Investigation of Bovine Spongiform Encephalopathy (BSE), Sporadic Creutzfeldt-Jakob Disease (sCJD), New Variant Creutzfeldt-Jakob Disease (nvCJD), and the Controversy of the Etiological Agents Responsible for these Transmissible Spongiform Encephalopathies (TSEs)
The connection between bovine spongiform encephalopathy (BSE), known conventionally as mad cow disease, and new variant Creutzfeldt-Jakob disease (nvCJD) has brought BSE to the public eye. The disease in cattle seems to have crossed the species barrier and develop into a fatal disease in humans, both belonging to the group of diseases known as transmissible spongiform encephalopathies (TSEs). Now a single cow infected with BSE raises public anxiety because of the belief that humans who ate infected meat will sicken and die because of nvCJD. But how concrete is this connection between BSE and nvCJD? Though experimental data supports the connection, many questions have still not been answered. Recently, new studies have been done to find an alternative etiological agent to these diseases grouped as TSEs, and three UK scientists have linked BSE, sporadic Creutzfeldt-Jakob disease (sCJD), and possibly nvCJD with multiple sclerosis (MS) in a surprising new claim that all three diseases are actually autoimmune diseases.
Transmissible spongiform encephalopathies (TSEs) came into contact with the human world as early as 1732 through an Englishman's description of scrapie, a TSE that occurs in sheep and goats; there may have been even earlier cases in the 1690's if the
disease dubbed “la Tremblante” in France referred to scrapie. (Ebringer et al., 2005) TSEs are “distinct from any other amyloid-based diseases in that they alone are transmissible.” (Brown, 2004, p. 335) This distinction has caused the controversies that revolve around them, because exactly how they are transmitted remains unknown. The primary theory is that all TSEs are prion caused diseases, but unanswered questions about the precise methods that prions use have encouraged scientists to form a new theory: BSE, sCJD, and possibly nvCJD are all autoimmune disease caused by the Acinetobacter bacteria. The controversial argument along with the basic symptoms of BSE, sCJD, and nvCJD are further discussed.
Investigation of BSE, sCJD, and nvCJD 2
The total number of cases of BSE has exceeded 180,000. (Beghi et al., 2004) The disease introduction in the spring of 1985 has been linked to the UK's alteration of the meat and bonemeal (MBM) fed to cattle. Sheep and cattle parts were added to increase the protein intake, but these parts included spinal cords, brains, retinas, and distal ileums. The etiological agent of scrapie can infect all of these tissues, and can therefore be transmitted to cattle through the MBM. This is the information based on the assumption that prions are causing TSEs. Prions, called short proteins because they only have 15-20
amino acids in their chain of amino acids, are normal proteins produced in the...