NIH Study Suggests That Early Detection is Possible for Prion Diseases
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NIH Study Suggests That Early Detection is Possible for Prion Diseases
A fast test to diagnose fatal brain conditions such as mad cow disease in cattle and Creutzfeldt-Jakob disease in humans could be on the horizon, according to a new study from National Institutes of Health scientists. Researchers at NIH’s National Institute of Allergy and Infectious Diseases (NIAID) have developed a highly sensitive and rapid new method to detect and measure infectious agents called prions that cause these diseases.
“Although relatively rare in humans and other animals, prion diseases are devastating to those infected and can have huge economic impacts,” says Anthony S. Fauci, M.D., director of NIAID. “Scientists have promising concepts for developing therapies for people infected with prion diseases, but treatments only are helpful if it is known who needs them. This detection model could eventually bridge that gap.”
This image, magnified 100,000 times using a transmission electron microscope, shows thread-like structures of prion protein. View larger image Credit: NIAID/RML Prion diseases are primarily brain-damaging conditions also known as transmissible spongiform encephalopathies. They are difficult to diagnose, untreatable and ultimately fatal. A key physical characteristic of these diseases is dead tissue that leaves sponge-like holes in the brain. Prion diseases include mad cow disease, or bovine spongiform encephalopathy in cattle; scrapie in sheep; Creutzfeldt-Jakob disease in humans; and chronic wasting disease in deer, elk and moose. For more information about NIAID research on prion diseases, visit the NIAID Prion Diseases portal.
Currently available diagnostic tests lack the sensitivity, speed or quantitative capabilities required for many important applications in medicine, agriculture, wildlife biology and research. Because prion infections can be present for decades before disease symptoms appear, a better test might create the possibility for early treatment to stop the spread of disease and prevent death.
Now, a blending of previous test concepts by the NIAID group has led to the development of a new prion detection method, called real time quaking induced conversion assay, or RT-QuIC. This approach is described in a paper now online in the open-access journal PLoS Pathogens. Byron Caughey, Ph.D., led the study at NIAID’s Rocky Mountain Laboratories in Hamilton, Mont.
Scientists believe disease-causing prions are abnormal infectious clusters of prion protein molecules. Normally, prion protein molecules are unclustered, harmless and found in every mammal. In a process not fully understood, abnormal infectious clusters develop and can convert normal prion protein molecules into the infectious prion form; these clusters tend to gather in the brain. Ongoing replication allows the disease to spread and damage the brain.
Infectious prions also are found outside the brain, in saliva, blood, breast milk, urine and the nasal and cerebral spinal fluids used in the study. But the concentrations of infectious prions in these bodily fluids are so low that scientists, clinicians and wildlife biologists have not been able to measure them for routine purposes.
The new assay can detect when miniscule amounts of infectious prions initiate the conversion of large amounts of normal prion protein into an abnormal form in test-tube reactions. By comparing the extent to which different samples can be diluted and still initiate conversion, scientists can estimate the relative infectious concentrations in the original samples. In their study, the NIAID scientists used RT-QuIC to detect prion infections in deer known to have chronic wasting disease and sheep known to have scrapie. In scrapie-infected hamsters, they found surprisingly high levels of prions in nasal fluids, pointing to such fluids as possible sources of contagion in various prion diseases.
Along with optimizing their existing applications in the laboratory, Dr. Caughey and his colleagues are teaming up with a number of other laboratories around the world to extend the practical and scientific applications of RT-QuIC. Related testing approaches might also aid the diagnoses of similar neurodegenerative protein diseases, such as Alzheimer’s, Huntington’s and Parkinson’s diseases. NIAID conducts and supports research—at NIH, throughout the United States, and worldwide—to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
The National Institutes of Health (NIH)—The Nation's Medical Research Agency—includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
Reference: J Wilham et al. Rapid end-point quantitation of prion seeding activity with sensitivity comparable to bioassays. PLoS Pathogens 6(12): e1001217. DOI: 10.1371/journal.ppat.1001217 (2010).
NIAID conducts and supports research—at NIH, throughout the United States, and worldwide—to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at www.niaid.nih.gov.
