DNR removes deer carcasses, admits error
Eric Atherton, eatherton@postbulletin.com Updated 1 hr ago (1)
Eric Atherton
Bones are about all that remain of several dozen deer carcasses that were piled earlier this week not far from a trail through the wildlife management area near Quarry Hill Nature Center. The Minnesota DNR removed the carcasses after a video of the dead deer was posted online.
The "discovery" of a site where the Minnesota Department of Natural Resources has been dumping deer carcasses for years has prompted a public outcry — and an admission from the DNR that in this case its protocols were not being followed.
The site came to light in late December when a pheasant hunter found a pile of dead deer on the Gordon Yeager Wildlife Management Area north of Rochester Community and Technical College and south of Quarry Hill Nature Center. He shot a video that showed several dozen deer carcasses and severed heads, and that video was posted to the Minnesota Hunting Club's Facebook page, where it has been shared more than 11,000 times.
Lt. Tyler Quandt, supervisor of the DNR District 18 Enforcement District, said the carcasses were removed Wednesday. He also explained how they came to be there in the first place. "These were deer that were shot illegally and were seized by law enforcement, or people called in a complaint about discovering a dead deer somewhere," he said.
Ideally, confiscated deer are given to families who need the meat, but sometimes the animals have spoiled and cannot be salvaged. In such cases, Quandt said it's standard practice for the DNR to dump the carcasses on public lands.
"This type of thing has been going on since the DNR has been around," he said. "We've had game wardens in our state for 120 years, and for 120 years we've taken deer that can't be salvaged and we dump them in specific places on public lands." In this case, however, the deer were dumped was less than 150 yards from a parking area and just a few feet off of a mowed trail that, in recent years, has begun to get more traffic.
"The city of Rochester is developing in every direction, and there's getting to be more businesses and houses in that area," Quandt said. "People are walking dogs or just going for walks in that area, so that kind of activity has increased."
Other than the unsightly aspect of the dump site so near a public trail, the DNR now admits that at least one other mistake was made at this dump site. Chris Niskanen, communications director for the DNR, said some deer heads found at the site were supposed to have a different final destination.
"The deer heads at the site were from hunter-harvested deer that were tested for chronic wasting disease as part of the DNR's surveillance program," he said. "All the heads tested negative. Unfortunately, agency protocol for disposing of the heads in the landfill was not followed in all cases, and some heads were left at the disposal site."
Chronic wasting disease is an always-fatal neurological disease that affects deer, elk and moose. It's a hot topic in southeastern Minnesota right now after three deer tested positive for CWD in the Preston area. A special hunt is now underway to curb the spread of the disease and determine how many deer are infected.
The dump site at Gordon Yeager WMA will no longer be used, but Niskanen said the DNR will continue to dispose of animal carcasses on public lands across the state.
"We are responsible under state statute to manage wildlife (dead or alive) on state lands and WMAs, and we find it necessary to use discreet and remote areas to allow confiscated deer carcasses that are unfit for human consumption to decompose naturally," he said. "It saves on landfill space and the cost of disposal. Still, we acknowledge the unfortunate circumstances of this situation and we are making corrections. We are also reviewing other sites to ensure they are remote and not visible to the public."
Among the complaints that hunters have been voicing on social media is the fact that people who butcher the deer they shoot are prohibited from dumping the carcasses on public land.
Is that a double standard?
Not at all, Quandt said.
"We are the state of Minnesota, acting on behalf of the state of Minnesota, disposing of deer carcasses on land controlled by the state," he said. "And there's no law against disposing of deer on private land. If I get permission from Farmer Joe to hunt deer on his property, he can also give me permission to dump the remains on his land after I butcher a deer."
Quandt added that letting a deer decompose naturally is far better than burying it in a landfill. "Between the crows, coyotes, skunks, foxes and other critters, the animal doesn't go to waste," he said. "It is utilized by nature, and we believe that is the best way for them to be disposed of."
HOLY MAD COW BATMAN, just when I thought the mad cow debacle could not get any more stupid, dumb and dumber step up to the plate. please let me explain...
The "discovery" of a site where the Minnesota Department of Natural Resources has been dumping deer carcasses for years has prompted a public outcry — and an admission from the DNR that in this case its protocols were not being followed.
Lt. Tyler Quandt, supervisor of the DNR District 18 Enforcement District stated ;
''Quandt added that letting a deer decompose naturally is far better than burying it in a landfill. "Between the crows, coyotes, skunks, foxes and other critters, the animal doesn't go to waste," he said. "It is utilized by nature, and we believe that is the best way for them to be disposed of."
"This type of thing has been going on since the DNR has been around," he said. "We've had game wardens in our state for 120 years, and for 120 years we've taken deer that can't be salvaged and we dump them in specific places on public lands."
I suggest Lt. Tyler Quandt et al study this very closely, AND THEN MAYBE CHANGE THEIR STUPID POLICY IMO.
stupid is, as stupid does, and some times you just can't fix stupid, and this was/is a colossal debacle.
Inactivation of the TSE Prion disease
Chronic Wasting Disease CWD, and other TSE prion disease, these TSE prions know no borders.
these TSE prions know no age restrictions.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with. that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.
stupid is, as stupid does, and some times you just can't fix stupid, and this was/is a colossal debacle.
Inactivation of the TSE Prion disease
Chronic Wasting Disease CWD, and other TSE prion disease, these TSE prions know no borders.
these TSE prions know no age restrictions.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with. that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.
