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From: TSS ()
Greetings BSE-L, An interesting slide show by Prof Ralph J. Blanchfield. I thought some might be interested in this slide show. BSE/vCJD The European Ongoing Story Prof J Ralph Blanchfield, MBE Creutzfeldt-Jakob disease Magdalini Polymenidou, Katharina Stoeck, Markus Glatzel, Martin Vey, Anne Bellon, and Adriano Aguzzi Summary Background The molecular typing of sporadic Creutzfeldt-Jakob disease (CJD) is based on the size and glycoform ratio of protease-resistant prion protein (PrPSc), and on PRNP haplotype. On digestion with proteinase K, type 1 and type 2 PrPSc display unglycosylated core fragments of 21 kDa and 19 kDa, resulting from cleavage around amino acids 82 and 97, respectively. Methods We generated anti-PrP monoclonal antibodies to epitopes immediately preceding the differential proteinase K cleavage sites. These antibodies, which were designated POM2 and POM12, recognise type 1, but not type 2, PrPSc. Findings We studied 114 brain samples from 70 patients with sporadic CJD and three patients with variant CJD. Every patient classified as CJD type 2, and all variant CJD patients, showed POM2/POM12 reactivity in the cerebellum and other PrPSc-rich brain areas, with a typical PrPSc type 1 migration pattern. Interpretation The regular coexistence of multiple PrPSc types in patients with CJD casts doubts on the validity of electrophoretic PrPSc mobilities as surrogates for prion strains, and questions the rational basis of current CJD 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? Subject: PrPSc distribution of a natural case of bovine spongiform encephalopathy Date: August 8, 2005 at 12:28 pm PST PrPSc distribution of a natural case of bovine spongiform encephalopathy Yoshifumi Iwamaru, Yuka Okubo, Tamako Ikeda, Hiroko Hayashi, Mori- kazu Imamura, Takashi Yokoyama and Morikazu Shinagawa Priori Disease Research Center, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba 305-0856 Japan gan@affrc.go.jp Abstract Bovine spongiform encephalopathy (BSE) is a disease of cattle that causes progressive neurodegeneration of the central nervous system. Infectivity of BSE agent is accompanied with an abnormal isoform of prion protein (PrPSc). The specified risk materials (SRM) are tissues potentially carrying BSE infectivity. The following tissues are designated as SRM in Japan: the skull including the brain and eyes but excluding the glossa and the masse- ter muscle, the vertebral column excluding the vertebrae of the tail, spinal cord, distal illeum. For a risk management step, the use of SRM in both animal feed or human food has been prohibited. However, detailed PrPSc distribution remains obscure in BSE cattle and it has caused controversies about definitions of SRM. Therefore we have examined PrPSc distribution in a BSE cattle by Western blotting to reassess definitions of SRM. The 11th BSE case in Japan was detected in fallen stock surveillance. The carcass was stocked in the refrigerator. For the detection of PrPSc, 200 mg of tissue samples were homogenized. Following collagenase treatment, samples were digested with proteinase K. After digestion, PrPSc was precipitated by sodium phosphotungstate (PTA). The pellets were subjected to Western blotting using the standard procedure. Anti-prion protein monoclonal antibody (mAb) T2 conjugated horseradish peroxidase was used for the detection of PrPSc. PrPSc was detected in brain, spinal cord, dorsal root ganglia, trigeminal ganglia, sublingual ganglion, retina. In addition, PrPSc was also detected in the peripheral nerves (sciatic nerve, tibial nerve, vagus nerve). Our results suggest that the currently accepted definitions of SRM in 9/13/2005 179 Page 10 of 17 BSE cattle may need to be reexamined. T. Kitamoto (Ed.) PRIONS Food and Drug Safety November 2, 2004; Bovine spongiform encephalopathy (BSE) in Japan snip... "Furthermore, current studies into transmission of cases of BSE that are atypical or that develop in young cattle are expected to amplify the BSE prion" NO. Date conf. Farm Birth place and Date Age at diagnosis 8. 2003.10.6. Fukushima Tochigi 2001.10.13. 23 9. 2003.11.4. Hiroshima Hyogo 2002.1.13. 21 Test results # 8b, 9c cows Elisa Positive, WB Positive, IHC negative, histopathology negative b = atypical BSE case c = case of BSE in a young animal b,c, No PrPSc on IHC, and no spongiform change on histology International Symposium of Prion Diseases held in Sendai, October 31, to November 2, 2004. Tetsuyuki Kitamoto Professor and Chairman Department of Prion Research Tohoku University School of Medicine 2-1 SeiryoAoba-ku, Sendai 980-8575, JAPAN TEL +81-22-717-8147 FAX +81-22-717-8148 e-mail; kitamoto@mail.tains.tohoku.ac.jp Symposium Secretariat Kyomi Sasaki TEL +81-22-717-8233 FAX +81-22-717-7656 e-mail: kvomi-sasaki@mail.tains.tohoku.ac.ip [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 http://www.fsis.usda.gov/OPPDE/Comments/03-025IFA/03-025IFA-2.pdf As of August 31, 2005, there were 115 scrapie infected and source flocks (figure 3). There were 3 new infected and source flocks reported in August (Figure 4) with a total of 148 flocks reported for FY 2005 (Figure 5). The total infected and source flocks that have been released in FY 2005 are 102 (Figure 6), with 5 flocks released in August. The ratio of infected and source flocks released to newly infected and source flocks for FY 2005 = 0.69 : snip... full text ; p.s. please note the 47 PENDING CASES to Sept. 2005 p.s. please note the 2005 Prion D. total 120(8) 8=includes 51 type pending, 1 TYPE UNKNOWN ??? p.s. please note sporadic CJD 2002(1) 1=3 TYPE UNKNOWN??? p.s. please note 2004 prion disease (6) 6=7 TYPE UNKNOWN??? http://www.cjdsurveillance.com/resources-casereport.html CWD, scrapie TO HUMANS in USA = one of the six documented phenotypes of sCJD or cwdCJD or scrapieCJD ??? AS implied in the Inset 25 we must not _ASSUME_ that snip... http://www.bseinquiry.gov.uk/files/yb/1991/01/04004001.pdf ATYPICAL TSEs in USA CATTLE AND SHEEP ? http://www.bseinquiry.gov.uk/files/sc/seac17/tab03.pdf TSS #################### https://lists.aegee.org/bse-l.html ####################
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