Chronic wasting disease as a model for human prion therapy.

Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative disorders that result from abnormally folded prion proteins. These disorders can be sporadic, acquired, or genetic. Acquired TSEs can be found in a number of animal species including sheep (scrapie), cows (bovine spongiform encephalopathy), and cervids (chronic wasting disease). Chronic wasting disease (CWD) is unusual in that it is found in free ranging animals in their natural environment. There has been heretofore no reported cases of CWD being transmitted to humans; however, the possibility of future adaption for human transmission exists. Several novel approaches for the prevention and treatment of prion disease in humans are under development, including knockdown of endogenous prion expression or overexpression of dominant negative prion forms. Here, I propose that CWD, as a naturally occurring prion disease, should be considered an important testing target for such therapies, which can demonstrate efficacy outside of controlled laboratory environments. Further, from the ethical standpoint of reducing animal suffering, decreasing the CWD burden in cervid populations is highly desirable. Finally, lowering CWD incidence can reduce future possibilities of transmission to humans or to other animal species.