Chronic Wasting Disease (CWD) Susceptibility of Several North American Rodents That Are Sympatric with Cervid CWD Epidemics▿
Chronic Wasting Disease Susceptibility of Four North American Rodents
Chad J. Johnson1*, Jay R. Schneider2, Christopher J. Johnson2, Natalie A. Mickelsen2, Julia A. Langenberg3, Philip N. Bochsler4, Delwyn P. Keane4, Daniel J. Barr4, and Dennis M. Heisey2 1University of Wisconsin School of Veterinary Medicine, Department of Comparative Biosciences, 1656 Linden Drive, Madison WI 53706, USA 2US Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison WI 53711, USA 3Wisconsin Department of Natural Resources, 101 South Webster Street, Madison WI 53703, USA 4Wisconsin Veterinary Diagnostic Lab, 445 Easterday Lane, Madison WI 53706, USA *Corresponding author email: cjohnson@svm.vetmed.wisc.edu
We intracerebrally challenged four species of native North American rodents that inhabit locations undergoing cervid chronic wasting disease (CWD) epidemics. The species were: deer mice (Peromyscus maniculatus), white-footed mice (P. leucopus), meadow voles (Microtus pennsylvanicus), and red-backed voles (Myodes gapperi). The inocula were prepared from the brains of hunter-harvested white-tailed deer from Wisconsin that tested positive for CWD. Meadow voles proved to be most susceptible, with a median incubation period of 272 days. Immunoblotting and immunohistochemistry confirmed the presence of PrPd in the brains of all challenged meadow voles. Subsequent passages in meadow voles lead to a significant reduction in incubation period. The disease progression in red-backed voles, which are very closely related to the European bank vole (M. glareolus) which have been demonstrated to be sensitive to a number of TSEs, was slower than in meadow voles with a median incubation period of 351 days. We sequenced the meadow vole and red-backed vole Prnp genes and found three amino acid (AA) differences outside of the signal and GPI anchor sequences. Of these differences (T56-, G90S, S170N; read-backed vole:meadow vole), S170N is particularly intriguing due its postulated involvement in "rigid loop" structure and CWD susceptibility. Deer mice did not exhibit disease signs until nearly 1.5 years post-inoculation, but appear to be exhibiting a high degree of disease penetrance. White-footed mice have an even longer incubation period but are also showing high penetrance. Second passage experiments show significant shortening of incubation periods. Meadow voles in particular appear to be interesting lab models for CWD. These rodents scavenge carrion, and are an important food source for many predator species. Furthermore, these rodents enter human and domestic livestock food chains by accidental inclusion in grain and forage. Further investigation of these species as potential hosts, bridge species, and reservoirs of CWD is required.
Veterinary Pathology Onlinevet.sagepub.com Published online before print February 27, 2014, doi: 10.1177/0300985814524798 Veterinary Pathology February 27, 2014 0300985814524798
Lesion Profiling and Subcellular Prion Localization of Cervid Chronic Wasting Disease in Domestic Cats
D. M. Seelig1⇑ A. V. Nalls1 M. Flasik2 V. Frank1 S. Eaton2 C. K. Mathiason1 E. A. Hoover1 1Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA 2Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA D. M. Seelig, University of Minnesota, Department of Veterinary Clinical Sciences, Room 339 VetMedCtrS, 6192A (Campus Delivery Code), 1352 Boyd Ave, St Paul, MN 55108, USA. Email address: dseelig@umn.edu
Abstract
Chronic wasting disease (CWD) is an efficiently transmitted, fatal, and progressive prion disease of cervids with an as yet to be fully clarified host range. While outbred domestic cats (Felis catus) have recently been shown to be susceptible to experimental CWD infection, the neuropathologic features of the infection are lacking. Such information is vital to provide diagnostic power in the event of natural interspecies transmission and insights into host and strain interactions in interspecies prion infection. Using light microscopy and immunohistochemistry, we detail the topographic pattern of neural spongiosis (the “lesion profile”) and the distribution of misfolded prion protein in the primary and secondary passage of feline CWD (FelCWD). We also evaluated cellular and subcellular associations between misfolded prion protein (PrPD) and central nervous system neurons and glial cell populations. From these studies, we (1) describe the novel neuropathologic profile of FelCWD, which is distinct from either cervid CWD or feline spongiform encephalopathy (FSE), and (2) provide evidence of serial passage-associated interspecies prion adaptation. In addition, we demonstrate through confocal analysis the successful co-localization of PrPD with neurons, astrocytes, microglia, lysosomes, and synaptophysin, which, in part, implicates each of these in the neuropathology of FelCWD. In conclusion, this work illustrates the simultaneous role of both host and strain in the development of a unique FelCWD neuropathologic profile and that such a profile can be used to discriminate between FelCWD and FSE.
prion chronic wasting disease immunohistochemistry interspecies cat feline spongiform encephalopathy transmissible spongiform encephalopathy adaptation species barrier
Monday, August 8, 2011 Susceptibility of Domestic Cats to CWD Infection
Oral.29: Susceptibility of Domestic Cats to CWD Infection
Amy Nalls, Nicholas J. Haley, Jeanette Hayes-Klug, Kelly Anderson, Davis M. Seelig, Dan S. Bucy, Susan L. Kraft, Edward A. Hoover and Candace K. Mathiason†
Colorado State University; Fort Collins, CO USA†Presenting author; Email: ckm@lamar.colostate.edu
Domestic and non-domestic cats have been shown to be susceptible to one prion disease, feline spongiform encephalopathy (FSE), thought to be transmitted through consumption of bovine spongiform encephalopathy (BSE) contaminated meat. Because domestic and free ranging felids scavenge cervid carcasses, including those in CWD affected areas, we evaluated the susceptibility of domestic cats to CWD infection experimentally. Groups of n = 5 cats each were inoculated either intracerebrally (IC) or orally (PO) with CWD deer brain homogenate. Between 40–43 months following IC inoculation, two cats developed mild but progressive symptoms including weight loss, anorexia, polydipsia, patterned motor behaviors and ataxia—ultimately mandating euthanasia. Magnetic resonance imaging (MRI) on the brain of one of these animals (vs. two age-matched controls) performed just before euthanasia revealed increased ventricular system volume, more prominent sulci, and T2 hyperintensity deep in the white matter of the frontal hemisphere and in cortical grey distributed through the brain, likely representing inflammation or gliosis. PrPRES and widely distributed peri-neuronal vacuoles were demonstrated in the brains of both animals by immunodetection assays. No clinical signs of TSE have been detected in the remaining primary passage cats after 80 months pi. Feline-adapted CWD was sub-passaged into groups (n=4 or 5) of cats by IC, PO, and IP/SQ routes. Currently, at 22 months pi, all five IC inoculated cats are demonstrating abnormal behavior including increasing aggressiveness, pacing, and hyper responsiveness.
