Other studies have shown it may be feasible to recruit the immune system to fight prion-related disease. But the new study, published in the July issue of the American Journal of Pathology, is the first to show a vaccine can delay symptoms in a natural model of prion disease in mice, according to the NYU researchers.

Mad cow disease belongs to a group of fatal diseases called transmissible spongiform encephalopathies. These diseases are characterized by progressive dementia and abnormal limb movements and affect people as well as animals. Prions cause mad cow disease in cattle and scrapie in sheep. Humans can get a number of different prion diseases, including variant Creutzfeldt-Jakob disease (vCJD).

The vaccine approach presented in the new study may be more easily applied to animals, such as cattle, at risk for developing prion disease, than to humans, according to the NYU researchers.

The vaccine in the study is based on the normal sequence of amino acids for the prion protein, which could potentially be toxic if used in humans, explains Einar Sigurdsson, Ph.D., Assistant Professor of Psychiatry and Pathology, an author of the paper. "We are currently making alterations in the prion protein to reduce the likelihood of toxicity while maintaining a therapeutic effect," says Dr. Sigurdsson.

Many scientists believe that the transmissible spongiform encephalopathies are caused by prions, unusual infectious proteins, but it isn't known exactly how the deadly particles kill brain tissue, producing sponge-like holes in the brain. It is known that prions turn deadly by changing their shape. Normal prion protein is present through
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Contact: Pam McDonnell
Pamela.McDonnell@med.nyu.edu
212-404-3555
New York University Medical Center and School of Medicine
2-Jul-2002