Mad cow disease research not new to USU scientists

By Denise Albiston

The likelihood of somebody contracting mad cow disease from cattle produced in the United States is approximately zero, according to John Morrey, a Utah State University researcher in the Animal, Dairy and Veterinary Science department.

"The part of the cow that causes variant Creutzfelt-Jakob disease, or vCJD, in humans is the nervous system of the cow, like the brain and spinal cord," said Ken Allen, a senior majoring in biology working at USU's Institute for Antiviral Research.

Research into mad cow disease, or bovine spongiform encephalopathy, has been ongoing at USU long before last December when the United States experienced the nation's first case in Washington State. For the past two years, a team of researchers and students have been experimenting with rodents genetically enhanced to carry a form of the disease, Morrey said.

"We work with mice that are genetically engineered to have the disease in a much shorter time frame. They're genetically engineered to get the disease sooner, within two or three months compared to five months or a year, so we can do more experiments and get results faster," Allen said.

The focus of the experiments, said Justin Julander, a graduate student also employed by the Institute for Antiviral Research at USU, is to investigate different drugs that may treat or have some affect on mice with the disease. Julander said when somebody gets vCJD, "they're going to die, there is no treatment for them." He added that the institute hopes to change that.

"We have not found anything, nor has anybody else in the world -- as far as we know -- found anything or any drugs that can be given therapeutically after the signs of the disease have occurred that are beneficial," Morrey said.

The problem with prion diseases is that there is not a treatment for them, Julander said. He added if an infection occurs, prions will attack the brain causing holes to form and this will unfortunately result in severe neurological damage that is irreversible.

What we're doing is investigating different drugs that may treat the disease, Julander said. As of now, Morrey said, there are some drugs that we can give experimentally to the mice before they are infected that will strongly delay the disease, but nothing to slow it down after the infection has taken place. Biochemically speaking, there is hope, Morrey said. He added, they believe that there is a drug that can help slow the process or even reverse it, they just haven't found it yet.

Morrey said a prion disease is a class of infections in which mad cow disease is only one, there are many others. He added, Chronic Wasting Disease is another form found in elk and deer along with Scrapies being found sheep. Every form of a prion disease is specific to its particular species, there is generally a very strong species barrier that restricts the disease from being passed between different species, Morrey said.

"The fact that people have actually gotten the disease from cows is an anomaly," Morrey said.

Julander said humans can contract vCJD from eating tainted beef, however it could take 20 or 30 years before the signs of the disease become present. He added that it is a strange disease that's not found in the muscle meat of the animal, if meat is taken from an infected cow and feed to a healthy cow the disease is not transmitted.

When the outbreak in Great Britain occurred, the USDA put into force regulations that dramatically reduced the chances of a mad cow disease epidemic in the United States, Morrey said. What's happened are the animals that have been found to be infected here recently were alive before these regulations went into action.

"My gut feeling is that food is safe, and that we've really nipped this in the bud," Morrey said.

After the outbreak of mad cow disease in Great Britain, the National Institute of Health began funding USU's research into mad cow disease in anticipation of a possible outbreak, said Morrey. He added that so far there hasn't been one, but the research is a preventative measure to understand and protect people from the disease.

The research with mad cow disease at USU has been entirely funded by a grant from the National Institute of Health which is also funding a host of other experiments at USU's Institute for Antiviral Research, Morrey said. He added that this grant has provided excellent opportunities for the school, including a large amount of money. There are many other advantages that are sometimes overlooked, like the extraordinary opportunity for students to work in this research environment, and the possibility of contributing to the body of knowledge on prion disease that will increase the credibility of the school, Morrey said.

Many different research projects are being hosted at USU, and it is important to remember that it is a real "team effort," said Robert Sidwell, director of USU's Institute for Antiviral Research.

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