Characterization of tau prion seeding activity and strains from formaldehyde-fixed tissue

• Sarah K. Kaufman,
• Talitha L. Thomas,
• Kelly Del Tredici,
• Heiko Braak and
• Marc I. DiamondEmail author

Acta Neuropathologica CommunicationsNeuroscience of Disease20175:41

DOI: 10.1186/s40478-017-0442-8

©  The Author(s). 2017

Received: 11 May 2017

Accepted: 11 May 2017

Published: 7 June 2017

Abstract

Tauopathies such as Alzheimer’s disease (AD) feature progressive intraneuronal deposition of aggregated tau protein. The cause is unknown, but in experimental systems trans-cellular propagation of tau pathology resembles prion pathogenesis. Tau aggregate inoculation into mice produces transmissible pathology, and tau forms distinct strains, i.e. conformers that faithfully replicate and create predictable patterns of pathology in vivo. The prion model predicts that tau seed formation will anticipate neurofibrillary tau pathology. To test this idea requires simultaneous assessment of seed titer and immunohistochemistry (IHC) of brain tissue, but it is unknown whether tau seed titer can be determined in formaldehyde-fixed tissue. We have previously created a cellular biosensor system that uses flow cytometry to quantify induced tau aggregation and thus determine seed titer. In unfixed tissue from PS19 tauopathy mice that express 1 N,4R tau (P301S), we have measured tau seeding activity that precedes the first observable histopathology by many months. Additionally, in fresh frozen tissue from human AD subjects at early to mid-neurofibrillary tangle stages (NFT I-IV), we have observed tau seeding activity in cortical regions predicted to lack neurofibrillary pathology. However, we could not directly compare the same regions by IHC and seeding activity in either case. We now describe a protocol to extract and measure tau seeding activity from small volumes (.04 mm3) of formaldehyde-fixed tissue immediately adjacent to that used for IHC. We validated this method with the PS19 transgenic mouse model, and easily observed seeding well before the development of phospho-tau pathology. We also accurately isolated two tau strains, DS9 and DS10, from fixed brain tissues in mice. Finally, we have observed robust seeding activity in fixed AD brain, but not controls. The successful coupling of classical IHC with seeding and strain detection should enable detailed study of banked brain tissue in AD and other tauopathies.

snip...

Discussion

Propagation of tau aggregation along neuronal networks may mediate the progressive accumulation of pathology observed in tauopathy patients. To measure tau seeding activity in well-characterized human brains, it will be necessary to analyze formaldehyde-fixed tissues. We now present a method for extracting tau seeding activity from miniscule amounts of fixed tissue (approximately .04 mm3) to permit direct comparison with tissues stained by IHC.

We first tested this method in PS19 mice that overexpress full-length human tau (1 N,4R) containing the P301S mutation. We drop-fixed brain samples that had been embedded either in paraffin or PEG and sectioned them coronally for microscopy. We analyzed adjacent 50 μm sections using standard IHC to detect phospho-tau or 1 mm circular punch biopsies of tissue for seeding assays. We homogenized punch biopsies by water-bath sonication in closed tubes, and assayed them in a cellular FRET bioassay system as described previously [10, 13].

Tau seeding activity tracked the development of pathology more efficiently than IHC, with a lower degree of inter-animal variation, and a higher dynamic range. This was perfectly comparable to previously obtained results using fresh frozen tissue [13]. In addition, we detected seeding activity relatively early in the course of disease (1–2 months) and it steadily increased over time. Next, we tested brain tissues from animals previously inoculated with two distinct tau prion strains. We recovered these strains from fixed mouse brain tissue as accurately as we had previously from fresh frozen tissue. Finally, we tested the extraction method in fixed human brain tissue with documented AT8-positive tau pathology, including AD, and readily detected tau seeding activity in cases archived for up to 27 years in formaldehyde.