The National Institutes of Health (NIH)—The Nation's Medical Research Agency—includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
Rapid End-Point Quantitation of Prion Seeding Activity with Sensitivity Comparable to Bioassays Prion diseases are deadly infectious neurodegenerative disorders of mammals which involve the misfolding of host prion protein. To better manage these diseases, we need to be able to detect and quantify the infectious particles, or prions, in biological samples. However, current tests lack the sensitivity, speed and/or quantitative capabilities required for many important applications in medicine, agriculture, wildlife biology and research. To address this problem, we have developed a new prion assay that is highly sensitive, rapid, and quantitative. This assay takes advantage of the ability of miniscule amounts of infectious prions to seed the misfolding of large excesses of normal prion protein in test tube reactions. Quantitation is achieved by testing a range of sample dilutions and determining loss of seeding activity, i.e. the end-point dilution. Similar analyses have long been used to quantify prions by inoculation into animals; however, such bioassays take months or years to perform and are both animal-intensive and expensive. Our new method provides a more practical means of detecting and quantifying prions. So far, we have applied this assay to prions from sheep, deer, and hamsters, and have found surprisingly high levels of prions in the nasal and cerebral spinal fluids of infected hamsters.
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Abstract Author Summary Introduction Materials and Methods Results Discussion Supporting Information Acknowledgments Author Contributions References Jason M. Wilham1, Christina D. Orrú1,2, Richard A. Bessen3, Ryuichiro Atarashi4, Kazunori Sano4, Brent Race1, Kimberly D. Meade-White1, Lara M. Taubner1, Andrew Timmes1, Byron Caughey1*
1 Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, Hamilton, Montana, United States of America, 2 Department of Biomedical Sciences and Technologies, University of Cagliari, Monserrato, Italy, 3 Veterinary Molecular Biology, Montana State University, Bozeman, Montana, United States of America, 4 Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Kyushu, Japan
Abstract Top A major problem for the effective diagnosis and management of prion diseases is the lack of rapid high-throughput assays to measure low levels of prions. Such measurements have typically required prolonged bioassays in animals. Highly sensitive, but generally non-quantitative, prion detection methods have been developed based on prions' ability to seed the conversion of normally soluble protease-sensitive forms of prion protein to protease-resistant and/or amyloid fibrillar forms. Here we describe an approach for estimating the relative amount of prions using a new prion seeding assay called real-time quaking induced conversion assay (RT-QuIC). The underlying reaction blends aspects of the previously described quaking-induced conversion (QuIC) and amyloid seeding assay (ASA) methods and involves prion-seeded conversion of the alpha helix-rich form of bacterially expressed recombinant PrPC to a beta sheet-rich amyloid fibrillar form. The RT-QuIC is as sensitive as the animal bioassay, but can be accomplished in 2 days or less. Analogous to end-point dilution animal bioassays, this approach involves testing of serial dilutions of samples and statistically estimating the seeding dose (SD) giving positive responses in 50% of replicate reactions (SD50). Brain tissue from 263K scrapie-affected hamsters gave SD50 values of 1011-1012/g, making the RT-QuIC similar in sensitivity to end-point dilution bioassays. Analysis of bioassay-positive nasal lavages from hamsters affected with transmissible mink encephalopathy gave SD50 values of 103.5–105.7/ml, showing that nasal cavities release substantial prion infectivity that can be rapidly detected. Cerebral spinal fluid from 263K scrapie-affected hamsters contained prion SD50 values of 102.0–102.9/ml. RT-QuIC assay also discriminated deer chronic wasting disease and sheep scrapie brain samples from normal control samples. In principle, end-point dilution quantitation can be applied to many types of prion and amyloid seeding assays. End point dilution RT-QuIC provides a sensitive, rapid, quantitative, and high throughput assay of prion seeding activity.
Author Summary Top Prion diseases are deadly infectious neurodegenerative disorders of mammals which involve the misfolding of host prion protein. To better manage these diseases, we need to be able to detect and quantify the infectious particles, or prions, in biological samples. However, current tests lack the sensitivity, speed and/or quantitative capabilities required for many important applications in medicine, agriculture, wildlife biology and research. To address this problem, we have developed a new prion assay that is highly sensitive, rapid, and quantitative. This assay takes advantage of the ability of miniscule amounts of infectious prions to seed the misfolding of large excesses of normal prion protein in test tube reactions. Quantitation is achieved by testing a range of sample dilutions and determining loss of seeding activity, i.e. the end-point dilution. Similar analyses have long been used to quantify prions by inoculation into animals; however, such bioassays take months or years to perform and are both animal-intensive and expensive. Our new method provides a more practical means of detecting and quantifying prions. So far, we have applied this assay to prions from sheep, deer, and hamsters, and have found surprisingly high levels of prions in the nasal and cerebral spinal fluids of infected hamsters.
