Mad cow disease is a fatal brain disease found in cattle. The disease causes deterioration of the brain and ultimately results in death. Humans could develop the human form of the disease by eating beef contaminated with central nervous system tissues of infected cattle. There currently is no cure for the disease due to the lack of information on the unusual proteins that cause the infection, known as prions. However, a similar disease has recently been vaccinated in deer.
Image source: Image Source
Researchers have developed a vaccination for chronic wasting disease (CWD) in deer. CWD is similar to mad cow disease in that both are caused by infectious proteins known as prions. Prions cause normal proteins primarily located on the surface of central nervous system cells to fold abnormally, resulting in the deterioration of neural tissue. The researchers developed the vaccine by placing a prion-like protein into the genome of a harmless Salmonella bacterium. The result was an immune response by the Salmonella bacteria that led to the production of anti-prion antibodies. The decision to select Salmonella bacteria was based on the bacteria’s ability to easily enter the gut and the fact that the most common method of infection is through the ingestion of prion-contaminated food.
The researchers gave the vaccine to five deer and a placebo to six deer; all of the deer were constantly exposed to the infectious prions. Two years later, all of the deer given the placebo were infected while four of the vaccinated deer took significantly longer to become infected. The fifth vaccinated deer has yet to become infected.
The successful vaccination against CWD may serve as a method to prevent livestock in the U.S. from contracting prion diseases. The researchers believe their results could also extend to treating human diseases believed to be caused by prion infections, such as the human form of mad cow disease, or Creutzfeldt-Jakob disease.
Feature Image Source: cow by ramendan