THURSDAY, May 3, 2007 (HealthDay News) -- U.S. scientists say they've developed a vaccine that protects mice from a brain condition similar to mad cow disease.
Illnesses such as bovine spongiform encephalopathy, or mad cow disease, are caused by infectious prion proteins. There are no treatments or cures for prion diseases, which also include scrapie (often found in sheep), and chronic wasting disease.
Because prions are very similar to proteins produced naturally in the body, the immune system does not attack and destroy them. Prions can be transmitted when an animal eats the body parts of other infected animals.
But the U.S. team said it had created a vaccine that would stimulate the immune system of mice by attaching prion proteins to a genetically modified strain of the salmonella.
The vaccine either prevented or significantly delayed the onset of prion disease symptoms in the mice.
"These are promising findings. We are now in the process of redesigning the vaccine so it can be used on deer and cattle," study author Dr. Thomas Wisniewski, of the New York University School of Medicine, said in a prepared statement.
He noted that much more research is required before the vaccine could be considered for use in people.
"The human version of prion disease usually occurs spontaneously and only rarely because of eating contaminated meat. But if, for example, a more significant outbreak of chronic wasting disease in deer and elk occurs, and if it were transmissible to humans, then we would need a vaccine like this to protect people in hunting areas," Wisniewski said.
The study was expected to be presented this week at the American Academy of Neurology's annual meeting, in Boston.
More information
The U.S. National Institutes of Health has more about prion diseases.