Citation: Wilham JM, Orrú CD, Bessen RA, Atarashi R, Sano K, et al. (2010) Rapid End-Point Quantitation of Prion Seeding Activity with Sensitivity Comparable to Bioassays. PLoS Pathog 6(12): e1001217. doi:10.1371/journal.ppat.1001217
Editor: David Westaway, University of Alberta, Canada
Received: May 4, 2010; Accepted: November 3, 2010; Published: December 2, 2010
This is an open-access article distributed under the terms of the Creative Commons Public Domain declaration which stipulates that, once placed in the public domain, this work may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose.
Funding: This research was funded by the Intramural Research Program of the NIAID, NIH. J.M.W. was supported in part by the Undergraduate Scholarship Program of the NIH and C.D.O. was partially supported by the Master and Back Program of the Regione Sardegna (Italy). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
* E-mail: BCAUGHEY@niaid.nih.gov
SNIP...SEE FULL TEXT ;
ONE has to want to find a TSE in order to really find it. I have NOT seen this with the USDA and CDC et al in relations to human and animal TSE i.e. the USA bovine, or any other animal TSE here in North America and and human CJD there from, and all human TSE, not just the 55 and younger. where is it wrote in stone that only the young can only have a CJD related to other species TSE and or iCJD there from, and all the rest, the 55 and older, it is all a happenstance of bad luck, a spontaneous mutation from nothing, a protein that twisted the wrong way, and which by the way is running now at or about 1 in 9,000 in 55 and older, so please, forget this one in a million BSe $$$ i agree with Collinge al recently and have been saying for a long time ;
"These results demonstrate the existence of subclinical forms of prion infection with important public health implications, both with respect to iatrogenic transmission from apparently healthy humans and dietary exposure to cattle and other species exposed to bovine spongiform encephalopathy prions, Current definitions of the species barrier, which have been based on clinical endpoints, need to be fundamentally reassessed."
and for the following reasons, i see little hope for any mass testing of any species for TSE in the USA in the near future, so the good news is in itself good news, it really means nothing in my opinion for the consumer here in the USA. ...TSS
Thursday, November 18, 2010
UNITED STATES OF AMERICA VS GALEN J. NIEHUES FAKED MAD COW FEED TEST ON 92 BSE INSPECTION REPORTS FOR APPROXIMATELY 100 CATTLE OPERATIONS
Wednesday, November 17, 2010
MAD COW TESTING FAKED IN USA BY Nebraska INSPECTOR Senator Mike Johanns STATE
Saturday, November 6, 2010
TAFS1 Position Paper on Position Paper on Relaxation of the Feed Ban in the EU Berne, 2010 TAFS
INTERNATIONAL FORUM FOR TRANSMISSIBLE ANIMAL DISEASES AND FOOD SAFETY a non-profit Swiss Foundation
Detwiler, a former official with USDA’s Animal and Plant Health Inspection Service, said the origin of "atypical" BSE is unknown at this stage. Speculation has focused on whether it is a variation or mutation of classical BSE, or whether it is caused by a different route of exposure, or exposure of the animal at an older age. There is no definitive evidence that "atypical" BSE occurs sporadically, she said. But scientists have shown that tissues – such as brain and spinal cord – infected with "atypical" BSE are infectious. Based upon what currently is known, she advised that cattle surveillance be maintained, and said it may be necessary to "rethink" the target population of animals tested for BSE to include more apparently healthy older cattle. She also said additional
research is needed on the pathogenesis of "atypical" BSE and how it may be transmitted to cattle or other species; and she encouraged countries not to relax BSE-prevention feed restrictions.
October 27, 2006...END...TSS
10,000,000+ LBS. of PROHIBITED BANNED MAD COW FEED I.E. BLOOD LACED MBM IN COMMERCE USA 2007
Date: March 21, 2007 at 2:27 pm PST
RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINES -- CLASS II
Bulk cattle feed made with recalled Darling's 85% Blood Meal, Flash Dried, Recall # V-024-2007
Cattle feed delivered between 01/12/2007 and 01/26/2007
Pfeiffer, Arno, Inc, Greenbush, WI. by conversation on February 5, 2007.
Firm initiated recall is ongoing.
