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From: TSS ()
In Reply to: U.S. Investigates Possible Mad Cow Case posted by TSS on March 11, 2006 at 2:41 pm:
3/11/2006 6:07:00 PM Commonly Asked Questions About BSE in Products Regulated by FDA's Center for Food Safety and Applied Nutrition (CFSAN) In light of the December 23, 2003 diagnosis of BSE in a single cow that had been imported into the United States, CFSAN has reviewed the products it regulates to ensure their safety. What is "Mad Cow Disease" (Bovine Spongiform Encephalopathy/BSE)? Mad Cow Disease is the commonly used name for Bovine Spongiform Encephalopathy (BSE), a slowly progressive, degenerative, fatal disease affecting the central nervous system of adult cattle. Since 1990, the U.S. Department of Agriculture (USDA) has conducted aggressive surveillance of the highest risk cattle going to slaughter in the United States. To date, the only cow that has been found to be affected with BSE was the one diagnosed with BSE in December 2003. What causes BSE? The exact cause of BSE is not known but it is generally accepted by the scientific community that the likely cause is infectious forms of a type of protein, prions, normally found in animals cause BSE. In cattle with BSE, these abnormal prions initially occur in the small intestines and tonsils, and are found in central nervous tissues, such as the brain and spinal cord, and other tissues of infected animals experiencing later stages of the disease. Was a case of BSE identified in the U.S. in December 2003? Yes, the USDA surveillance program identified the first BSE case in the U.S. in a dairy cow in Washington State. The cow was bought from a farm in Canada. Did meat and meat products from the BSE cow enter the food supply? As soon as the BSE case was identified, both USDA and FDA activated their BSE Emergency Response Plans, and USDA immediately recalled the meat. Meat that did enter the food supply was quickly traced and was removed from the marketplace. Moreover, all the organs in which infectious prions occur were removed at slaughter and did not enter the food supply. Consumers should feel very confident that the system of multiple firewalls maintained by Federal agencies protects them from possible exposure to BSE. In addition, we believe it is important for consumers to also understand that scientific research indicates that muscle meat is not a source of infectious prions. Will there be additional cases? In 1998, USDA commissioned the Harvard Center for Risk Analysis to conduct an analysis and evaluation of the U.S. regulatory measures to prevent the spread of BSE in the U.S. and to reduce the potential exposure of U.S. consumers to BSE. The Harvard study concluded that, if introduced, due to the preventive measures currently in place in the U.S., BSE is extremely unlikely to become established in the United States. FDA and other Federal agencies have been vigilant in strengthening protective measures to reduce the U.S. consumer's risk of exposure to BSE-contaminated food and cosmetic products. Since 1989, USDA has banned imports of live ruminants, such as cattle, sheep and goats, and most products from these animals from countries known to have BSE. Subsequently, USDA expanded this ban to include both countries with BSE and countries at risk for BSE. In 1997, FDA prohibited, with some exceptions, the use of protein derived from mammalian tissues in animal feed intended for cows and other ruminants. See the FDA/CVM website at www.fda.gov/cvm for further information on the "ruminant feed ban." On Jan. 8, 2004, the USDA's Food Safety and Inspection Service issued new rules to enhance safeguards against BSE. Details on these rules may be found at USDA's website, www.usda.gov. Also in 2004, FDA issued a rule that prohibits the use of certain cattle material, because of the risk of BSE, in human food and cosmetics. Does BSE affect people? There is a disease similar to BSE called Creutzfeldt-Jacob Disease (CJD) that is found in people. A variant form of CJD (vCJD) is believed to be caused by eating contaminated beef products from BSE-affected cattle. To date, there have been 155 confirmed and probable cases of vCJD worldwide among the hundreds of thousands of people that may have consumed BSE-contaminated beef products. The one reported case of vCJD in the United States was in a young woman who contracted the disease while residing in the UK and developed symptoms after moving to the U.S. What additional measures are being taken to ensure food safety in the U.S. from BSE? Since 1989, the FDA and other federal agencies have had ongoing regulatory measures in place to prevent BSE contamination of U.S. food and food products. Following the identification in a Washington state dairy herd of a BSE-positive cow imported from Canada, USDA issued new regulations containing additional safeguards to further minimize risk for introduction of the BSE agent into the U.S. food supply. See USDA's website www.usda.gov for further information.. Similarly, FDA has prohibited the use of the cattle materials that carry the highest risk of BSE in human food, including dietary supplements, and in cosmetics. FDA's rule prohibits use of the following cattle material in human food and cosmetics: cattle material from non-ambulatory, disabled cattle, FDA's rule also requires that food and cosmetics manufacturers and processors make available to FDA any existing records relevant to their compliance with these prohibitions. FDA has also published a proposal requiring manufacturers and processors of food and cosmetics made with cattle material to establish and maintain records demonstrating that their products do not contain prohibited cattle material. Is the food in the U.S. likely to be a BSE risk to consumers? FDA and other federal agencies have had preventive measures in place to reduce the U.S. consumer's risk of exposure to any BSE-contaminated meat and food products. Since 1989, USDA has prohibited the importation of live animals and an imal products from BSE-positive countries. Subsequently, USDA expanded the ban to include both countries with BSE and countries at risk for BSE. Since 1997, FDA has prohibited the use of most mammalian protein in the manufacture of ruminant feed. In 2004, FDA issued a rule prohibiting the use of certain cattle materials in human food and cosmetics, and USDA issued a rule prohibiting certain cattle materials from use as human food. Is cow's milk a source of BSE? Scientific research indicates that BSE is not transmitted in cow's milk, even if the milk comes from a cow with BSE. Milk and milk products, even in countries with a high incidence of BSE are, therefore, considered safe. Can milk be infected with BSE from a BSE-positive cow? No detectable