Seeding activity

Our laboratory previously detected tau seeding activity in fresh frozen brain tissue from mouse tauopathy models and human AD cases[11, 13]. However, fresh frozen samples are much more difficult to obtain than fixed tissue sections, must be carefully stored at−80 °C, and are very challenging to dissect precisely to isolate specific brain regions. The assay described here accurately quantifies tau seeding from fixed tissue sections over three log orders of signal. Remarkably, in a mouse model from which we sampled tissue at different time points, fixed tissue seeding proved comparable to seeding activity detected in fresh frozen tissue. Thus, we expect that this assay will enable assessment of tau seeding activity in a range of fixed tissues at a similar level of sensitivity to fresh frozen samples.

Moreover, we detected seeding activity in a small sample of human tauopathy cases that were collected and stored in formalin for over 20 years prior to this study. We observed lower seeding activity in these human samples than in PS19 mice, probably because of the overexpression of an aggregation-prone form of tau in this mouse model. However, the length of fixation may affect the level of seeding observed in samples. Further, differences in seeding activity observed between patients at Braak stage III and V likely reflect differences in the level of tau aggregate burden between these patients, cell loss, or ghost-tangle formation at later disease stages. Given the early detection of seeding activity relative to AT8 staining in PS19 mice, we anticipate that this assay could represent a more sensitive metric of tau pathology. Additional studies in a large number of well-characterized human tissue samples will help address these important questions, and provide additional insight into the progression of seeding activity in human tauopathies.

Earlier work described a dose-dependent increase in tau seeding activity in the PS19 mouse tauopathy model [13]. However, the regional specificity possible with fresh frozen tissue was limited to gross dissection. We now have reliably isolated and characterized punch biopsies as small as 1 mm diameter x 50 μm (or ~ .04 mm3). When we quantified the level of seeding activity at increasing ages vs. the tau pathology observed in adjacent tissue slices using anti-tau AT8 staining, we easily detected tau seeding activity, even in fixed tissue sections with a minimal AT8 signal. For example, when PS19 mice were inoculated with tau strains, we induced strong AT8 pathology with DS9, whereas DS10 produced a weak signal. In both cases, the pathology spread from the site of inoculation to connected regions, as described elsewhere [22]. The fixed tissue seeding assay more readily detected the spread of tau pathology in this propagation model. Furthermore, we readily detected seeding activity in DS10 inoculated mice despite the relatively subtle AT8 staining phenotype induced by this strain (mossy fiber dots). Consequently seeding activity can serve as an important measure of tau pathology when routine AT8 staining reports otherwise minimal pathology. The combination of precise quantification of seeding activity with the ability to sample brain tissue to 1 mm resolution indicates that this method could help define the seeding activity in human brain with remarkably high accuracy.

Detection of tau strains in formaldehyde-fixed tissue

Prior experimental work indicates that distinct tau aggregate conformations may underlie different patterns of pathology, rates of progression, and disease phenotypes observed in distinct tauopathies [2, 7, 22]. Distinct tau strains are associated with different tauopathies [22], and inoculation of unique tau strains produces different patterns and tau pathology rates of progression [16]. We observed that fixed tissue from mice inoculated with DS9 and DS10 produced strain phenotypes identical to the original strains upon inoculation into LM1 biosensor cells. Thus, tau strains are stable upon fixation. We anticipate that formaldehyde-fixed tissues will serve as an invaluable resource to examine the role of strain composition in tauopathies.

Studies that use traditional IHC techniques to detect tau pathology have provided important insights into the progression and anatomy of macromolecular accumulations of tau assemblies. However, these methods cannot discriminate among distinct strains, nor can they detect submicroscopic tau assemblies. The present assay measures tau pathology based on seeding activity and is also sensitive to strain composition. We anticipate that punch biopsies taken from tissue sections will be useful to measure strain identity with high anatomical precision. By carefully comparing seeding activity and strain composition with standard neuropathology, it should be possible to add new dimensions to analyses of tissue samples from a range of neurodegenerative diseases. In turn, this will facilitate more widespread testing of the putative role of tau prion activity in human tauopathies.

snip...see full text ;

https://actaneurocomms.biomedcentral.com/articles/10.1186/s40478-017-0442-8

http://tauopathies.blogspot.com/2016/12/tau-prions-from-alzheimers-disease-and.html

http://tauopathies.blogspot.com/

http://betaamyloidcjd.blogspot.com/

http://vpspr.blogspot.com/

http://transmissiblespongiformencephalopathy.blogspot.com/

http://chronic-wasting-disease.blogspot.com/

http://scrapie-usa.blogspot.com/

http://bse-atypical.blogspot.com/

http://bovineprp.blogspot.com/

http://transmissible-mink-encephalopathy.blogspot.com/

http://creutzfeldt-jakob-disease.blogspot.com/

Terry S. Singeltary Sr.

