Sunday, July 9, 2017

Scientists uncover the structure of tau filaments from Alzheimer's disease

Scientists uncover the structure of tau filaments from Alzheimer's disease

5 Jul 2017

Researchers at the MRC Laboratory of Molecular Biology (LMB) have, for the first time, revealed the atomic structures of one of the two types of the abnormal filaments which lead to Alzheimer's disease. Understanding the structures of these filaments will be key in developing drugs to prevent their formation.

The researchers, whose study is published today in Nature, believe the structures they have uncovered could also suggest how tau protein may form different filaments in other neurodegenerative diseases.

Alzheimer’s, the most common neurodegenerative disease, is characterised by the existence of two types of abnormal ‘amyloid’ forms of protein which form lesions in the brain. Tau forms filaments inside nerve cells and amyloid-beta forms filaments outside cells. Tau lesions appear to have a stronger correlation to the loss of cognitive ability in patients with the disease.

Almost thirty years ago, scientists at the LMB (including Michel Goedert, one of the senior authors on this paper) identified tau protein as an integral component of the lesions found in Alzheimer’s and a range of other neurodegenerative diseases. But, until now, scientists have been unable to identify the atomic structure of the filaments.

The researchers extracted tau filaments from the brain of a patient who had died with Alzheimer's disease. The filaments were then imaged using cryo-electron microscopy (cryo-EM). Senior author Sjors Scheres and colleagues developed new software in order to calculate the structure of the filaments in sufficient detail to deduce the arrangement of the atoms inside them.

Sjors Scheres said: “It’s very exciting that we were able to use this new technique to visualise filaments from a diseased brain as previous work depended on artificial samples assembled in the laboratory. Amyloid structures can form in many different ways, so it has been unclear how close these lab versions resembled those in human disease.

“Knowing which parts of tau are important for filament formation is relevant for the development of drugs. For example, many pharmaceutical companies are currently using different parts of tau in tests to measure the effect of different drugs on filament formation; this new knowledge should significantly increase the accuracy of such tests."

Fellow senior author Michel Goedert said: “We have known for almost three decades that the abnormal assembly of tau protein into filaments is a defining characteristic of Alzheimer's disease. In 1998, the dysfunction of tau protein was shown to be sufficient for neurodegeneration and dementia. In 2009, the prion-like properties of assembled tau were identified. These properties allow the abnormal form to convert previously normal forms.

“Until now the high-resolution structures of tau or any other disease-causing filaments from human brain tissue have remained unknown. This new work will help to develop better compounds for diagnosing and treating Alzheimer's and other diseases which involve defective tau.”

Dr Rob Buckle, chief science officer at the MRC, which funded the research, said: “This ground-breaking work is a major contribution to our understanding of Alzheimer's disease. Nearly thirty years ago scientists at the LMB were the first to discover that tau protein plays a key role in the disease. Knowing the basic structure of these filaments in diseased tissue is vital for the development of drugs to combat their formation.

“This research opens up new possibilities to study a range of other diseases where the accumulation of abnormal protein filaments plays a role, including Parkinson’s disease, motor neuron disease and prion diseases.”

The work was funded by the MRC, the European Union, US National Institutes of Health and the Department of Pathology and Laboratory Medicine, Indiana University School of Medicine.

https://www.mrc.ac.uk/news/browse/scientists-uncover-the-structure-of-tau-filaments-from-alzheimer-s-disease/

Cryo-EM structures of tau filaments from Alzheimer’s disease

Anthony W. P. Fitzpatrick, Benjamin Falcon, Shaoda He, Alexey G. Murzin, Garib Murshudov, Holly J. Garringer, R. Anthony Crowther, Bernardino Ghetti, Michel Goedert & Sjors H. W. Scheres

AffiliationsContributionsCorresponding authors Nature (2017) doi:10.1038/nature23002 Received 24 February 2017 Accepted 05 June 2017 Published online 05 July 2017 Article tools