infectivity in cow's milk has been reported from any BSE-infected cows. Infectious prions have not been detected by bioassay of milk from cattle with BSE. Does the use of bovine-derived ingredients in dietary supplements mean that they are not safe? No. The requirements that FDA has in place should give consumers confidence that their food, including dietary supplements, is safe. Most recently, FDA published a rule that prohibits the use in human food, including dietary supplements, of the cattle materials that have the highest risk of harboring BSE infectivity. The rule applies to both imported and domestic dietary supplements and their ingredients. Furthermore, most ingredients used to produce dietary supplements and most other food ingredients come from cattle that are slaughtered when they are less than 30-months of age and, because of their age, present little risk of being BSE-positive. It is not a common occurrence for animals younger than 30 months to develop BSE. Since the BSE-positive cow was discovered in the U.S., does that mean that dietary supplements made with domestic ingredients might be unsafe? No. The requirements that FDA has in place should give consumers confidence that their food, including dietary supplements, is safe. Most recently, FDA published a rule that prohibits the use in human food, including dietary supplements, of the cattle materials that have the highest risk of harboring BSE infectivity. Furthermore, most ingredients used to produce dietary supplements and most other food ingredients come from cattle that are slaughtered when they are less than 30-months of age and, because of their age, present little risk of being BSE-positive. Even though an imported BSE-positive cow was identified in the U.S., the risk to human health from dietary supplements and other foods containing cattle-derived ingredients is extremely low. What steps is FDA currently taking to ensure the safety of dietary supplements that contain bovine ingredients? Most recently, FDA published a rule that prohibits the use in human food, including dietary supplements, of the cattle materials that have the highest risk of harboring BSE infectivity. The rule applies to both domestic and imported dietary supplements and their ingredients. In addition, most ingredients used to produce dietary supplements and most other food ingredients come from cattle that are slaughtered when they are less than 30-months of age and, because of their age, present little risk of being BSE-positive. Further, the restrictions by USDA on the use of certain cattle and cattle tissues in human food also reduce the risks that potentially infective tissue would be used in dietary supplements. FDA also has proposed a requirement that manufacturers and processors that use cattle material in their products would be required to keep records demonstrating that these materials do not contain prohibited cattle material and that these records be made available to FDA for inspection. Given the recent BSE case in Washington State, should consumers be concerned about cosmetics made using tallow from the rendering process? No. The World Health Organization considers tallow to be a low risk for transmission of BSE. Specifically, the rendering process separates fats from proteins. Because the disease is transmitted by prions, which are a type of protein, they would be separated by the rendering process from the tallow or fat, which is the portion that goes into cosmetics. Additionally, the tallow is processed with excessive heat and pressure which may further minimize any risk of infectivity prior to use in cosmetics. What about the use of gelatin, another bovine-related material, in cosmetics and dietary supplements and other foods? FDA's rule prohibiting the use of the cattle materials that have the highest risk of harboring BSE infectivity in human food applies to gelatin. Therefore, gelatin used in human food may not be made from these cattle materials. When and how did BSE in cattle occur? BSE in cattle was first reported in 1986 in the United Kingdom (UK). The exact origins of BSE remain uncertain, but it is thought that cattle initially may have become infected when fed feed contaminated with scrapie-infected sheep meat-and-bone meal (MBM). Scrapie is a prion disease in sheep similar to BSE in cattle. The scientific evidence suggests that the U.K. BSE outbreak in cattle then was expanded by feeding BSE-contaminated cattle protein (MBM) to calves. The definitive nature of the BSE agent is not completely known. The agent is thought to be a modified form of a protein, called a prion, which becomes infectious and accumulates in neural tissues causing a fatal, degenerative, neurological disease. These abnormal prions are resistant to common food disinfection treatments, such as heat, to reduce or eliminate their infectivity or presence. Research is ongoing to better understand TSE diseases and the nature of prion transmission. Is BSE in cattle the same disease as CWD in deer and elk in the U.S.? BSE is a Transmissible Spongiform Encephalopathy (TSE), a family of similar diseases that may infect certain species of animals and people such as scrapie in sheep and goats, BSE in cattle, chronic wasting disease (CWD) in deer and elk, and variant Creutzfeldt-Jakob disease (vCJD) in people. To date, there is no scientific evidence that BSE in cattle is related to CWD in deer and elk. FDA is working closely with other government agencies and the public health community to address CWD in wild and domesticated deer and elk herds. Wildlife and public health officials advise people not to harvest, handle, or consume any wild deer or elk that appear to be sick, regardless of the cause, especially in those states where CWD has been detected. What countries have reported cases of BSE or are considered to have a substantial risk associated with BSE? These countries are: Albania, Austria, Belgium, Bosnia-Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Federal Republic of Yugoslavia, Finland, France, Germany, Greece, Hungary, Ireland, Israel, Italy, Liechtenstein, Luxembourg, former Yugoslavia Republic of Macedonia, The Netherlands, Norway, Oman, Poland, Portugal, Romania, Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Japan, and United Kingdom (Great Britain including Northern Ireland and the Falkland Islands). Canada (May 2003) and the U.S. (December 2003) each have recently reported one BSE-positive cow but remain countries considered to have a low risk. The U.S. BSE-positive cow reported in December 2003 was confirmed to have been imported from Canada in 2001. http://www.cattlenetwork.com/content.asp?contentid=22602 3/11/2006 6:11:00 PM Late Friday, officials with USDA’s Animal and Plant Health Inspection Service received