*** Two of these cats have developed rear limb ataxia. Although the limited data from this ongoing study must be considered preliminary, they raise the potential for cervid-to-feline transmission in nature.
AD.63:
Susceptibility of domestic cats to chronic wasting disease
Amy V.Nalls,1 Candace Mathiason,1 Davis Seelig,2 Susan Kraft,1 Kevin Carnes,1 Kelly Anderson,1 Jeanette Hayes-Klug1 and Edward A. Hoover1 1Colorado State University; Fort Collins, CO USA; 2University of Minnesota; Saint Paul, MN USA
Domestic and nondomestic cats have been shown to be susceptible to feline spongiform encephalopathy (FSE), almost certainly caused by consumption of bovine spongiform encephalopathy (BSE)-contaminated meat. Because domestic and free-ranging nondomestic felids scavenge cervid carcasses, including those in areas affected by chronic wasting disease (CWD), we evaluated the susceptibility of the domestic cat (Felis catus) to CWD infection experimentally. Cohorts of 5 cats each were inoculated either intracerebrally (IC) or orally (PO) with CWD-infected deer brain. At 40 and 42 mo post-inoculation, two IC-inoculated cats developed signs consistent with prion disease, including a stilted gait, weight loss, anorexia, polydipsia, patterned motor behaviors, head and tail tremors, and ataxia, and progressed to terminal disease within 5 mo. Brains from these two cats were pooled and inoculated into cohorts of cats by IC, PO, and intraperitoneal and subcutaneous (IP/SC) routes. Upon subpassage, feline-adapted CWD (FelCWD) was transmitted to all IC-inoculated cats with a decreased incubation period of 23 to 27 mo. FelCWD was detected in the brains of all the symptomatic cats by western blotting and immunohistochemistry and abnormalities were seen in magnetic resonance imaging, including multifocal T2 fluid attenuated inversion recovery (FLAIR) signal hyper-intensities, ventricular size increases, prominent sulci, and white matter tract cavitation. Currently, 3 of 4 IP/SQ and 2 of 4 PO inoculared cats have developed abnormal behavior patterns consistent with the early stage of feline CWD.
*** These results demonstrate that CWD can be transmitted and adapted to the domestic cat, thus raising the issue of potential cervid-to- feline transmission in nature.
www.landesbioscience.com
see much more science on cwd and feline transmission here ;
Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay
Christopher J. Johnson1, Christina M. Carlson2, Aaron R. Morawski3, Alyson Manthei4, Neil R. Cashman5
1USGS National Wildlife Health Center, 2Department of Soil Science, University of Wisconsin–Madison, 3Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4Merial Veterinary Scholars Program, School of Veterinary Medicine, University of Wisconsin–Madison, 5Department of Neurology, University of British Columbia
Summary
Measuring the barrier to the interspecies transmission of prion diseases is challenging and typically involves animal challenges or biochemical assays. Here, we present an in vitro prion protein conversion assay with the ability to predict species barriers.
Date Published: 3/10/2015, Issue 97; doi: 10.3791/52522
Keywords: Medicine, Issue 97, Prion, species barrier, conversion, immunoblotting, transmissible spongiform encephalopathy, interspecies transmission Cite this Article
Johnson, C. J., Carlson, C. M., Morawski, A. R., Manthei, A., Cashman, N. R. Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay. J. Vis. Exp. (97), e52522, doi:10.3791/52522 (2015). Abstract
Studies to understanding interspecies transmission of transmissible spongiform encephalopathies (TSEs, prion diseases) are challenging in that they typically rely upon lengthy and costly in vivo animal challenge studies. A number of in vitro assays have been developed to aid in measuring prion species barriers, thereby reducing animal use and providing quicker results than animal bioassays. Here, we present the protocol for a rapid in vitro prion conversion assay called the conversion efficiency ratio (CER) assay. In this assay cellular prion protein (PrPC) from an uninfected host brain is denatured at both pH 7.4 and 3.5 to produce two substrates. When the pH 7.4 substrate is incubated with TSE agent, the amount of PrPC that converts to a proteinase K (PK)-resistant state is modulated by the original host’s species barrier to the TSE agent. In contrast, PrPC in the pH 3.5 substrate is misfolded by any TSE agent. By comparing the amount of PK-resistant prion protein in the two substrates, an assessment of the host’s species barrier can be made. We show that the CER assay correctly predicts known prion species barriers of laboratory mice and, as an example, show some preliminary results suggesting that bobcats (Lynx rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting disease agent.
>>> show some preliminary results suggesting that bobcats (Lynx rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting disease agent.
PO-081: Chronic wasting disease in the cat— Similarities to feline spongiform encephalopathy (FSE)
FELINE SPONGIFORM ENCEPHALOPATHY FSE
Wednesday, October 17, 2012
Prion Remains Infectious after Passage through Digestive System of American Crows (Corvus brachyrhynchos)
HORIZONTAL TRANSMISSION OF THE CWD TSE PRION DISEASE AND ENVIRONMENTAL RISK FACTORS
*** Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission ***
PLEASE SEE DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE
Volume 22, Number 12—December 2016
Dispatch
Horizontal Transmission of Chronic Wasting Disease in Reindeer
Monday, September 05, 2016
Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission Major Findings for Norway
Thursday, September 22, 2016
NORWAY DETECTS 5TH CASE OF CHRONIC WASTING DISEASE CWD TSE PRION Skrantesjuke
SUNDAY, OCTOBER 02, 2016
*** What is the risk of a cervid TSE being introduced from Norway into Great Britain? Qualitative Risk Assessment September 2016
Sunday, December 11, 2016
Clay Components in Soil Dictate Environmental Stability and Bioavailability of Cervid Prions in Mice
Wednesday, December 14, 2016
Increased Abundance of M Cells in the Gut Epithelium Dramatically Enhances Oral Prion Disease Susceptibility
***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.
P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion
Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2
1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWO
In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible.