Abstract

Abstract• Accession codes• References• Author information• Extended data figures and tables

Alzheimer’s disease is the most common neurodegenerative disease, and there are no mechanism-based therapies. The disease is defined by the presence of abundant neurofibrillary lesions and neuritic plaques in the cerebral cortex. Neurofibrillary lesions comprise paired helical and straight tau filaments, whereas tau filaments with different morphologies characterize other neurodegenerative diseases. No high-resolution structures of tau filaments are available. Here we present cryo-electron microscopy (cryo-EM) maps at 3.4–3.5 Å resolution and corresponding atomic models of paired helical and straight filaments from the brain of an individual with Alzheimer’s disease. Filament cores are made of two identical protofilaments comprising residues 306–378 of tau protein, which adopt a combined cross-β/β-helix structure and define the seed for tau aggregation. Paired helical and straight filaments differ in their inter-protofilament packing, showing that they are ultrastructural polymorphs. These findings demonstrate that cryo-EM allows atomic characterization of amyloid filaments from patient-derived material, and pave the way for investigation of a range of neurodegenerative diseases.

At a glance

snip...see images and more ;

https://www.nature.com/nature/journal/vaop/ncurrent/full/nature23002.html?sf95445996=1#acknowledgments

Neurodegeneration: Taming tangled tau

David S. Eisenberg & Michael R. Sawaya Affiliations Corresponding authors Nature (2017) doi:10.1038/nature23094

Published online 05 July 2017

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The protein tau forms abnormal filamentous aggregates called tangles in the brains of people with neurodegeneration. Structures of two such filaments offer pathways to a deeper understanding of Alzheimer's disease.

https://www.nature.com/nature/journal/vaop/ncurrent/full/nature23094.html

=====PRION 2017 CONFERENCE ABSTRACTS=====

P154 Development of an in vitro amplification assay for misfolded proteins in for misfolded proteins in Alzheimer’s diseases (AD) and Parkinson’s disease (PD)

Ms Susana Margarida Silva Correia1
1National Reference Center For Tse, Department Of Neurology, Georg-august University , Göttingen, Germany

A characteristic feature of major neurodegenerative diseases leading to dementia is the progressive accumulation of protein aggregates in the brain in a self-propagation-manner with a regional pattern specific to each disease. The concept of protein misfolding was initially thought to play a crucial role mainly in prion diseases, recent studies identified similar characteristics for amyloid beta, tau and alpha synuclein in various models. The term “prion-like“ protein propagation is now widely used to address the mechanisms which might play a role in amyloidopathies or tauopathies such as Alzheimer’s disease (AD) and alpha synucleinopathies, such as Parkinson’s disease (PD) or Lewy body dementia (LBD).

We established the RT-QuIC for the amplification of prion protein scrapie (PrPSc) in human brain tissue and cerebrospinal fluid (CSF) of CJD-patients (Schmitz M et al, 2016). The technique bears a huge diagnostic and analytical potential also for other misfolded proteins, which are showing a prion-like mechanism of protein misfolding.

The aim of the study is the implementation of the amyloid beta and alpha synuclein QuIC in diagnostic of neurodegenerative diseases. In particular, we aim to improve the diagnostic of AD, PD and LBD. The implementation of the amyloid beta and alpha synuclein QuIC in human disease diagnostic requires the analysis of a huge cohort of patients (available from our biobank) consisting of healthy controls, patients with alternative diagnosis as well as of patients with AD and PD.

The aim of the study is to develop the RT-QuIC to create a novel diagnostic-tests for other neurodegenerative diseases such as AD and PD. In a first step, we plan to produce recombinant amyloid beta and alpha synuclein and to test systematically different substrates in our QuIC-amplification assay. After validation of the most suitable substrates, we will applicate the RT-QuIC for the detection of amyloid beta and alpha synuclein aggregates in CSF from AD- and PD-patients.