inconclusive rapid test results from an animal sampled as part of the ongoing enhanced BSE surveillance program. The animal did not enter the food or feed supply. USDA is conducting confirmatory tests at the National Veterinary Services Laboratory in Ames, Iowa, using both the immunohistochemistry analysis and Western blot testing methods. USDA expects the additional tests to be completed in four to seven days. "This inconclusive result does not mean we have found a new case of BSE. Inconclusive results are a normal component of most screening tests, which are designed to be extremely sensitive so they will detect any sample that could possibly be positive,” said Chief Veterinary Medical Officer John Clifford, in a statement Saturday. The BSE agent is not found in whole muscle cuts of beef, such as steaks and roasts, or ground beef. Any tissues considered at risk for carrying the BSE agent are removed at the processing plant and excluded from the food or feed supply. Even if inconclusive tests are confirmed as BSE, scientists, government experts and food industry leaders agree U.S. beef will remain very safe due to the firewalls in place to protect consumers and the nation’s cattle herd. NCBA and KLA will continue to monitor the situation throughout the weekend. http://www.cattlenetwork.com/content.asp?contentid=22603 > In 1998, USDA commissioned the Harvard Center for Risk Analysis to conduct an analysis and evaluation of the U.S. regulatory measures to > prevent the spread of BSE in the U.S. and to reduce the potential exposure of U.S. consumers to BSE. The Harvard study concluded that, if > introduced, due to the preventive measures currently in place in the U.S., BSE is extremely unlikely to become established in the United States. THIS is the first rubber-stamp that is whooped out. but it's just more BSe. SEE for yourself, and then ask yourself why they don't quote this ; SUPPRESSED peer review of Harvard study October 31, 2002 http://www.fsis.usda.gov/oa/topics/BSE_Peer_Review.pdf > Late Friday, officials with USDA’s Animal and Plant Health Inspection Service received > inconclusive rapid test results from an animal sampled as part of the ongoing enhanced BSE > surveillance program. The animal did not enter the food or feed supply. THIS quote is another rubber stamp they have ;-) this is for marketing purposes i.e. give the market time to digest. FUNNY or another coincidence how most of these inconclusives come out on Friday ;-) 2. Packers and Stockyards Programs: Continuing Problems with GIPSA Investigations of Competitive Practices, by Daniel Bertoni, acting director, natural resources and environment, before the Senate Committee on Agriculture, Nutrition, and Forestry. GAO-06-532T, March 9. OIG has been very busy thank God. they send the sample to Weybridge like the original BSE response plan called for, before GW et al traded there soul and ours for the BSE MRR policy, GWs answer to mad cow disease i.e. the legal trading of all strains of TSE aka mad cow diseases. the original BSE response plan also called for the tissue sample to be hand carried to Weybridge and a 24 to 96 hour turnaround on confirmation if i am not mistaken. nope, if this baby comes back negative and they don't send the sample to Weybridge for additional confirmation, then the Honorable Phyllis Fong and the OIG will have to get there paddle out again. past history shows they used the lease likely to detect BSE/TSE, even after one of ther top prion gods told them so in 2003. maybe that is why she was put out to pasture with a few others. but old ronald mcdonald and the big mac knew what they were doing; NOW, let us look at another BSE ROUNDTABLE DISCUSSION by USDA et al in the year 2003, please note the BSE science on IHC testing then, and then compare to now, and then ponder those other 9,200 cattle of the infamous June 2004 BSE cover-up program, that did not have rapid testing or WB, just IHC, the lease likely to find BSE/TSE ; We have to be careful that we don't get so set in the way we do things that Dr. Detwiler: That's on the slaughter. But on the clinical cases, aren't Dr. Keller: Tissues are routinely tested, based on which tissue provides an Dr. Detwiler: That's on the slaughter. But on the clinical cases, aren't The BSE enhanced surveillance program involves the use of a rapid screening test, followed by confirmatory testing for any samples that come back "inconclusive." The weekly summary below captures all rapid tests conducted as part of the enhanced surveillance effort. It should be noted that since the enhanced surveillance program began, USDA has also conducted approximately 9,200 routine IHC tests on samples that did not first undergo rapid testing. http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-EC244-Attach-1.pdf SEROLOGICALS CORPORATION http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-c000383-01-vol35.pdf Dick Crawford Corporate Vice President, Government Relations 630-623-6754 Direct 630-623-3057 Facsimile dick.crawford@mcd.com http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273_emc-000134-02.pdf 03-025IFA Docket No. 2002N-0273 C-534 VOL 45 (PhRMA) and Entered On February 17, 2006 Marie A. Vodicka, PhD Assistant Vice President Biologics & Blotechnology Scientlflc & Regulatory Affairs SCIENCE & REG AFFAIRS Division of Dockets Management (HFA-305) Linda Detwiler, DVM Consultant, TSE Risk Management Robert G. Rohwer, Ph.D. Director, Molecular Neurovirology Laboratory Veterans Affairs Medical Center Medical Research Service 151 http://0-www.fda.gov.lilac.une.edu/OHRMS/DOCKETS/dockets/04n0081/04N-0081_emc-000005-01.pdf Animal Food or Feed; Animal Proteins Prohibited in Ruminant Feed Comment Number: EC -10 Accepted - Volume 2 PART 2 Docket No, 04-047-l Regulatory Identification No. (RIN) 091O-AF46 NEW BSE SAFEGUARDS (comment submission) https://web01.aphis.usda.gov/regpublic.nsf/0/eff9eff1f7c5cf2b87256ecf000df08d?OpenDocument https://web01.aphis.usda.gov/BSEcom.nsf/0/b78ba677e2b0c12185256dd300649f9d?OpenDocument&AutoFramed Docket No. 2003N-0312 Animal Feed Safety System [TSS SUBMISSION] genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest _sporadic_ CJD; http://www.fda.gov/ohrms/dockets/ac/03/slides/3923s1_OPH.htm Sr. [flounder@wt.net] Monday, January 08,200l 3:03 PM freas ... Report The European Food Safety Authority and its Scientific Expert Working Group on the Assessment of the Geographical Bovine Spongiform Encephalopathy (BSE) Risk (GBR) were asked by the European Commission (EC) to provide an up-to-date scientific report on the GBR in the United States of America, i.e. the likelihood of the presence of one or more cattle being infected with BSE, pre-clinically as well as clinically, in USA. This scientific report addresses the GBR of USA as