According to an article published in the journal Nature Neuroscience, healthy prions (PrP proteins) have beneficial functions in the nervous system, even more so they are necessary to create a myelin that covers or binds nerves.
At the time of the mad cow crisis, researchers discovered that the disease was caused by distorted prions with lost structure and by Creutzfeldt-Jakob disease, a disease similar to that of people. Prions were associated with diseases.
However, scientists suspected that PrP protein may have some function. Four years ago, the neuropathologist at the University of Zurich, Adriano Aguzzi, focused on a work published by Japanese researchers in 1999, in which it was reported that mice lacking PrP protein were damaged in peripheral nerves.
Aguzzi and his team have continued to investigate this path and have shown that PrP protein is necessary in the mouse so that neurons in the peripheral nervous system meet well with myelin. Without Prp protein, myelin is not complete, so mice develop diseases of the nervous system.
Researchers believe that PrP protein is important in human diseases related to the loss of myelin, such as multiple sclerosis. Therefore, they have expressed their "intention to continue investigating".