***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.
PRION 2016 CONFERENCE TOKYO
http://prion2016.org/dl/newsletter_03.pdf
P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion
Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2
1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWO
In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible.
***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.
PRION 2016 CONFERENCE TOKYO
http://prion2016.org/dl/newsletter_03.pdf
Saturday, May 28, 2016
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
http://chronic-wasting-disease.blogspot.com/2016/05/infection-and-detection-of-prpcwd-in.html
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
http://chronic-wasting-disease.blogspot.com/2016/05/infection-and-detection-of-prpcwd-in.html
*** Infectious agent of sheep scrapie may persist in the environment for at least 16 years ***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
Using in vitro prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission.
Claudio Soto
Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston.
Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.
=========================
***Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.
========================
Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis.
see ;
with CWD TSE Prions, I am not sure there is any absolute yet, other than what we know with transmission studies, and we know tse prion kill, and tse prion are bad. science shows to date, that indeed soil, dirt, some better than others, can act as a carrier. same with objects, farm furniture. take it with how ever many grains of salt you wish, or not. if load factor plays a role in the end formula, then everything should be on the table, in my opinion...tss
see ;
***Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.
Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis.
see ;
Oral Transmissibility of Prion Disease Is Enhanced by Binding to Soil Particles
Author Summary
Transmissible spongiform encephalopathies (TSEs) are a group of incurable neurological diseases likely caused by a misfolded form of the prion protein. TSEs include scrapie in sheep, bovine spongiform encephalopathy (‘‘mad cow’’ disease) in cattle, chronic wasting disease in deer and elk, and Creutzfeldt-Jakob disease in humans. Scrapie and chronic wasting disease are unique among TSEs because they can be transmitted between animals, and the disease agents appear to persist in environments previously inhabited by infected animals. Soil has been hypothesized to act as a reservoir of infectivity and to bind the infectious agent. In the current study, we orally dosed experimental animals with a common clay mineral, montmorillonite, or whole soils laden with infectious prions, and compared the transmissibility to unbound agent. We found that prions bound to montmorillonite and whole soils remained orally infectious, and, in most cases, increased the oral transmission of disease compared to the unbound agent. The results presented in this study suggest that soil may contribute to environmental spread of TSEs by increasing the transmissibility of small amounts of infectious agent in the environment.
https://www.aphis.usda.gov/emergency_response/downloads/tools/johnson%20et%20al%20prions%20in%20soil.pdf
tse prion soil
Wednesday, December 16, 2015
Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission
The sources of dust borne prions are unknown but it seems reasonable to assume that faecal, urine, skin, parturient material and saliva-derived prions may contribute to this mobile environmental reservoir of infectivity. This work highlights a possible transmission route for scrapie within the farm environment, and this is likely to be paralleled in CWD which shows strong similarities with scrapie in terms of prion dissemination and disease transmission. The data indicate that the presence of scrapie prions in dust is likely to make the control of these diseases a considerable challenge.
>>>Particle-associated PrPTSE molecules may migrate from locations of deposition via transport processes affecting soil particles, including entrainment in and movement with air and overland flow. <<<
Fate of Prions in Soil: A Review
Christen B. Smith, Clarissa J. Booth, and Joel A. Pedersen*
Several reports have shown that prions can persist in soil for several years. Significant interest remains in developing methods that could be applied to degrade PrPTSE in naturally contaminated soils. Preliminary research suggests that serine proteases and the microbial consortia in stimulated soils and compost may partially degrade PrPTSE. Transition metal oxides in soil (viz. manganese oxide) may also mediate prion inactivation. Overall, the effect of prion attachment to soil particles on its persistence in the environment is not well understood, and additional study is needed to determine its implications on the environmental transmission of scrapie and CWD.
P.161: Prion soil binding may explain efficient horizontal CWD transmission
Conclusion. Silty clay loam exhibits highly efficient prion binding, inferring a durable environmental reservoir, and an efficient mechanism for indirect horizontal CWD transmission.
>>>Another alternative would be an absolute prohibition on the movement of deer within the state for any purpose. While this alternative would significantly reduce the potential spread of CWD, it would also have the simultaneous effect of preventing landowners and land managers from implementing popular management strategies involving the movement of deer, and would deprive deer breeders of the ability to engage in the business of buying and selling breeder deer. Therefore, this alternative was rejected because the department determined that it placed an avoidable burden on the regulated community.<<<
Wednesday, December 16, 2015
Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission
Timm Konold1*, Stephen A. C. Hawkins2, Lisa C. Thurston3, Ben C. Maddison4, Kevin C. Gough5, Anthony Duarte1 and Hugh A. Simmons1
1 Animal Sciences Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK, 2 Pathology Department, Animal and Plant Health Agency Weybridge, Addlestone, UK, 3 Surveillance and Laboratory Services, Animal and Plant Health Agency Penrith, Penrith, UK, 4 ADAS UK, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK, 5 School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK
Classical scrapie is an environmentally transmissible prion disease of sheep and goats. Prions can persist and remain potentially infectious in the environment for many years and thus pose a risk of infecting animals after re-stocking. In vitro studies using serial protein misfolding cyclic amplification (sPMCA) have suggested that objects on a scrapie affected sheep farm could contribute to disease transmission. This in vivo study aimed to determine the role of field furniture (water troughs, feeding troughs, fencing, and other objects that sheep may rub against) used by a scrapie-infected sheep flock as a vector for disease transmission to scrapie-free lambs with the prion protein genotype VRQ/VRQ, which is associated with high susceptibility to classical scrapie. When the field furniture was placed in clean accommodation, sheep became infected when exposed to either a water trough (four out of five) or to objects used for rubbing (four out of seven). This field furniture had been used by the scrapie-infected flock 8 weeks earlier and had previously been shown to harbor scrapie prions by sPMCA. Sheep also became infected (20 out of 23) through exposure to contaminated field furniture placed within pasture not used by scrapie-infected sheep for 40 months, even though swabs from this furniture tested negative by PMCA. This infection rate decreased (1 out of 12) on the same paddock after replacement with clean field furniture. Twelve grazing sheep exposed to field furniture not in contact with scrapie-infected sheep for 18 months remained scrapie free. The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.
snip...
