reach 15 percent to 20 percent in some wild elk and deer populations, Telling said. CWD has spread from its epicenter in northern Colorado to at least 20 other states, two Canadian provinces, and South Korea, scientific surveillance has found.
“This is an emerging epidemic,” Telling said. “CWD is the only recognized prion disease in wild animals, which means it’s very difficult to control, and it’s extremely contagious. It’s important that we understand prion diseases so we can better assess risk to public health.”