=====

P188 Misfolded PrP is not always associated with formation of p-tau

Dr Debbie Brown1, Mr Declan King1, Dr Rona Barron1, Professor Pedro Piccardo1
1Roslin Institute, Edinburgh, United Kingdom

The conversion of cellular prion protein into a misfolded isoform is central to the development of prion diseases. Amyloid beta (Aβ) and hyperphosphorylated tau (p-tau) participate in the pathogenesis of Alzheimer´s disease (AD). Additionally several prion diseases in humans accumulate p-tau in the brain and therefore we hypothesise that proteins that participate in the pathogenesis of one disease may play a role in other disorders to establish complex proteinopathies, a mechanism that could explain the phenotypic variability observed in prion diseases. To explore this possibility we analysed p-tau accumulation in mouse models with varying degrees of PrP deposits in the brain. We used animals inoculated with :- mouse-adapted prion agents, typical and atypical bovine spongiform encephalopathy agents along with mice inoculated with wild-type (Wt) /mutant (101L) recombinant PrP fibrils and mice overexpressing 101L PrP. We observed that p-tau is consistently present in animals with prion infectivity (i.e. models that transmit disease upon serial passage). However, p-tau is not observed in non-prion mice inoculated with recombinant PrP fibrils or mice overexpressing PrP, both of which form large amyloid plaques in the absence of disease. The data suggest that p-tau is not necessarily associated with deposition of misfolded PrP, but that the interaction between the prion agent and host regulates the formation of p-tau and may contribute to the heterogeneous phenotype of prion diseases.

=====

P17 Induction of transmissible tau pathology by traumatic brain Injury

Dr Elisa R Zanier1, Ilaria Bertani1, Dr Maria Antonietta Chiaravalloti1, Dr Eliana Sammali1, Dr Francesca Pischiutta1, Dr Gloria Vegliante1, Dr Fabrizio Ortolano2, Dr Nino Stocchetti2,3, Dr Maria-Grazia De Simoni1, Dr Roberto Chiesa1
1Istituto di Ricerche Farmacologiche Mario Negri, Milano, Italy, 2Università degli Studi di Milano, Milano, Italy, 3Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico di Milano, Milano, Italy

Aims: The aim of this study was to test whether traumatic brain injury (TBI), a risk factor for Alzheimer’s disease and chronic traumatic encephalopathy, induces a tau pathology that spreads in the brain in a prion-like manner, causing functional and histopathological abnormalities.

Methods: C57BL/6J mice were subjected to focal TBI by single controlled cortical impact, and the presence of pathological tau was investigated by immunohistochemistry and Western blot using antibodies specific for different phosphorylated tau isoforms. The emergence of self-propagating tau isoform was investigated by inoculating 10% brain homogenates from TBI mice and humans into the brain of naïve C57BL/6J mice.

Results: Hyperphosphorylated tau was detected in the injured brain hemisphere at 3 months post-TBI, and in the ipsi and contralateral hemispheres at 12 months, indicating progressive spreading of tauopathy. Mice inoculated with TBI brain homogenates developed memory deficits detectable by the novel object recognition task at 4, 8 and 12 months after inoculation. Immunohistochemistry at 12 months post-inoculation showed hyperphosphorylated tau in the injected area and remote brain regions.

Conclusions: Results establish that a single focal TBI induces a tau pathology in wild-type mice that progressively spreads from the site of injury to other brain regions. They also show the emergence of self-propagating tau isoforms in the brains of TBI mice and humans, which can be transmitted to wild-type mice like bona fide prions, inducing memory dysfunction. These data suggest that inhibiting propagation of tau may become a treatment strategy in TBI.