Tau prions from Alzheimer’s disease and chronic traumatic encephalopathy patients propagate in cultured cells

1. Amanda L. Woerman^a,^b,¹,
2. Atsushi Aoyagi^a,^c,¹,
3. Smita Patel^a,
4. Sabeen A. Kazmi^a,
5. Iryna Lobach^d,
6. Lea T. Grinberg^b,^e,
7. Ann C. McKee^f,^g,^h,ⁱ,^j,
8. William W. Seeley^b,^e,
9. Steven H. Olson^a,^b, and
10. Stanley B. Prusiner^a,^b,^k,²

Author Affiliations

1. ^aInstitute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, CA 94143;
2. ^bDepartment of Neurology, University of California, San Francisco, CA 94143;
3. ^cDaiichi Sankyo Co., Ltd., Tokyo 140-8710, Japan;
4. ^dDepartment of Epidemiology and Biostatistics, University of California, San Francisco, CA 94143;
5. ^eDepartment of Pathology, University of California, San Francisco, CA 94143;
6. ^fChronic Traumatic Encephalopathy Program, Alzheimer’s Disease Center, Boston University School of Medicine, Boston, MA 02118;
7. ^gDepartment of Neurology, Boston University School of Medicine, Boston, MA 02118;
8. ^hDepartment of Pathology, Boston University School of Medicine, Boston, MA 02118;
9. ⁱVeterans Affairs Boston Healthcare System, US Department of Veterans Affairs, Jamaica Plain, MA 02130;
10. ^jUS Department of Veterans Affairs Medical Center, Bedford, MA 01730;
11. ^kDepartment of Biochemistry and Biophysics, University of California, San Francisco, CA 94143

1. Contributed by Stanley B. Prusiner, October 6, 2016 (sent for review August 5, 2016; reviewed by Robert H. Brown Jr. and David Westaway)

1. Abstract
2. Full Text
3. Authors & Info
4. Figures
5. SI
6. Metrics
7. Related Content
8. PDF
9. PDF + SI

Significance

The progressive nature of neurodegenerative diseases is due to the spread of prions, misfolded infectious proteins, in the brain. In tauopathies, the protein tau misfolds, causing several diseases, including Alzheimer’s disease (AD) and chronic traumatic encephalopathy (CTE). Here we created a panel of mammalian cell lines expressing a fragment of tau fused to yellow fluorescent protein. Each cell line selectively detects tau prions that are misfolded into self-propagating conformations; such cells permit identification of minute differences among tauopathies. For example, tau prions in AD and CTE are distinct from prions in other tauopathies such as Pick’s disease and progressive supranuclear palsy. These insights are likely to contribute to the development of future therapeutics.

Abstract

Tau prions are thought to aggregate in the central nervous system, resulting in neurodegeneration. Among the tauopathies, Alzheimer’s disease (AD) is the most common, whereas argyrophilic grain disease (AGD), corticobasal degeneration (CBD), chronic traumatic encephalopathy (CTE), Pick’s disease (PiD), and progressive supranuclear palsy (PSP) are less prevalent. Brain extracts from deceased individuals with PiD, a neurodegenerative disorder characterized by three-repeat (3R) tau prions, were used to infect HEK293T cells expressing 3R tau fused to yellow fluorescent protein (YFP). Extracts from AGD, CBD, and PSP patient samples, which contain four-repeat (4R) tau prions, were transmitted to HEK293 cells expressing 4R tau fused to YFP. These studies demonstrated that prion propagation in HEK cells requires isoform pairing between the infecting prion and the recipient substrate. Interestingly, tau aggregates in AD and CTE, containing both 3R and 4R isoforms, were unable to robustly infect either 3R- or 4R-expressing cells. However, AD and CTE prions were able to replicate in HEK293T cells expressing both 3R and 4R tau. Unexpectedly, increasing the level of 4R isoform expression alone supported the propagation of both AD and CTE prions. These results allowed us to determine the levels of tau prions in AD and CTE brain extracts.

