Preface and Introduction
Takashi Onodera and Akikazu Sakud
from: Prions: Current Progress in Advanced Research (Edited by: Akikazu Sakudo and Takashi Onodera). Caister Academic Press, U.K. (2013)
Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal neurological diseases that include Creutzfeldt-Jakob Disease (CJD) in humans, scrapie in sheep and goats, bovine spongiform encephalopathy (BSE) in cattle, and chronic wasting disease (CWD) in cervids. A key event in prion diseases is the conversion of the cellular, host-encoded prion protein (PrPC) to its abnormal isoform (PrPSc) predominantly in the central nervous system of the infected host (Aguzzi et al. 2004).The diseases are transmissible under some circumstances, but unlike other transmissible disorders, prion diseases can also be caused by mutations in the host gene. The mechanism of prion spread among sheep and goats that develop natural scrapie is unknown. CWD, transmissible mink encephalopathy (TME), BSE, feline spongiform encephalopathy (FSE), and exotic ungulate encephalopathy (EUE) are all thought to occur after the consumption of prion-infected material. Most cases of human prion disease occur from unknown reasons, and >20 mutation in the prion gene may lead to inherited prion disease. In other instances, prion diseases are contracted by exposure to prion infectivity. This raises the question of how a mere protein aggregate can trespass mucosal barriers, circumvent innate and adoptive immunity, and travel across the blood-brain barrier to eventually provoke brain disease. To start the chapters of this book we will introduce a few topics in current prion studies read more ...