Prions and neuro degenerative diseases

Abstract

Prion is a disease-causing agent that is neither bacterial nor fungal nor viral and contains no genetic material. A prion is a protein that occurs normally in a harmless form. By folding into an aberrant shape, the normal prion turns into a rogue agent. It then co-opts other normal prions to become rogue prions. Prions have been held responsible for a number of degenerative brain diseases, including scrapie (a fatal disease of sheep and goats), mad cow disease, Creutzfeldt-Jacob disease, fatal familial insomnia, kuru, an unusual form of hereditary dementia known as Gertsmann-Straeussler-Scheinker disease, chronic wasting disease in deer and elk, bovine spongiform encephalopathy (BSE, commonly known as “mad-cow” disease), exotic ungulate spongiform encephalopathy, Transmissible Mink Encephalopathy (TME), and feline spongiform encephalopathy, albino tigers, pumas, and cheetahs. Currently, definite diagnosis of prion diseases is still considered to be possible only after histopathological examination of biopsied or autopsied brain material. Prion diseases do not stimulate immunity. Therefore, a vaccine that prevents them is unlikely. No treatment is available either, although research in this area is progressing.

Key words: Prion, transmissible spongiform encephalopathies, diagnosis, treatment.