Bovine Spongiform Encephalopathy: A Neuropathological Perspective

Abstract

The occurrence of bovine spongiform encephalopathy (BSE), recognition that it is a new scrapie-like disease epidemic in domestic cattle in the United Kingdom and concern of a remote zoonotic potential has, in four years, produced a plethora of documented information. While much of this information has been communicated outwith the scientific literature, this review attempts to summarise, from a neuropathological viewpoint, the main findings to emerge. The initial studies established the nosological homology of BSE with the subacute spongiform encephalopathies or "prion" diseases of animals and man. Epidemiological data are consistent with an extended common source epidemic originating from an abrupt change, commencing in 1981-82, in the exposure of domestic cattle to a scrapie-like agent in meat and bone meal incorporated into commercial animal feedstuffs. It is currently proposed that the method of production of meat and bone meal has contributed vital factors to the change in exposure. Invariability of the distribution pattern of vacuolar pathology in the natural disease and on primary transmission to cattle suggests a uniformity of the pathogenesis of BSE. Studies in mice suggest uniformity also of the biological properties of different BSE isolates but indicate that the properties differ from those of sheep scrapie isolates. Human health risks, although perceived to be negligible, have been addressed by various strategies including statutory measures and long term monitoring.

Identification of a second bovine amyloidotic spongiform encephalopathy: Molecular similarities with sporadic Creutzfeldt-Jakob disease

“…Although observed in only two cattle, the BASE phenotype could be more common than expected. In previous studies, amyloid congophilic plaques were found in 1 of 20 BSE cases examined systematically for amyloid (23), and it was reported that focal cerebral amyloidosis is present in a small proportion of BSE cases (24). Although no biochemical analysis of PrP Sc glycotype is available for these animals with ''atypical BSE phenotype,'' our present results underscore the importance of performing a strain-typing in bovine TSE with amyloid deposition.…”

In utero transmission and tissue distribution of chronic wasting disease-associated prions in free-ranging Rocky Mountain elk

“…Transmissible spongiform encephalopathies (TSEs) are a class of surreptitious neurodegenerative diseases which have been recognized for almost a century, but only became prominent in the research spotlight during the bovine spongiform encephalopathy and subsequent variant Creutzfeldt-Jakob disease outbreaks in the 1980s and 1990s (Wells et al, 1991;Hill et al, 1997;Brown et al, 2001). Many interesting and confounding aspects of TSEs have been revealed, such as the fact that the causative agent is a prion (Prusiner, 1982), a misfolded, protease-resistant form (PrP res ) of a protein with nearly universal expression in the animal kingdom (PrP C ), and whose function is still elusive and controversial, despite the enormous body of research undertaken to reveal it (Aguzzi et al, 2008;Sakudo & Onodera, 2014).…”

Animal spongiform encephalopathies ‐ an update

“…This was found in only about 5% of BSE cases, which is low when compared to the more than 50% of scrapie cases (72). The plaques immunostain with anti-PrP (prion protein) antibodies (76).…”

“…BSE has caused a resurge in interest in spongiform encephalopathies (SEs), mainly as a result of public fear of possible implications for human health. The resulting torrent of research information has been reviewed at regular intervals (482,65,76), but it is thought that recent interesting developments in this rapidly changing scene warrant this new update. BSE is a new disease of cattle, first recognized and defined in November 1986 by histopathological examination of affected brains (74).…”