- OMAHA, Neb. -- Proteins that may cause "mad cow" disease,
chronic wasting disease in mule deer and elk, and Creutzfeldt Jakob disease
in humans, all of which are fatal neurological diseases, are the subject
of two studies at Creighton funded by federal grants.
- Richard Bessen, assistant professor of
medical microbiology and immunology, has received a five-year $488,000
National Institutes of Health grant and a three-year $250,000 grant from
the United States Department of Agriculture to study prions.
- Prions are proteins that all humans possess
in their normal form. The disease forms are chemically identical but are
configured in different shapes.
- "What makes prions unique is that
these infectious agents do not appear to contain a nucleic acid molecule
which is the genetic basis of all life forms," Bessen said. "Prion
diseases are caused by the misfolding of normal prion proteins. There is
debate about how this misfolding occurs and how that pattern is replicated."
- It appears that "mad cow" disease,
or bovine spongiform encephalopathy (BSE), adapted from sheep scrapie.
- "If you eat processed foods, such
as sausage or products with animal-derived food additives, you may have
been exposed to sheep scrapie, with no effect," Bessen said. "However,
cattle apparently are susceptible upon oral exposure to scrapie-contaminated
feed additives. Once they infected cattle, the prions may have adapted
further to create an agent that posed danger to humans.
- "The BSE epidemic in the United
Kingdom indicates that these agents, transmissible spongiform encephalopathies
or TSEs, can adapt unpredictably to new hosts and potentially can cause
widespread neurodegenerative disease," Bessen said. "There have
been more than 175,000 cases of BSE in Europe, mainly in the United Kingdom."
- Initially, the potential danger of BSE
to humans was downplayed, but BSE now has been linked to 27 cases of variant
Creutzfeldt-Jakob disease in humans. The cattle industry has changed feeding
and herd management approaches to avoid possible transmission of prion
disease to humans and animals. No cases of BSE have been confirmed in the
- Bessen is examining the molecular basis
of prion strain diversity and how prions replicate. He also will investigate
the ability of drugs to inhibit the conversion of normal prions into the
- Creighton is an independent Catholic
university operated by the Jesuits. It recently was ranked No. 1 for the
third consecutive year among Midwestern universities in the U.S. News and
World Report magazine's 1999 "America's Best Colleges" edition.
- Creighton enrolls approximately 6,200
students in the Colleges of Arts and Sciences and Business Administration,
the Graduate School, University College and schools of Nursing, Medicine,
Law, Pharmacy and Allied Health Professions, Dentistry, and Summer Sessions.