• argyrophilic grain disease
• corticobasal degeneration
• Pick’s disease
• progressive supranuclear palsy
• tauopathies

Footnotes

• ↵¹A.L.W. and A.A. contributed equally to this work.
• ↵²To whom correspondence should be addressed. Email: stanley.prusiner@ucsf.edu.

• Author contributions: A.L.W., A.A., S.H.O., and S.B.P. designed research; A.L.W., A.A., S.P., S.A.K., and L.T.G. performed research; I.L., L.T.G., A.C.M., and W.W.S. contributed new reagents/analytic tools; A.L.W., A.A., S.P., I.L., S.H.O., and S.B.P. analyzed data; and A.L.W., A.A., S.H.O., and S.B.P. wrote the paper.
• Reviewers: R.H.B., University of Massachusetts Medical School; and D.W., University of Alberta.
• Conflict of interest statement: A provisional patent application has been submitted in connection with this work. Inventors include A.L.W., A.A., S.P., S.A.K., S.H.O., and S.B.P.
• This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1616344113/-/DCSupplemental.

http://www.pnas.org/content/early/2016/11/22/1616344113.abstract

The Prion Institute focuses on the following areas of research excellence: protein folding and misfolding; pathobiology of TSEs; surveillance and control; and TSEs and society. 

 

Applications must be submitted through the Agriculture Funding Consortium website.

 

ALBERTA ALZHEIMER RESEARCH PROGRAM

 

The Alberta Prion Research Institute (Prion Institute) and the Alzheimer Society of Alberta and Northwest Territories (ASANT) present the Alberta Alzheimer Research Program (AARP). The AARP allows qualified Alberta investigators to seek funding for research directly related to Alzheimer’s disease in areas related to understanding the fundamental mechanisms of the disease and/or improving the quality of life of those with Alzheimer’s disease. There are two streams for grants: Young Investigator Grants and Regular Research Grants. Young Investigator Grants are available to Alberta researchers who are within five years of their first appointment after completing their research training. These grants are for up to $200,000 with a term of up to three years. Regular Research Grants are available to all Alberta researchers, including young investigators. These grants are for up to $150,000 with a term of up to three years.

Application Deadline: January 16, 2017

 

Program Guidelines

Funding Declaration

Budget Spreadsheet

 

EXPLORATIONS

The Explorations Program allows Alberta-based investigators to seek funding for research directly related to prion diseases and prion-like human neurodegenerative diseases and dementias. The research themes for this program are protein folding and misfolding in prion diseases, the pathobiology of transmissible spongiform encephalopathies (TSEs), surveillance and control of prion diseases, TSEs and society, protein folding and misfolding in prion-like human neurodegenerative diseases, and prion-like mechanisms in human neurodegenerative diseases. The Alberta Prion Research Institute offers two tiers of funding for the Explorations competition: grants of up to $200,000 for a maximum of two years and grants of up to $500,000 for a maximum of three years.

Application Deadline: no current competition

SPECIFIED RISK MATERIALS PROGRAM

The Specified Risk Materials Program is intended to allow qualified investigators to seek funding for research directly related to the following areas of specified risk materials (SRM): detection of prions in complex matrices; SRM as feedstock for processes and products; disposition and disposal methods; cost benefit estimates of existing or new disposition and disposal methodologies; risk assessment; risk communication about SRM and risks and benefits of disposition and disposal of SRM; and other. Funding is accessible for all relevant fields of inquiry in the themes as described in the guideline to develop innovative disposition and disposal methods and/or uses of specified risk materials. This competition will support grants of up to $500,000 for a period of up to three years. 

