Vaccine Prevents Prion Disease In Mice
An oral vaccine can prevent mice from developing a brain disease similar to mad cow disease.
The disease spreads when an animal eats the body parts of other animals contaminated with prions. The disease causes dementia and abnormal limb movements.
Prion is a protein that is also an infectious agent. The proteins are so similar to proteins found normally that the immune system does not fight them off. To develop a vaccine that would stimulate the mice's immune system, researchers attached prion proteins to a genetically modified strain of Salmonella.
For the study, the mice were orally vaccinated with a safe, attenuated Salmonella strain, which expressed the prion protein. Then they were divided into two groups