assessed in 2004 based on data covering the period 1980-2003. The BSE agent was probably imported into USA and could have reached domestic cattle in the middle of the eighties. These cattle imported in the mid eighties could have been rendered in the late eighties and therefore led to an internal challenge in the early nineties. It is possible that imported meat and bone meal (MBM) into the USA reached domestic cattle and leads to an internal challenge in the early nineties. A processing risk developed in the late 80s/early 90s when cattle imports from BSE risk countries were slaughtered or died and were processed (partly) into feed, together with some imports of MBM. This risk continued to exist, and grew significantly in the mid 90’s when domestic cattle, infected by imported MBM, reached processing. Given the low stability of the system, the risk increased over the years with continued imports of cattle and MBM from BSE risk countries. EFSA concludes that the current GBR level of USA is III, i.e. it is likely but not confirmed that domestic cattle are (clinically or pre-clinically) infected with the BSE-agent. As long as there are no significant changes in rendering or feeding, the stability remains extremely/very unstable. Thus, the probability of cattle to be (pre-clinically or clinically) infected with the BSE-agent persistently increases. Publication date: 20 August 2004 http://www.efsa.eu.int/science/tse_assessments/gbr_assessments/573_it.html i just cannot accept this; > 23 kg of meat in a suitcase (suitcase bomb...TSS) > The data do not provide a species of origin code for these > products, therefore they may not contain any ruminant product. what kind of statement is this? how stupid do they think we are? it could also very well mean that _all_ of it was ruminant based products ! > Poland included non-species specific animal products > used in animal feeds and non-species specific sausage and offal > products (Table 3). Given US restrictions on ruminant product > imports, these US imports should not have contained ruminant > material. http://europa.eu.int/comm/food/fs/sc/ssc/out185_en.pdf 2006 POLAND BSE 01/2006 Poland Bse and animal nutrition 7693-2005 Annexes Subject: New case of mad cow disease in Poland AFX News Limited SNIP...END Definite and probable CJD cases in the UK: As at 3 March 2006 Summary of vCJD cases Deaths Deaths from definite vCJD (confirmed): 110 Deaths from probable vCJD (without neuropathological confirmation): 44 Deaths from probable vCJD (neuropathological confirmation pending): 0 Number of deaths from definite or probable vCJD (as above): 154 Alive Number of probable vCJD cases still alive: 6 Total number of definite or probable vCJD (dead and alive): 160 The next table will be published on Monday 3rd April 2006 Referrals: a simple count of all the cases which have been referred to the National CJD Surveillance Unit for further investigation in the year in question. CJD may be no more than suspected; about half the cases referred in the past have turned out not to be CJD. Cases are notified to the Unit from a variety of sources including neurologists, neuropathologists, neurophysiologists, general physicians, psychiatrists, electroencephalogram (EEG) departments etc. As a safety net, death certificates coded under the specific rubrics 046.1 and 331.9 in the 9th ICD Revisions are obtained from the Office for National Statistics in England and Wales, the General Register Office for Scotland and the General Register Office for Northern Ireland. Deaths: All columns show the number of deaths that have occurred in definite and probable cases of all types of CJD and GSS in the year shown. The figures include both cases referred to the Unit for investigation while the patient was still alive and those where CJD was only discovered post mortem (including a few cases picked up by the Unit from death certificates). There is therefore no read across from these columns to the referrals column. The figures will be subject to retrospective adjustment as diagnoses are confirmed. Definite cases: this refers to the diagnostic status of cases. In definite cases the diagnosis will have been pathologically confirmed, in most cases by post mortem examination of brain tissue (rarely it may be possible to establish a definite diagnosis by brain biopsy while the patient is still alive). Probable vCJD cases: are those who fulfil the ‘probable’ criteria set out in the Annex and are either still alive, or have died and await post mortem pathological confirmation. Those still alive will always be shown within the current year's figures. Sporadic: Classic CJD cases with typical EEG and brain pathology. Sporadic cases appear to occur spontaneously with no identifiable cause and account for 85% of all cases. Probable sporadic: Cases with a history of rapidly progressive dementia, typical EEG and at least two of the following clinical features; myoclonus, visual or cerebellar signs, pyramidal/extrapyramidalsigns or akinetic mutism. Iatrogenic: where infection with classic CJD has occurred accidentally as the result of a medical procedure. All UK cases have resulted from treatment with human derived pituitary growth hormones or from grafts using dura mater (a membrane lining the skull). Familial: cases occurring in families associated with mutations in the PrP gene (10 - 15% of cases). GSS: Gerstmann-Straussler-Scheinker syndrome - an exceedingly rare inherited autosomal dominant disease, typified by chronic progressive ataxia and terminal dementia. The clinical duration is from 2 to 10 years, much longer than for CJD. vCJD: Variant CJD, the hitherto unrecognised variant of CJD discovered by the National CJD Surveillance Unit and reported in The Lancet on 6 April 1996. This is characterised clinically by a progressive neuropsychiatric disorder leading to ataxia, dementia and myoclonus (or chorea) without the typical EEG appearance of CJD. Neuropathology shows marked spongiform change and extensive florid plaques throughout the brain. Definite vCJD cases still alive: These will be cases where the diagnosis has been pathologically confirmed (by brain biopsy). Related links DIAGNOSTIC CRITERIA FOR VARIANT CJD I A) PROGRESSIVE NEUROPSYCHIATRIC DISORDER B) DURATION OF ILLNESS > 6 MONTHS C) ROUTINE INVESTIGATIONS DO NOT SUGGEST AN ALTERNATIVE DIAGNOSIS D) NO HISTORY OF POTENTIAL IATROGENIC EXPOSURE II A) EARLY PSYCHIATRIC SYMPTOMS * B) PERSISTENT PAINFUL SENSORY SYMPTOMS ** C) ATAXIA D) MYOCLONUS OR CHOREA OR DYSTONIA E) DEMENTIA III A) EEG DOES NOT SHOW THE TYPICAL APPEARANCE OF SPORADIC CJD *** (OR NO EEG PERFORMED) B) BILATERAL PULVINAR HIGH SIGNAL ON MRI SCAN IV A) POSITIVE TONSIL BIOPSY DEFINITE: IA (PROGRESSIVE NEUROPSYCHIATRIC DISORDER) and NEUROPATHOLOGICAL CONFIRMATION OF