Application Deadline: no current competition

 

 RESEARCH TEAM PROGRAM
 

The Research Team Program allows teams of qualified investigators to seek funding for research directly related to prion diseases and prion-like human neurodegenerative diseases and dementias. The research themes for this program are protein folding and misfolding in prion diseases, the pathobiology of TSEs, surveillance and control of prion diseases, TSEs and society, protein folding and misfolding in prion-like human neurodegenerative diseases and prion-like mechanisms in the pathobiology of prion-like human neurodegenerative diseases. The program is designed to encourage collaboration within Alberta and between Alberta-based investigators and researchers outside of Alberta. The team of researchers must be from at least two different research institutions. The Alberta Prion Research Institute provides up to $750,000 for a team grant over a maximum of three years.

Application Deadline: no current competition

 IDeal PROGRAM

 

 The IDeal Program, also known as the Innovation and Delivery Program, was created to encourage collaboration among industry, Alberta universities and research institutions. The Alberta Prion Research Institute invites applications for research and development projects undertaken by Alberta-based private sector organizations or public sector researchers and their private sector partners. A private sector partner may be a company, an industry association or similar body. Direct project costs are shared by private sector partners and the funders. IDeal grants are typically of an applied nature and directed at a specific challenge identified by the private sector partner and the industry. Themes accessible for funding are:

• Protein folding and misfolding in prion diseases;
• The pathobiology of TSEs;
• Surveillance and control of prion diseases;
• Diagnostic technologies;
• Solutions to enhance market access;
• Innovative disposal and/or uses of specified risk material;
• TSEs and society;
• Protein folding and misfolding in prion-like human neurodegenerative diseases; and
• Prion-like mechanisms in human neurodegenerative diseases.
   

Funding may be up to $500,000. Projects may range from one to three years in duration.

Application Deadline: continuous intake

GUEST SPEAKER SUPPORT PROGRAM
 

The Guest Speaker Support Program is designed to disseminate knowledge to the Alberta research and science community by offering funding to help bring notable researchers in prion and protein misfolding science to Alberta to present lectures and to participate in panel discussions. These experts assist with planning or implementing collaborative research programs and/or explore and evaluate recent breakthroughs in prion science. Speakers might be involved in research related activities or public studies or both. Funds are provided primarily to offset the costs of travel and accommodation for guest speakers. Support of up to $1,500 is provided for speakers travelling within North America, and up to $2,500 is provided for speakers travelling from outside North America. In some cases, the Alberta Prion Research Institute will consider application for a contribution toward the cost of conducting an associated conference, symposia or workshop.

Application Deadline: continuous intake

 

EXPANDING HORIZONS PROGRAM

 

The Expanding Horizons Program is a professional development program for graduate students and postdoctoral fellows who are currently working on prion research. The objective of this program is to provide research trainees with access to mentoring in order to develop skills and knowledge that are applicable both within and outside of the lab. Seminars focus on career development in research as well as other careers they might undertake such as those in industry or policy making. Ensuring trainees are skilled in topics like lab management, networking, communicating, interview skills and grant crafting will benefit their futures as well as the future of prion research.

http://prioninstitute.ca/content/programs

Self-Propagative Replication of Ab Oligomers Suggests Potential Transmissibility in Alzheimer Disease

*** Singeltary comment PLoS ***

Alzheimer’s disease and Transmissible Spongiform Encephalopathy prion disease, Iatrogenic,

what if ?

