Infectious Protein Particle Prions

Transmissible spongiform encephalopathies (TSEs), otherwise known as prion disorders, are fatal diseases causing neurodegeneration in a wide range of mammalian hosts, including humans. The causative agent prions are thought to be composed of a rogue isoform of the endogenous prion protein (PrP). Prion diseases or TSEs are a group of rare but fatal neurological disorders that affect humans and animals. Whether sporadic, inherited or acquired, these illnesses generally correlate with the accumulation of misfolded PrP in the brain and the appearance of widespread neurodegeneration after long incubation times. The classical histopathological landmarks of TSEs are spongiform vacuolation, neuronal loss and astrocytic gliosis, whereas the main clinical manifestations in humans include progressive dementia, cerebellar ataxia and myoclonus. Interestingly, although such symptoms are also observed in more common neurodegenerative disorders like Alzheimer's disease (AD) and Parkinson's disease (PD), prion diseases have received special attention because of their infectious nature and the associated risk of epidemics.