vCJD **** PROBABLE: I and 4/5 OF II and III A and III B or I and IV A * depression, anxiety, apathy, withdrawal, delusions. ** this includes both frank pain and/ or unpleasant dysaesthesia *** generalised triphasic periodic complexes at approximately one per second ****spongiform change and extensive PrP deposition with florid plaques, throughout the cerebrum and cerebellum. http://www.dh.gov.uk/assetRoot/04/13/11/73/04131173.pdf if you look at 2003 there were 3 type unknown. wonder if they were the same or different than the unknown in 2005? considering the soup that has been brewing over here in the USA for years via the rendering of BSE and atypical TSE in cattle, CWD, Scrapie, a few TME cases (not too much due to scent gland, but there were a few rendered, but all this, and you have one hell of a recipe for a new strains of TSE in humans. then who knows what 'friendly fire' cases would look like from this soup via secondary transmission via medical/surgical/dental arena. ...TSS http://www.cjdsurveillance.com/resources-casereport.html HUMAN and ANIMAL TSE Classifications i.e. mad cow TSEs have been rampant in the USA for decades in many SOURCES Creutzfeldt-Jakob disease ratio of protease-resistant prion protein (PrPSc), and type 2 PrPSc display unglycosylated core fragments of acids 82 and 97, respectively. Methods We generated anti-PrP monoclonal antibodies to K cleavage sites. These antibodies, which were Findings We studied 114 brain samples from 70 patients Every patient classified as CJD type 2, and all variant cerebellum and other PrPSc-rich brain areas, with a Interpretation The regular coexistence of multiple electrophoretic PrPSc mobilities as surrogates for classifications. into debate and introduce interesting questions about human CJD types. For example, do human prion types exist in a dynamic equilibrium in the brains of affected individuals? Do they coexist in most or even all CJD cases? Is the biochemically identified PrPSc type simply the dominant type, and not the only PrPSc species? Detection of Type 1 Prion Protein in Variant Creutzfeldt-Jakob Disease Helen M. Yull,* Diane L. Ritchie,* Jan P.M. Langeveld,? Fred G. van Zijderveld,? Moira E. Bruce,? James W. Ironside,* and Mark W. Head* From the National CJD Surveillance Unit,* School of and Clinical Medicine, University of Edinburgh, Edinburgh, United Kingdom; Central Institute for Animal Disease (CIDC)-Lelystad, ? Lelystad, The Netherlands; Institute Health, Neuropathogenesis Unit, ? Edinburgh, United Kingdom Molecular typing of the abnormal form of the prion protein (PrPSc) has come to be regarded as a powerful tool in the investigation of the prion diseases. All thus far presented indicates a single PrPSc molecular type in variant Creutzfeldt-Jakob disease (termed type 2B), presumably resulting from infection with a single strain of the agent (bovine spongiform Here we show for the first time that the PrPSc that accumulates in the brain in variant Creutzfeldt- Jakob disease also contains a minority type 1 component. This minority type 1 PrPSc was found in all 21 cases of variant Creutzfeldt-Jakob disease tested, of brain region examined, and was also present in the variant Creutzfeldt-Jakob disease tonsil. The quantitative balance between PrPSc types was maintained when variant Creutzfeldt-Jakob disease was transmitted to wild-type mice and was also found in bovine spongiform encephalopathy cattle brain, indicating that the agent rather than the host specifies their relative representation. These results indicate that PrPSc molecular typing is based on quantitative rather than qualitative phenomena and point to a complex relationship between prion protein biochemistry, disease phenotype and agent strain. (Am J Pathol 2006, 168:151-157; DOI: 10.2353/ajpath.2006.050766) In the apparent absence of a foreign nucleic acid genome associated with the agents responsible for transmissible spongiform encephalopathies or prion diseases, efforts to provide a molecular definition of agent strain have focused on biochemical differences in the abnormal, disease-associated form of the prion protein, termed PrPSc. Differences in PrPSc conformation and glycosylation have been proposed to underlie disease phenotype and form the biochemical basis of agent strain. This proposal has found support in the observation that the major phenotypic subtypes of sCJD appear to correlate with the presence of either type 1 or type 2 PrPSc in combination with the presence of either methionine or valine at codon 129 of the prion protein gene.2 Similarly, the PrPSc type associated with vCJD correlates with the presence of type 2 PrPSc and is distinct from that found in sCJD because of a characteristically high occupancy of both N-linked glycosylation sites (type 2B).6,11 The means by which such conformational difference is detected is somewhat indirect; relying on the action of proteases, primarily proteinase K, to degrade the normal Figure 6. Type 1 PrPSc is a stable minority component brain. Western blot analysis of PrP in a sample of of vCJD during digestion with proteinase K is shown. are indicated in minutes (T0, 5, 10, 30, 60, 120, 180). probed with 3F4, which detects both type 1 and type 2 which detects type 1. The insert shows a shorter course study from a separate experiment also probed included samples of cerebral cortex from a case of 1) and molecular weight markers (Markers) indicate Figure 7. A minority type 1-like PrPSc is found in vCJD to mice and in BSE. Western blot analysis of PrPSc in a sample of tonsil from a case of vCJD (Tonsil), in a of a wild-type mouse (C57BL) infected with vCJD and in BSE brain (BSE) is shown. Tissue extracts were digested Duplicate blots were probed with either 3F4 or 6H4, type 1 and type 2 PrPSc, and with 12B2, which detects included samples of cerebral cortex from a case of 1) and molecular weight markers (Markers) indicate Type 1 PrPSc in Variant Creutzfeldt-Jakob Disease 155 AJP January 2006, Vol. 168, No. 1 cellular form of PrP and produce a protease-resistant core fragment of PrPSc that differs in the extent of its N-terminal truncation according to the original conformation. A complication has recently arisen with the finding that both type 1 and type 2 can co-exist in the brains of patients with sCJD.2,5-8 More recently this same phenomenon has been demonstrated in patients with iatrogenically acquired and familial forms of human prion disease. 