Posted by flounder on 05 Nov 2014 at 21:27 GMT

http://www.plosone.org/annotation/listThread.action?root=82860

Sunday, November 22, 2015

*** Effect of heating on the stability of amyloid A (AA) fibrils and the intra- and cross-species transmission of AA amyloidosis Abstract

Amyloid A (AA) amyloidosis is a protein misfolding disease characterized by extracellular deposition of AA fibrils. AA fibrils are found in several tissues from food animals with AA amyloidosis. For hygienic purposes, heating is widely used to inactivate microbes in food, but it is uncertain whether heating is sufficient to inactivate AA fibrils and prevent intra- or cross-species transmission. We examined the effect of heating (at 60 °C or 100 °C) and autoclaving (at 121 °C or 135 °C) on murine and bovine AA fibrils using Western blot analysis, transmission electron microscopy (TEM), and mouse model transmission experiments. TEM revealed that a mixture of AA fibrils and amorphous aggregates appeared after heating at 100 °C, whereas autoclaving at 135 °C produced large amorphous aggregates. AA fibrils retained antigen specificity in Western blot analysis when heated at 100 °C or autoclaved at 121 °C, but not when autoclaved at 135 °C. Transmissible pathogenicity of murine and bovine AA fibrils subjected to heating (at 60 °C or 100 °C) was significantly stimulated and resulted in amyloid deposition in mice. Autoclaving of murine AA fibrils at 121 °C or 135 °C significantly decreased amyloid deposition. Moreover, amyloid deposition in mice injected with murine AA fibrils was more severe than that in mice injected with bovine AA fibrils. Bovine AA fibrils autoclaved at 121 °C or 135 °C did not induce amyloid deposition in mice. These results suggest that AA fibrils are relatively heat stable and that similar to prions, autoclaving at 135 °C is required to destroy the pathogenicity of AA fibrils. These findings may contribute to the prevention of AA fibril transmission through food materials to different animals and especially to humans.

Purchase options Price * Issue Purchase USD 511.00 Article Purchase USD 54.00

http://www.tandfonline.com/doi/abs/10.3109/13506129.2015.1095735?journalCode=iamy20

http://betaamyloidcjd.blogspot.com/2015/11/effect-of-heating-on-stability-of.html

 

SWISS MEDICAL WEEKLY

Alzheimer-type brain pathology may be transmitted by grafts of dura mater 26/01/2016 Singeltary comment ;

http://blog.smw.ch/alzheimer-type-brain-pathology-may-be-transmitted-by-grafts-of-dura-mater/#comment-89016

re-Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy

Nature 525, 247?250 (10 September 2015) doi:10.1038/nature15369 Received 26 April 2015 Accepted 14 August 2015 Published online 09 September 2015 Updated online 11 September 2015 Erratum (October, 2015)

snip...see full Singeltary Nature comment here;

http://www.nature.com/nature/journal/v525/n7568/full/nature15369.html#/comments

 

Sunday, December 04, 2016

Heidenhain variant of Creutzfeldt–Jakob disease in a patient who had bovine bioprosthetic valve implantation

Year : 2016 | Volume : 64 | Issue : 10 | Page : 767-769

http://creutzfeldt-jakob-disease.blogspot.com/2016/12/heidenhain-variant-of-creutzfeldtjakob.html

Thursday, December 1, 2016

PRION2017 DECIPHERING NEURODEGENERATIVE DISORDERS 23 – 26 May 2017 Edinburgh

http://prionprp.blogspot.com/2016/12/prion2017-deciphering-neurodegenerative.html

Saturday, December 03, 2016

TEXAS CHRONIC WASTING DISEASE CWD TSE PRION UPDATE 35 CASES TO DATE

http://chronic-wasting-disease.blogspot.com/2016/12/texas-chronic-wasting-disease-cwd-tse.html

Thursday, December 1, 2016

 

The European Union summary report on data of the surveillance of ruminants for the presence of transmissible spongiform encephalopathies (TSEs) in 2015

 

http://transmissiblespongiformencephalopathy.blogspot.com/2016/12/the-european-union-summary-report-on.html

 

 

Tuesday, November 29, 2016

 

Transmissibility of Gerstmann–Sträussler–Scheinker syndrome in rodent models: new insights into the molecular underpinnings of prion infectivity

 

http://transmissiblespongiformencephalopathy.blogspot.com/2016/11/transmissibility-of-gerstmannstraussler.html

 