Discussion
Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20). Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22). Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23).
Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing. Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building. Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9). The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture. When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier.
This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep. Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease. It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled. Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases. Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA. Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions.
PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice. In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals. In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions). As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay. False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28). This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm. This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc. In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc. Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing. The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material. In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12). A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30). This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model. Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions.
In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination. These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes.
Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification
Wednesday, December 16, 2015
*** Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission ***
Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie Experiment 1964
How Did CWD Get Way Down In Medina County, Texas?
Confucius ponders...
Could the Scrapie experiments back around 1964 at Moore Air Force near Mission, Texas, could this area have been ground zero for CWD TSE Prion (besides the CWD cases that have waltzed across the Texas, New Mexico border near WSMR Trans Pecos region since around 2001)?
Epidemiology of Scrapie in the United States 1977
snip...
Scrapie Field Trial Experiments Mission, Texas
A Scrapie Field Trial was developed at Mission, Texas, to provide additional information for the eradication program on the epidemiology of natural scrapie. The Mission Field Trial Station is located on 450 acres of pastureland, part of the former Moore Air Force Base, near Mission, Texas. It was designed to bring previously exposed, and later also unexposed, sheep or goats to the Station and maintain and breed them under close observation for extended periods to determine which animals would develop scrapie and define more closely the natural spread and other epidemiological aspects of the disease.
The 547 previously exposed sheep brought to the Mission Station beginning in 1964 were of the Cheviot, Hampshire, Montadale, or Suffolk breeds. They were purchased as field outbreaks occurred, and represented 21 bloodlines in which scrapie had been diagnosed. Upon arrival at the Station, the sheep were maintained on pasture, with supplemental feeding as necessary. The station was divided into 2 areas: (1) a series of pastures and-pens occupied by male animals only, and (2) a series of pastures and pens occupied by females and young progeny of both sexes. ...
snip...see full text ;
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
Thursday, June 09, 2016
Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie TSE Prion Experiment 1964
How Did CWD Get Way Down In Medina County, Texas?
http://chronic-wasting-disease.blogspot.com/2016/06/how-did-cwd-get-way-down-in-medina.html
http://scrapie-usa.blogspot.com/2016/06/scrapie-field-trial-experiments-mission.html
Thursday, December 08, 2016
Prions
Walter Bodemer German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany Correspondence to: Walter Bodemer (wbodemer@dpz.eu)
Received: 15 June 2016 – Revised: 24 August 2016 – Accepted: 30 August 2016 – Published: 7 September 2016
Abstract.
Published by Copernicus Publications on behalf of the Deutsches Primatenzentrum GmbH (DPZ).
2.1 Animals The reason to perform prion research in rhesus monkeys was to monitor infection and the temporal progression of prion infection in the rhesus monkey. In contrast to studies of human CJD cases, we could decide on the infectious dose. We also could control behavior immediately after prion inoculation and during the rather long time until animals died from the prion infection. Hidden places where prions might exist were found. Even epigenetic modifications on RNA could be detected. Taken together, these experimental approaches depended on animals. Using rhesus monkeys as a model system required thorough ethic reasoning and consultation with authorities before we actually turned to conduct the experiments. The Number of animals was limited just to fulfill statistical conditions. The individual health status was obtained and health care was provided throughout the study. The animals underwent daily inspection to monitor any changes in health and behavior. The experiments were conceived with the aim of reducing pain, suffering, and harm. Groups of animals were preferred in order to keep them in a social environment. The animals were originally kept in Vienna at Baxter and transferred to the German Primate Center (DPZ) in 2001. J. Collinge, A. Aguzzi, and C. Weissmann were the scientists who recommended this well-controlled prion infection study, and financial support was provided by an EU grant.To ensure statistical significance four groups consisting of four rhesus macaques each were formed: one uninfected control group, one group infected with BSE prions, one with vCJD prions, and one with sCJD prions. Health of animals, infection, and progression to disease was looked at in our pathology department and in cooperation with W. Schulz-Schaeffer at the UMG (University Medicine, Göttingen). Besides, neurologists from the UMG also observed the animals whenever clinical symptoms seemed to appear. This close observation and comparison with human CJD cases demonstrated how close clinical progression of human disease resembles the experimental infection in the non-human primate.
2.2 Infection Infectious prions from brain tissue of one sCJD and one vCJD case (provided by J. Collinge) as well as BSE prions (from a “German” madcow case and provided by W. Schulz Schaeffer) were intraperitoneally administered into the rhesus monkeys.
2.3 Monitoring of behavior and telemetry Early behavioral monitoring was carried out by the ethologists I. Machatschke and J. Dittami from Vienna University. Transmitters were used to record changes in the circadian rhythms. Body temperature, sleep–wake cycles, and activity profiles could be obtained over a time span of 2 years. Up to half a year after infection animals did not show any signs of prion infection. However, after 6 months and persisting for another few months some animals had some disturbances in circadian rhythms which disappeared and then never appeared again(I. Machatschke, personal communication,2006).For a rather long time of about 4–5 years animals seemed to be healthy. But then, almost all animals rapidly progressed to symptoms. Symptoms were highly similar or even identical to those seen in human CJD.
2.4 Pathology Blood and necropsy specimens from the animals served as a valuable source to detect pathologically associated prion protein even in non-neuronal skeletal and cardiac tissue. These “hidden places” of prion pathology and replication were clearly demonstrated and extended our view where prions might spread within an organism. Not only leukocytes and neuronal tissue harbor abnormal prion protein isoforms but also other tissues can propagate prion protein isoforms leading to toxicity, cell degeneration, and eventually transmissible prions (Krasemann et al., 2010, 2013).
Most importantly, early signs of an altered circadian rhythm, sleep–wake cycle, and activity and body temperature were recorded in prion-infected animals. This experimental approach would have never been feasible in studies with human CJD cases. After 4–6 years animals developed clinical symptoms highly similar to those typical for CJD. Clinicians confirmed how close the animal model and the human disease matched. Non-neuronal tissue like cardiac muscle and peripheral blood with abnormal, disease-related prion protein were detected in rhesus monkey tissues.