9,10 The existence of this phenomenon is now beyond doubt but its prevalence and its biological remain a matter of debate. Conventional Western blot analysis using antibodies that detect type 1 and type 2 PrPSc has severe quantitative limitations for the co-detection of type 1 and type 2 PrPSc in individual samples, suggesting that the prevalence of co-occurrence of the two types might be underestimated. We have sought to circumvent this problem by using an antibody that is type 1-specific and applied this to the sole remaining human prion disease where the phenomenon of mixed PrPSc types has not yet been shown, namely vCJD. These results show that even in vCJD where susceptible individuals have been infected supposedly by a single strain of agent, both PrPSc types co-exist: a reminiscent of that seen when similarly discriminant antibodies were used to analyze experimental BSE in sheep.14,17 In sporadic and familial CJD, individual brains can show a wide range of relative amounts of the two types in samples from different regions, but where brains have been thoroughly investigated a predominant type is usually evident.2,6,10 This differs from this on vCJD, where type 1 is present in all samples but always as a minor component that never reaches a level at which it is detectable without a type 1-specific antibody. It would appear that the relative between type 1 and type 2 is controlled within certain limits in the vCJD brain. A minority type-1-like band is also detected by 12B2 in vCJD tonsil, in BSE brain and in the brains of mice experimentally infected with vCJD, suggesting that this balance of types is agent, rather than host or tissue, specific. Interestingly the signature" of the type 2 PrPSc found in vCJD (type 2B) is also seen in the type 1 PrPSc components, suggesting that it could legitimately be termed type 1B. PrPSc isotype analysis has proven to be extremely useful in the differential diagnosis of CJD and is continue to have a major role in the investigation of human prion diseases. However, it is clear, on the basis of these findings, that molecular typing has quantitative and that any mechanistic explanation of prion replication and the molecular basis of agent strain must accommodate the co-existence of multiple prion protein conformers. Whether or not the different conformers we describe here correlate in a simple and direct way with agent strain remains to be determined. In principle two interpretations present themselves: either the two conformers can be produced by a single strain of agent or vCJD (and, therefore, presumably BSE) results from a mixture of strains, one of which generally Evidence for the isolation in mice of more than one strain from individual isolates of BSE has been presented previously.18,19 One practical consequence of our findings is that the correct interpretation of transmission studies will depend on a full examination of the balance of molecular types present in the inoculum used to transmit disease, in to a thorough analysis of the molecular types that arise in the recipients. Another consequence relates to the diagnostic certainty of relying on PrPSc molecular type alone when considering the possibility of BSE or secondary transmission in humans who have a genotype other than methionine at codon 129 of the PRNP gene. In this context it is interesting to note minority type 1B component resembles the type 5 PrPSc described previously to characterize vCJD transmission into certain humanized PRNP129VV transgenic mouse models.12,20 This apparently abrupt change in molecular phenotype might represent a selection process imposed by this particular transgenic mouse model. Irrespective of whether this proves to be the case, the results shown here point to further complexities in the relationship the physico-chemical properties of the prion protein, human disease phenotype, and prion agent strain. Acknowledgments AJP January 2006, Vol. 168, No. 1 ...TSS http://ajp.amjpathol.org/cgi/content/abstract/168/1/151maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=prion&searchid=1136646133963_237&FIRSTINDEX=0&volume=168&issue=1&journalcode=amjpathol (2005), 31 , 565-579 doi: 10.1111/j.1365-2990.2005.00697.x © 2005 Blackwell Publishing Ltd 565 Blackwell Science, LtdOxford, UKNANNeuropathology and 316565579 Review article Phenotypic variability in human prion diseases J. W. Ironside, D. L. Ritchie and M. W. Head National Creutzfeldt-Jakob Disease Surveillance Unit, J. W. Ironside, D. L. Ritchie and M. W. Head (2005) Neuropathology and Applied Neurobiology 31, 565-579 Phenotypic variability in human prion diseases Human prion diseases are rare neurodegenerative disorders that can occur as sporadic, familial or acquired disorders. Within each of these categories there is a wide range of phenotypic variation that is not encountered in other neurodegenerative disorders. The identification of the prion protein and its key role in the pathogenesis of this diverse group of diseases has allowed a fuller of factors that influence disease phenotype. In particular, the naturally occurring polymorphism at codon 129 in the prion protein gene has a major influence on the phenotype in sporadic, familial and acquired prion diseases, although the underlying mechanisms remain unclear. Recent technical advances have improved our ability to study the isoforms of the abnormal prion protein in the brain and in other tissues. This has lead to the of molecular strain typing, in which different isoforms of the prion protein are proposed to correspond to individual strains of the transmissible agent, each with specific biological properties. In sporadic disease there are at least six major combinations of codon 129 genotype and prion protein isotype, which appear to relate to distinctive clinical subgroups of this disease. However, these relationships are proving to be more complex than first considered, particularly in cases with more than a single prion protein isotype in the brain. Further work is required to clarify these relationships and to explain the mechanism of neuropathological targeting of specific brain regions, which accounts for the diversity of clinical features within human prion diseases. sporadic CJD-like prion strains in transgenic mice expressing human prion protein Melanie Desbruslais, Susan Joiner, Ian Gowland, Andrew L.Wood, Julie Welch, Andrew F.Hill, Sarah E.Lloyd, Jonathan D.F.Wadsworth and John Collinge1 MRC Prion Unit and Department of Neurodegenerative Disease, Institute of Neurology, University College, Queen Square, London WC1N 3BG, UK 1Corresponding author e-mail: j.collinge@prion.ucl.ac.uk recognized to date only in individuals homozygous for methionine at PRNP codon 129. Here we show that transgenic mice expressing human PrP methionine 129, inoculated with either bovine spongiform encephalopathy (BSE) or variant CJD prions, may develop the neuropathological and molecular phenotype of vCJD, consistent with these diseases being caused by the same prion strain. Surprisingly, however, BSE transmission to these transgenic mice, in addition to producing a vCJD-like phenotype, can