=====WOW AMAZING...TSS=====

WEDNESDAY, JUNE 14, 2017

Amyloid-β accumulation in human growth hormone related iatrogenic CJD patients in the UK

http://betaamyloidcjd.blogspot.com/2017/06/amyloid-accumulation-in-human-growth.html

Saturday, June 17, 2017

PRION 2017 P115 α- Synuclein prions from MSA patients exhibit similar transmission properties as PrPSc prions

http://msaprion.blogspot.com/2017/06/prion-2017-p115-synuclein-prions-from.html

Thursday, July 6, 2017

PRION 2017 CONFERENCE ABSTRACTS HUMAN TSE PRION DISEASE

http://prionprp.blogspot.com/2017/07/prion-2017-conference-abstracts-human.html

TUESDAY, JUNE 20, 2017

Prion 2017 Conference Transmissible prions in the skin of Creutzfeldt-Jakob disease patients

http://creutzfeldt-jakob-disease.blogspot.com/2017/06/prion-2017-conference-transmissible.html

WEDNESDAY, MAY 03, 2017

*** First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques

http://chronic-wasting-disease.blogspot.com/2017/05/first-evidence-of-intracranial-and.html

FRIDAY, JUNE 16, 2017

PRION 2017 P55 Susceptibility of human prion protein to in vitro conversion by chronic wasting disease prions

http://chronic-wasting-disease.blogspot.com/2017/06/p55-susceptibility-of-human-prion.html

MONDAY, JUNE 19, 2017

PRION 2017 P20 Descriptive epidemiology of human prion diseases in Japan: a prospective 16-year surveillance study

Japan Prion Disease Increasing Annually to 2.3 patients per 1 million populations in 2014

http://creutzfeldt-jakob-disease.blogspot.com/2017/06/prion-2017-p20-descriptive-epidemiology.html

TUESDAY, JUNE 13, 2017

PRION 2017 CONFERENCE ABSTRACT Chronic Wasting Disease in European moose is associated with PrPSc features different from North American CWD

http://chronic-wasting-disease.blogspot.com/2017/06/prion-2017-conference-abstract-chronic.html

SATURDAY, JUNE 10, 2017

Chronic Wasting Disease CWD TSE Prion to Humans, who makes that final call, when, or, has it already happened?

http://chronic-wasting-disease.blogspot.com/2017/06/chronic-wasting-disease-cwd-tse-prion_10.html

MONDAY, JUNE 19, 2017

PRION 2017 CONFERENCE ABSTRACT P61 vCJD strain properties in a Spanish mother and son replicate as those of a young UK case


TUESDAY, JULY 04, 2017

PRION 2017 CONFERENCE ABSTRACTS ON CHRONIC WASTING DISEASE CWD TSE PRION


Subject: PRION 2017 CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS VIDEO

PRION 2017 CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS

PRION 2017 CONFERENCE VIDEO



Thursday, June 29, 2017

PRION 2017 CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS VIDEO


Wednesday, May 24, 2017

PRION2017 CONFERENCE VIDEO UPDATE 23 – 26 May 2017 Edinburgh UPDATE 1

Subject: PRION2017 CONFERENCE VIDEO UPDATE 23 – 26 May 2017 Edinburgh

*see archives of previous Prion Conferences, the ones that are still available, scroll down towards bottom in this link.



THURSDAY, JUNE 22, 2017

National Prion Disease Pathology Surveillance Center Cases Examined(1) (May 18, 2017)





















Terry S. Singeltary Sr.
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Wednesday, June 7, 2017

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

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.
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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 ;
Terry S. Singeltary Sr.
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Tuesday, December 6, 2016

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

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

  1. Stanley B. Prusinera,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
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    3. Authors & Info
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    5. SI
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    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.

    Footnotes

    • 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
     
     
    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.




    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


    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



    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

     
     
     
    Tuesday, November 29, 2016
     
    Transmissibility of Gerstmann–Sträussler–Scheinker syndrome in rodent models: new insights into the molecular underpinnings of prion infectivity
     
     

    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



     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



     *** 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


    Tuesday, November 29, 2016
     
    Transmissibility of Gerstmann–Sträussler–Scheinker syndrome in rodent models: new insights into the molecular underpinnings of prion infectivity
     


     
    Terry S. Singeltary Sr.
    Bacliff, Texas USA 77518


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