Saturday, July 23, 2016

BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION SURVEILLANCE, TESTING, AND SRM REMOVAL UNITED STATE OF AMERICA UPDATE JULY 2016

http://bovineprp.blogspot.com/2016/07/bovine-spongiform-encephalopathy-bse.html

Tuesday, July 26, 2016

Atypical Bovine Spongiform Encephalopathy BSE TSE Prion UPDATE JULY 2016

http://bse-atypical.blogspot.com/2016/07/atypical-bovine-spongiform.html
 

*** Calling Canadian beef unsafe is like calling your twin sister ugly," Dopp said.

Thursday, August 25, 2016

*** FSIS Green Bay Dressed Beef Recalls Beef Products Due To Possible Specified Risk Materials Contamination the most high risk materials for BSE TSE PRION AKA MAD COW TYPE DISEASE ***

http://specifiedriskmaterial.blogspot.com/2016/08/fsis-green-bay-dressed-beef-recalls.html

Tuesday, August 9, 2016

*** Concurrence with OIE Risk Designations for Bovine Spongiform Encephalopathy [Docket No. APHIS-2015-0055]

http://bovineprp.blogspot.com/2016/08/concurrence-with-oie-risk-designations.html

Monday, May 02, 2016

*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***

http://chronic-wasting-disease.blogspot.com/2016/05/zoonotic-potential-of-cwd-prions-update.html

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
 

 why do we not want to do TSE transmission studies on chimpanzees $

5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

 snip...

 R. BRADLEY

http://collections.europarchive.org/tna/20080102222950/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf


http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160


SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20  

http://scrapie-usa.blogspot.com/2016/04/scrapie-ws-01-prion-diseases-in-animals.html

 *** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.

 *** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.

 *** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.

 http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160


 O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations

 Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France

 Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.

 *** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,

 ***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),

 ***is the third potentially zoonotic PD (with BSE and L-type BSE),

 ***thus questioning the origin of human sporadic cases. We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.

 ===============

***thus questioning the origin of human sporadic cases***

 ***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.

https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf
 

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

To the Editor: In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.

Terry S. Singeltary, Sr Bacliff, Tex

1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323.

http://jama.jamanetwork.com/article.aspx?articleid=1031186

26 March 2003

Terry S. Singeltary, retired (medically) CJD WATCH

I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al [1] have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey by intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc?

http://www.neurology.org/content/60/2/176/reply#neurology_el_535

Sent: Monday, January 08,2001 3:03 PM

TO: freas@CBS5055530.CBER.FDA.GOV

FDA CJD BSE TSE Prion Scientific Advisors and Consultants Staff January 2001 Meeting Singeltary Submission

2001 FDA CJD TSE Prion Singeltary Submission

http://www.fda.gov/ohrms/dockets/ac/01/slides/3681s2_09.pdf

2 January 2000

British Medical Journal

U.S. Scientist should be concerned with a CJD epidemic in the U.S., as well

http://www.bmj.com/rapid-response/2011/10/28/us-scientist-should-be-concerned-cjd-epidemic-us-well

15 November 1999

British Medical Journal

vCJD in the USA * BSE in U.S.

http://www.bmj.com/rapid-response/2011/10/28/re-vcjd-usa-bse-us ;;;

 

Monday, December 5, 2016

Prion Institute protein folding and misfolding; pathobiology of TSEs; surveillance, control; and TSEs

http://prionprp.blogspot.com/2016/12/prion-institute-protein-folding-and.html

Sunday, December 04, 2016

Heidenhain variant of Creutzfeldt–Jakob disease in a patient who had bovine bioprosthetic valve implantation

Year : 2016 | Volume : 64 | Issue : 10 | Page : 767-769

http://creutzfeldt-jakob-disease.blogspot.com/2016/12/heidenhain-variant-of-creutzfeldtjakob.html

Tuesday, November 29, 2016

 

Transmissibility of Gerstmann–Sträussler–Scheinker syndrome in rodent models: new insights into the molecular underpinnings of prion infectivity

 

http://transmissiblespongiformencephalopathy.blogspot.com/2016/11/transmissibility-of-gerstmannstraussler.html

 

Terry S. Singeltary Sr.

Bacliff, Texas USA 77518

<flounder9@verizon.net>