PRION 2016 TOKYO
Zoonotic Potential of CWD Prions: An Update
Ignazio Cali1, Liuting Qing1, Jue Yuan1, Shenghai Huang2, Diane Kofskey1,3, Nicholas Maurer1, Debbie McKenzie4, Jiri Safar1,3,5, Wenquan Zou1,3,5,6, Pierluigi Gambetti1, Qingzhong Kong1,5,6 1Department of Pathology, 3National Prion Disease Pathology Surveillance Center, 5Department of Neurology, 6National Center for Regenerative Medicine, Case Western Reserve University, Cleveland, OH 44106, USA. 4Department of Biological Sciences and Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, 2Encore Health Resources, 1331 Lamar St, Houston, TX 77010
Chronic wasting disease (CWD) is a widespread and highly transmissible prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern, but the susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. We reported earlier that peripheral and CNS infections were detected in transgenic mice expressing human PrP129M or PrP129V. Here we will present an update on this project, including evidence for strain dependence and influence of cervid PrP polymorphisms on CWD zoonosis as well as the characteristics of experimental human CWD prions.
PRION 2016 TOKYO In Conjunction with Asia Pacific Prion Symposium 2016 PRION 2016 Tokyo Prion 2016
http://prion2016.org/dl/newsletter_03.pdf
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
LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
https://www.landesbioscience.com/journals/prion/article/28124/?nocache=112223249
How Did CWD Get Way Down In Medina County, Texas?
Confucius ponders...
Could the Scrapie experiments back around 1964 at Moore Air Force near Mission, Texas, could this area have been ground zero for CWD TSE Prion (besides the CWD cases that have waltzed across the Texas, New Mexico border near WSMR Trans Pecos region since around 2001)?
Epidemiology of Scrapie in the United States 1977
snip...
Scrapie Field Trial Experiments Mission, Texas
A Scrapie Field Trial was developed at Mission, Texas, to provide additional information for the eradication program on the epidemiology of natural scrapie. The Mission Field Trial Station is located on 450 acres of pastureland, part of the former Moore Air Force Base, near Mission, Texas. It was designed to bring previously exposed, and later also unexposed, sheep or goats to the Station and maintain and breed them under close observation for extended periods to determine which animals would develop scrapie and define more closely the natural spread and other epidemiological aspects of the disease.
The 547 previously exposed sheep brought to the Mission Station beginning in 1964 were of the Cheviot, Hampshire, Montadale, or Suffolk breeds. They were purchased as field outbreaks occurred, and represented 21 bloodlines in which scrapie had been diagnosed. Upon arrival at the Station, the sheep were maintained on pasture, with supplemental feeding as necessary. The station was divided into 2 areas: (1) a series of pastures and-pens occupied by male animals only, and (2) a series of pastures and pens occupied by females and young progeny of both sexes. ...
snip...see full text ;
http://web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
Thursday, June 09, 2016
Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie TSE Prion Experiment 1964
How Did CWD Get Way Down In Medina County, Texas?
http://chronic-wasting-disease.blogspot.com/2016/06/how-did-cwd-get-way-down-in-medina.html
http://scrapie-usa.blogspot.com/2016/06/scrapie-field-trial-experiments-mission.html
Friday, April 22, 2016
*** Texas Scrapie Confirmed in a Hartley County Sheep where CWD was detected in a Mule Deer
http://scrapie-usa.blogspot.com/2016/04/texas-scrapie-confirmed-in-hartley.html
*** Texas Scrapie Confirmed in a Hartley County Sheep where CWD was detected in a Mule Deer
http://scrapie-usa.blogspot.com/2016/04/texas-scrapie-confirmed-in-hartley.html
Thursday, December 08, 2016
USDA APHIS National Scrapie Eradication Program October 2016 Monthly Report Fiscal Year 2017 atypical NOR-98 Scrapie
Monday, April 04, 2016
Limited amplification of chronic wasting disease prions in the peripheral tissues of intracerebrally inoculated cattle
”The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite it’s subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA veiwed it as a wildlife problem and consequently not their province!” page 26.
Evidence That Transmissible Mink Encephalopathy Results from Feeding Infected Cattle
Over the next 8-10 weeks, approximately 40% of all the adult mink on the farm died from TME.
snip...
The rancher was a ''dead stock'' feeder using mostly (>95%) downer or dead dairy cattle...
http://collections.europarchive.org/tna/20090505194948/http://bseinquiry.gov.uk/files/mb/m09/tab05.pdf
http://collections.europarchive.org/tna/20090505194948/http://bseinquiry.gov.uk/files/mb/m09a/tab01.pdf
http://collections.europarchive.org/tna/20090505194948/http://bseinquiry.gov.uk/files/yb/1987/06/10004001.pdf
In Confidence - Perceptions of unconventional slow virus diseases of animals in the USA - APRIL-MAY 1989 - G A H Wells
3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs. ...
”The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite it’s subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA veiwed it as a wildlife problem and consequently not their province!” ...page 26.
http://collections.europarchive.org/tna/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.
http://collections.europarchive.org/tna/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
SPONTANEOUS ATYPICAL BOVINE SPONGIFORM ENCEPHALOPATHY
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Primate Biol., 3, 47–50, 2016 www.primate-biol.net/3/47/2016/ doi:10.5194/pb-3-47-2016 © Author(s) 2016. CC
Attribution 3.0 License.
Prions
Walter Bodemer German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany Correspondence to: Walter Bodemer (wbodemer@dpz.eu)
Received: 15 June 2016 – Revised: 24 August 2016 – Accepted: 30 August 2016 – Published: 7 September 2016
Abstract.