also result in a distinct molecular phenotype that is from that of sporadic CJD with PrPSc type 2. These data suggest that more than one BSEderived prion strain might infect humans; it is therefore possible that some patients with a phenotype consistent with sporadic CJD may have a disease arising from BSE exposure. is caused by a BSE-like prion strain. Also, remarkably, the key neuropathological hallmark of vCJD, the presence of abundant ¯orid PrP plaques, can be recapitulated on BSE or vCJD transmission to these mice. However, the most surprising aspect of the studies was the ®nding that an alternate pattern of disease can be induced in 129MM Tg35 mice from primary transmission of BSE, with a molecular phenotype indistinguishable from that of a of sporadic CJD. This ®nding has important potential implications as it raises the possibility that some humans infected with BSE prions may develop a clinical disease indistinguishable from classical CJD associated with type 2 PrPSc. This is, in our experience, the commonest molecular sub-type of sporadic CJD. In this regard, it is of interest that the reported incidence of sporadic CJD has risen UK since the 1970s (Cousens et al., 1997). This has been attributed to improved case ascertainment, particularly as much of the rise is reported from elderly patients and similar rises in incidence were noted in other European countries without reported BSE (Will et al., 1998). However, it is now clear that BSE is present in many European countries, albeit at a much lower incidence than was seen in the UK. While improved ascertainment is likely to be a major factor in this rise, that some of additional cases may be related to BSE exposure cannot be ruled out. It is of interest in this regard that a 2-fold increase in the reported incidence of sporadic CJD in 2001 has recently been reported for Switzerland, a country that had the highest incidence of cattle BSE in continental Europe between 1990 and 2002 (Glatzel et al., 2002). No epidemiological case±control studies with strati®cation of CJD cases by molecular sub-type have yet been reported. It will be important to review the incidence of sporadic CJD associated with PrPSc type 2 and other molecular in both BSE-affected and unaffected countries in the result in propagation of type 2 PrPSc, it would be expected that such cases would be indistinguishable on clinical, pathological and molecular criteria from classical CJD. It may also be expected that such prions would behave biologically like those isolated from humans with sporadic CJD with type 2 PrPSc. The transmission properties of prions associated with type 2 PrPSc from BSE-inoculated 129MM Tg35 mice are being investigated by serial passage. We consider these data inconsistent with contamination of some of the 129MM Tg35 mice with sporadic CJD prions. These transmission studies were performed according to rigorous biosafety protocols for preparation of inocula and both the inoculation and care of mice, which are all uniquely identi®ed by sub-cutaneous transponders. However, crucially, the same BSE inocula have been used on 129VV Tg152 and 129MM Tg45 mice, which are highly sensitive to sporadic CJD but in which such transmissions producing type 2 PrPSc were not observed. Furthermore, in an independent experiment, separate inbred lines of wild-type mice, which are highly resistant to sporadic CJD prions, also propagated two distinctive PrPSc types on challenge with either BSE or vCJD. No evidence of spontaneous prion disease or PrPSc has been seen in groups of uninoculated or mock-inoculated aged 129MM Tg35 mice. While distinctive prion isolates have been derived from BSE passage in mice previously (designated 301C and 301V), these, in contrast to the data presented here, are propagated in mice expressing different prion proteins (Bruce et al., 1994). It is unclear whether our ®ndings indicate the existence of more than one prion strain in individual cattle with BSE, with selection and preferential replication of distinct strains by different hosts, or that `mutation' of a unitary BSE strain occurs in some types of host. Western blot analysis of single BSE isolates has not shown evidence of the presence of a proportion of monoglycosylated dominant PrPSc type in addition to the diglycosylated dominant pattern (data not shown). Extensive strain typing of large numbers of individual BSE-infected cattle either by biological or molecular methods has not been reported. Presumably, the different genetic background of the different inbred mouse lines is crucial in determining which prion strain propagates on BSE inoculation. The transgenic mice described here have a mixed genetic background with contributions from FVB/N, C57BL/6 and 129Sv inbred lines; each mouse will therefore have a different genetic background. This may explain the differing response of individual 129MM Tg35 mice, and the difference between 129MM Tg35 and 129MM Tg45 mice, which are, like all transgenic lines, populations derived from single founders. Indeed, the consistent distinctive strain propagation in FVB and C57BL/6 versus SJL and RIIIS lines may allow mapping of genes relevant to strain selection and propagation, and these studies progress. That different prion strains can be consistently isolated in different inbred mouse lines challenged with BSE prions argues that other species exposed to BSE may develop prion diseases that are not recognizable as being caused by the BSE strain by either biological or molecular strain typing methods. As with 129MM Tg35 mice, the prions replicating in such transmissions may be from naturally occurring prion strains. It remains of considerable concern whether BSE has transmitted to, and is being maintained in, European sheep ¯ocks. Given the diversity of sheep breeds affected by scrapie, it has to be considered that some sheep might have become infected with BSE, but propagated a distinctive strain type indistinguishable from those of natural sheep scrapie. ... 