Blood meal used to make cattle feed was recalled because it was cross- contaminated with prohibited bovine meat and bone meal that had been manufactured on common equipment and labeling did not bear cautionary BSE statement.
VOLUME OF PRODUCT IN COMMERCE
Custom dairy premix products: MNM ALL PURPOSE Pellet, HILLSIDE/CDL Prot- Buffer Meal, LEE, M.-CLOSE UP PX Pellet, HIGH DESERT/ GHC LACT Meal, TATARKA, M CUST PROT Meal, SUNRIDGE/CDL PROTEIN Blend, LOURENZO, K PVM DAIRY Meal, DOUBLE B DAIRY/GHC LAC Mineral, WEST PIONT/GHC CLOSEUP Mineral, WEST POINT/GHC LACT Meal, JENKS, J/COMPASS PROTEIN Meal, COPPINI - 8# SPECIAL DAIRY Mix, GULICK, L-LACT Meal (Bulk), TRIPLE J - PROTEIN/LACTATION, ROCK CREEK/GHC MILK Mineral, BETTENCOURT/GHC S.SIDE MK-MN, BETTENCOURT #1/GHC MILK MINR, V&C DAIRY/GHC LACT Meal, VEENSTRA, F/GHC LACT Meal, SMUTNY, A- BYPASS ML W/SMARTA, Recall # V-025-2007
The firm does not utilize a code - only shipping documentation with commodity and weights identified.
Rangen, Inc, Buhl, ID, by letters on February 13 and 14, 2007. Firm initiated recall is complete.
Products manufactured from bulk feed containing blood meal that was cross contaminated with prohibited meat and bone meal and the labeling did not bear cautionary BSE statement.
VOLUME OF PRODUCT IN COMMERCE
ID and NV
END OF ENFORCEMENT REPORT FOR MARCH 21, 2007
Saturday, August 14, 2010
BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY
(see mad cow feed in COMMERCE IN ALABAMA...TSS)
Wednesday, July 28, 2010
re-Freedom of Information Act Project Number 3625-32000-086-05, Study of Atypical BSE UPDATE July 28, 2010
Wednesday, July 28, 2010
Atypical prion proteins and IBNC in cattle DEFRA project code SE1796 FOIA Final report
Monday, August 9, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the prion protein or just more Prionbaloney ?
Archive Number 20101206.4364 Published Date 06-DEC-2010 Subject PRO/AH/EDR> Prion disease update 2010 (11)
PRION DISEASE UPDATE 2010 (11)
Saturday, December 11, 2010
Species-barrier-independent prion replication in apparently resistant species
Sunday, December 12, 2010
Predominant Involvement of the Cerebellum in Guinea Pigs Infected with Bovine Spongiform Encephalopathy (BSE)
Journal of Comparative Pathology Article in Press
Monday, November 22, 2010
Atypical transmissible spongiform encephalopathies in ruminants: a challenge for disease surveillance and control
Saturday, June 13, 2009
Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States 2003 revisited 2009
Manuscript Draft Manuscript Number: Title: HUMAN and ANIMAL TSE Classifications i.e. mad cow disease and the UKBSEnvCJD only theory Article Type: Personal View Corresponding Author: Mr. Terry S. Singeltary, Corresponding Author's Institution: na First Author: Terry S Singeltary, none Order of Authors: Terry S Singeltary, none; Terry S. Singeltary
Abstract: TSEs have been rampant in the USA for decades in many species, and they all have been rendered and fed back to animals for human/animal consumption. I propose that the current diagnostic criteria for human TSEs only enhances and helps the spreading of human TSE from the continued belief of the UKBSEnvCJD only theory in 2007.
Saturday, January 2, 2010
Human Prion Diseases in the United States January 1, 2010 ***FINAL***
my comments to PLosone here ;
Meeting of the Transmissible Spongiform Encephalopathies Committee On June 12, 2009 (Singeltary submission)
Monday, August 9, 2010
National Prion Disease Pathology Surveillance Center Cases Examined (July 31, 2010)
Sunday, November 28, 2010
Variably protease-sensitive prionopathy in a PRNP codon 129 heterozygous UK patient with co-existing tau, a synuclein and AB pathology
HOW many of you recieved a written CJD Questionnaire asking real questions pertaining to route and source (and there are many here in North America) ?
IS every case getting a cjd questionnaire asking real questions ???
Friday, November 30, 2007
CJD QUESTIONNAIRE USA CWRU AND CJD FOUNDATION USA PRION UNIT