Prions gained widespread public and scientific interest in the year 2000. At that time, the human neurological Creutzfeldt–Jakob disease (CJD) was known. However, new CJD cases were diagnosed but they could not be ascribed to one of the classical CJD categories i.e. sporadic (sCJD), hereditary or acquired. Hence, they were classified as variant CJD (vCJD). Later on, experimental evidence suggested that vCJD was caused by prions postulated as unique novel infectious agents and, for example, responsible for bovine spongiform encephalopathy (BSE) also known as mad cow disease. The infection of humans by transmission of BSE prions also defined vCJD as a zoonotic disease. Prions, especially those associated with scrapie in sheep had been known for quite some time and misleadingly discussed as a slow virus. Therefore, this enigmatic pathogen and the transmission of this unusual infectious agent was a matter of a controversial scientific debate. An agent without nucleic acid did not follow the current dogma postulating DNA or RNA as inheritable information encoding molecules. Although numerous experimental results clearly demonstrated the infectious capacity of prions in several animal species, a model close to human was not readily available. Therefore, the use of rhesus monkeys (Macaca mulatta) served as a non-human primate model to elucidate prion infection under controlled experimental conditions. Not the least, transmission of BSE, human vCJD, and sCJD prions could be confirmed in our study. Any prion infection concomitant with progression of disease in humans, especially vCJD, could be analyzed only retrospectively and at late stages of disease. In contrast, the prion-infected rhesus monkeys were accessible before and after infection; the progression from early stage to late clinical stages – and eventually death of the animal–could be traced. Because of the phylogenetic proximity to humans, the rhesus monkey was superior to any rodent or other animal model. For these reasons an experimental approach had been conceived by J. Collinge in London and A. Aguzzi in Zurich and performed in a cooperative study with both research groups in the pathology unit of the German Primate Center (DPZ). The study in the DPZ lasted from 2001 until 2012. Our research in the pathology unit provided a temporal monitoring of how an initial prion infection develops eventually into disease; an approach that would have never been possible in humans since the time point of infection with prions from, for example, BSE is always unknown. Telemetry revealed a shift in sleep– wake cycles early on, long before behavioral changes or clinical symptoms appeared. Pathology confirmed nonneuronal tissue as hidden places where prions exist. The rhesus model also allowed first comparative studies of epigenetic modifications on RNA in peripheral blood and brain tissue collected from uninfected and prion infected animals. To conclude, our studies clearly demonstrated that this model is valid since progression to disease is almost identical to human CJD.
Published by Copernicus Publications on behalf of the Deutsches Primatenzentrum GmbH (DPZ).
SNIP...
2 Methods and results
2.1 Animals The reason to perform prion research in rhesus monkeys was to monitor infection and the temporal progression of prion infection in the rhesus monkey. In contrast to studies of human CJD cases, we could decide on the infectious dose. We also could control behavior immediately after prion inoculation and during the rather long time until animals died from the prion infection. Hidden places where prions might exist were found. Even epigenetic modifications on RNA could be detected. Taken together, these experimental approaches depended on animals. Using rhesus monkeys as a model system required thorough ethic reasoning and consultation with authorities before we actually turned to conduct the experiments. The Number of animals was limited just to fulfill statistical conditions. The individual health status was obtained and health care was provided throughout the study. The animals underwent daily inspection to monitor any changes in health and behavior. The experiments were conceived with the aim of reducing pain, suffering, and harm. Groups of animals were preferred in order to keep them in a social environment. The animals were originally kept in Vienna at Baxter and transferred to the German Primate Center (DPZ) in 2001. J. Collinge, A. Aguzzi, and C. Weissmann were the scientists who recommended this well-controlled prion infection study, and financial support was provided by an EU grant.To ensure statistical significance four groups consisting of four rhesus macaques each were formed: one uninfected control group, one group infected with BSE prions, one with vCJD prions, and one with sCJD prions. Health of animals, infection, and progression to disease was looked at in our pathology department and in cooperation with W. Schulz-Schaeffer at the UMG (University Medicine, Göttingen). Besides, neurologists from the UMG also observed the animals whenever clinical symptoms seemed to appear. This close observation and comparison with human CJD cases demonstrated how close clinical progression of human disease resembles the experimental infection in the non-human primate.
2.2 Infection Infectious prions from brain tissue of one sCJD and one vCJD case (provided by J. Collinge) as well as BSE prions (from a “German” madcow case and provided by W. Schulz Schaeffer) were intraperitoneally administered into the rhesus monkeys.
2.3 Monitoring of behavior and telemetry Early behavioral monitoring was carried out by the ethologists I. Machatschke and J. Dittami from Vienna University. Transmitters were used to record changes in the circadian rhythms. Body temperature, sleep–wake cycles, and activity profiles could be obtained over a time span of 2 years. Up to half a year after infection animals did not show any signs of prion infection. However, after 6 months and persisting for another few months some animals had some disturbances in circadian rhythms which disappeared and then never appeared again(I. Machatschke, personal communication,2006).For a rather long time of about 4–5 years animals seemed to be healthy. But then, almost all animals rapidly progressed to symptoms. Symptoms were highly similar or even identical to those seen in human CJD.
2.4 Pathology Blood and necropsy specimens from the animals served as a valuable source to detect pathologically associated prion protein even in non-neuronal skeletal and cardiac tissue. These “hidden places” of prion pathology and replication were clearly demonstrated and extended our view where prions might spread within an organism. Not only leukocytes and neuronal tissue harbor abnormal prion protein isoforms but also other tissues can propagate prion protein isoforms leading to toxicity, cell degeneration, and eventually transmissible prions (Krasemann et al., 2010, 2013).
SNIP...
3 Conclusion
Most importantly, early signs of an altered circadian rhythm, sleep–wake cycle, and activity and body temperature were recorded in prion-infected animals. This experimental approach would have never been feasible in studies with human CJD cases. After 4–6 years animals developed clinical symptoms highly similar to those typical for CJD. Clinicians confirmed how close the animal model and the human disease matched. Non-neuronal tissue like cardiac muscle and peripheral blood with abnormal, disease-related prion protein were detected in rhesus monkey tissues.
Molecular changes in RNA from repetitive Alu and BC200 DNA elements were identified and found to be targets of epigenetic editing mechanisms active in prion disease. To conclude, our results with the rhesus monkey model for prion disease proved to be a valid model and increased our knowledge of pathogenic processes that are distinctive to prion disease.