6358 ãEuropean Molecular Biology Organization http://embojournal.npgjournals.com/cgi/reprint/21/23/6358 This study characterizes the type and timing of Historically, psychiatric manifestations have been Personal Communication Subject: re-BSE prions propagate as either variant CJD-like or sporadic CJD Date: Thu, 28 -0000 From: "Asante, Emmanuel A" To: Dear Terry, I have been asked by Professor Collinge to respond to a Senior Scientist in the MRC Prion Unit and the lead paper. I have attached a pdf copy of the paper for your you for your interest in the paper. In respect of your first question, the simple answer will find in the paper, we have managed to associate phenotype to type 2 PrPSc, the commonest sporadic CJD. It is too early to be able to claim any further respect of Heidenhain variant CJD or Vicky Rimmer's take further studies, which are on-going, to establish sub-types to our initial finding which we are now point of the paper is that, as well as leading to the variant CJD phenotype, BSE transmission to the can lead to an alternate phenotype which is 2 PrPSc. I hope reading the paper will enlighten you more on the can be of any further assistance please to not hesitate Emmanuel Asante <> ____________________________________ Dr. Emmanuel A Asante MRC Prion Unit & Neurogenetics College School of Medicine (St. Mary's) Norfolk Place, Tel: +44 (0)20 7594 3794 Fax: +44 (0)20 7706 3272 email: e.asante@ic.ac.uk (until 9/12/02) New e-mail: e.asante@prion.ucl.ac.uk (active from now) ____________________________________TSS Valine 129 Prevents Expression of Variant CJD Phenotype Melanie Desbruslais, Jacqueline M. Linehan, Susan Joiner, Ian Gowland, Julie Welch, Lisa Stone, Sarah E. Lloyd, Andrew F. Hill,* Sebastian Brandner, John Collinge. Variant Creutzfeldt-Jakob disease (vCJD) is a unique clinicopathological and molecular phenotype of human associated with infection with bovine spongiform prions. Here, we found that generation of this required expression of human prion protein (PrP) with Expression of human PrP with valine 129 resulted in a remarkably, persistence of a barrier to transmission of subpassage. Polymorphic residue 129 of human PrP distinct prion strains after BSE prion infection. Thus, human infection with BSE-derived prions may result in novel phenotypes in addition to vCJD, depending on the source and the recipient. derived from bovine spongiform encephalopathy transmissions to inbred mice Susan Joiner, Jennifer Buckell, Sebastian Brandner, Jonathan D. F. Wadsworth and John Collinge Correspondence John Collinge j.collinge@prion.ucl.ac.uk MRC Prion Unit and Department of Neurodegenerative University College, London WC1N 3BG, UK Received 9 December 2003 Accepted 27 April 2004 Distinct prion strains can be distinguished by and biochemical properties of disease-associated prion Reliable comparisons of mouse prion strain properties genetically identical mice, as host prion protein to modulate prion disease phenotypes. While multiple sheep scrapie and Creutzfeldt-Jakob disease, bovine thought to be caused by a single prion strain. Primary of inbred mice resulted in the propagation of two prion strains may have been isolated. To investigate subpassaged in a single line of inbred mice (SJL) and strains had been identified. MRC1 was characterized by a mono-glycosylated-dominant PrPSc type and a deposits, while MRC2 displayed a much longer incubation a di-glycosylated-dominant PrPSc type and a distinct and neuronal loss. These data indicate a crucial prion strain selection and propagation in mice. It is may also be possible in BSE prion infection in humans Medical Sciences Cristina Casalone *, Gianluigi Zanusso , Pierluigi *Centro di Referenza Nazionale per le Encefalopatie Transmissible spongiform encephalopathies (TSEs), or -------------------------------------------------------------------------------- C.C. and G.Z. contributed equally to this work. ||To whom correspondence should be addressed. E-mail: salvatore.monaco@mail.univr.it . www.pnas.org/cgi/doi/10.1073/pnas.0305777101 of CJD brains was initially demonstrated in primates classification of atypical cases as CJD was based on (28). To date, no systematic studies of strain typing been provided, and classification of different subtypes on clinical, neuropathological, and molecular features PRNP codon 129 and the PrPSc glycotype) (8, 9, 15, 19). The importance of molecular PrPSc characterization in the identity of TSE strains is underscored by several showing that the stability of given disease-specific maintained upon experimental propagation of sCJD, familial CJD, and vCJD isolates in transgenic PrP-humanized mice (8, 29). Similarly, biochemical properties of BSE- and PrPSc molecules remain stable after passage to mice expressing bovine PrP (30). Recently, however, it has been reported that PrP-humanized mice inoculated with BSE may also propagate a distinctive PrPSc type, with a dominant'' pattern and electrophoretic mobility of the unglycosylated fragment slower than that of vCJD and Strikingly, this PrPSc type shares its molecular a PrPSc molecule found in classical sCJD. This variance with the PrPSc type found in MV2 sCJD cases and in cattle BASE, showing a monoglycosylated-dominant faster electrophoretic mobility of the as compared with BSE. In addition to molecular properties of PrPSc, BASE and MV2 sCJD share a distinctive pattern of intracerebral PrP deposition, which occurs as amyloid-kuru plaques. Differences were, however, the regional distribution of PrPSc. While inMV2 sCJD largest amounts of PrPSc were detected in the cerebellum, brainstem, and striatum, in cattle BASE these areas involved and the highest levels of PrPSc were recovered thalamus and olfactory regions. In conclusion, decoding the biochemical PrPSc signature of individual human and animal TSE strains may allow the of potential risk factors for human disorders with unknown etiology, such as sCJD. However, although BASE and sCJD share several characteristics, caution is dictated a link between conditions affecting two different mammalian species, based on convergent biochemical properties of PrPSc types. Strains of TSE agents may be better characterized upon passage to transgenic mice. In the until this is accomplished, our present findings epidemiological surveillance of cattle TSE and sCJD molecular criteria. [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirement for the Disposition of Non-Ambulatory Disabled Cattle 03-025IFA From: Terry S. Singeltary Sr. [flounder9@verizon.net] Sent: Thursday, September 08, 2005 6:17 PM To: fsis.regulationscomments@fsis.usda.gov Subject: [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirements for the Disposition of Non-Ambulatory Disabled Cattle Greetings FSIS, I would kindly like to submit the following to [Docket No. 03-025IFA] FSIS Prohibition of the Use of Specified Risk Materials for Human Food and Requirements for the Disposition of Non-Ambulatory Disabled Cattle THE BSE/TSE SUB CLINICAL Non-Ambulatory Disabled Cattle Broken bones and such may be the first signs of a sub clinical BSE/TSE Non-Ambulatory Disabled Cattle ; SUB CLINICAL PRION INFECTION MRC-43-00 Issued: Monday, 28 August 2000 NEW EVIDENCE OF SUB-CLINICAL PRION INFECTION: IMPORTANT RESEARCH FINDINGS RELEVANT TO CJD AND BSE P.O. Box 42 Bacliff, Texas USA 77518 9/13/2005 PLEASE SEE FLAMING EVIDENCE THAT THE USDA ET AL COVERED UP MAD COW DISEASE http://www.usda.gov/oig/webdocs/50601-10-KC.pdf http://www.usda.gov/oig/webdocs/50601-10-KC.pdf TSS
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