SEE FULL TEXT ;
*** WDA 2016 NEW YORK ***
We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions.
Student Presentations Session 2
The species barriers and public health threat of CWD and BSE prions
Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr. Edward Hoover1 1Colorado State University
Chronic wasting disease (CWD) is spreading rapidly through cervid populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease) arose in the 1980s because cattle were fed recycled animal protein. These and other prion diseases are caused by abnormal folding of the normal prion protein (PrP) into a disease causing form (PrPd), which is pathogenic to nervous system cells and can cause subsequent PrP to misfold. CWD spreads among cervids very efficiently, but it has not yet infected humans. On the other hand, BSE was spread only when cattle consumed infected bovine or ovine tissue, but did infect humans and other species. The objective of this research is to understand the role of PrP structure in cross-species infection by CWD and BSE. To study the propensity of each species’ PrP to be induced to misfold by the presence of PrPd from verious species, we have used an in vitro system that permits detection of PrPd in real-time. We measured the conversion efficiency of various combinations of PrPd seeds and PrP substrate combinations. We observed the cross-species behavior of CWD and BSE, in addition to feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions. CWD is unique among prion diseases in its rapid spread in natural populations. BSE prions are essentially unaltered upon passage to a new species, while CWD adapts to the new species. This adaptation has consequences for surveillance of humans exposed to CWD.
Wildlife Disease Risk Communication Research Contributes to Wildlife Trust Administration Exploring perceptions about chronic wasting disease risks among wildlife and agriculture professionals and stakeholders
http://www.wda2016.org/uploads/5/8/6/1/58613359/wda_2016_conference_proceedings_low_res.pdf
We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions.
Student Presentations Session 2
The species barriers and public health threat of CWD and BSE prions
Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr. Edward Hoover1 1Colorado State University
Chronic wasting disease (CWD) is spreading rapidly through cervid populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease) arose in the 1980s because cattle were fed recycled animal protein. These and other prion diseases are caused by abnormal folding of the normal prion protein (PrP) into a disease causing form (PrPd), which is pathogenic to nervous system cells and can cause subsequent PrP to misfold. CWD spreads among cervids very efficiently, but it has not yet infected humans. On the other hand, BSE was spread only when cattle consumed infected bovine or ovine tissue, but did infect humans and other species. The objective of this research is to understand the role of PrP structure in cross-species infection by CWD and BSE. To study the propensity of each species’ PrP to be induced to misfold by the presence of PrPd from verious species, we have used an in vitro system that permits detection of PrPd in real-time. We measured the conversion efficiency of various combinations of PrPd seeds and PrP substrate combinations. We observed the cross-species behavior of CWD and BSE, in addition to feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species. We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions. CWD is unique among prion diseases in its rapid spread in natural populations. BSE prions are essentially unaltered upon passage to a new species, while CWD adapts to the new species. This adaptation has consequences for surveillance of humans exposed to CWD.
Wildlife Disease Risk Communication Research Contributes to Wildlife Trust Administration Exploring perceptions about chronic wasting disease risks among wildlife and agriculture professionals and stakeholders
http://www.wda2016.org/uploads/5/8/6/1/58613359/wda_2016_conference_proceedings_low_res.pdf
PRION 2016 TOKYO
Zoonotic Potential of CWD Prions: An Update
Ignazio Cali1, Liuting Qing1, Jue Yuan1, Shenghai Huang2, Diane Kofskey1,3, Nicholas Maurer1, Debbie McKenzie4, Jiri Safar1,3,5, Wenquan Zou1,3,5,6, Pierluigi Gambetti1, Qingzhong Kong1,5,6 1Department of Pathology, 3National Prion Disease Pathology Surveillance Center, 5Department of Neurology, 6National Center for Regenerative Medicine, Case Western Reserve University, Cleveland, OH 44106, USA. 4Department of Biological Sciences and Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, 2Encore Health Resources, 1331 Lamar St, Houston, TX 77010
Chronic wasting disease (CWD) is a widespread and highly transmissible prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern, but the susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. We reported earlier that peripheral and CNS infections were detected in transgenic mice expressing human PrP129M or PrP129V. Here we will present an update on this project, including evidence for strain dependence and influence of cervid PrP polymorphisms on CWD zoonosis as well as the characteristics of experimental human CWD prions.
PRION 2016 TOKYO In Conjunction with Asia Pacific Prion Symposium 2016 PRION 2016 Tokyo Prion 2016
http://prion2016.org/dl/newsletter_03.pdf
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
*** 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
Saturday, April 23, 2016
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
WS-01: Prion diseases in animals and zoonotic potential
Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a,
Natalia Fernandez-Borges a. and Alba Marin-Moreno a
"Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France
Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion. Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier.
To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents.
These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant.
Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with ef?ciency comparable to that of cattle BSE. While the ef?ciency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
WS-01: Prion diseases in animals and zoonotic potential
Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a,
Natalia Fernandez-Borges a. and Alba Marin-Moreno a
"Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France
Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion. Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier.
To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents.
These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant.
Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with ef?ciency comparable to that of cattle BSE. While the ef?ciency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
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
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
Title: Transmission of scrapie prions to primate after an extended silent incubation period)
*** 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.
*** 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
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
http://scrapie-usa.blogspot.com/2016/04/scrapie-ws-01-prion-diseases-in-animals.html
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
http://scrapie-usa.blogspot.com/2016/04/scrapie-ws-01-prion-diseases-in-animals.html
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
LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
https://www.landesbioscience.com/journals/prion/article/28124/?nocache=112223249
*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, and there may be asymptomatic individuals infected with the CWD equivalent. These circumstances represent a potential threat to blood, blood products, and plasma supplies.
http://cdmrp.army.mil/prevfunded/nprp/NPRP_Summit_Final_Report.pdf
http://cdmrp.army.mil/prevfunded/nprp/NPRP_Summit_Final_Report.pdf
Terry S. Singeltary Sr.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.