Evidence of scrapie transmission to sheep via goat milk
Evidence of scrapie transmission to sheep via goat milk
Timm KonoldEmail author, Leigh Thorne, Hugh A. Simmons, Steve A. C.
Hawkins, Marion M. Simmons and Lorenzo González
BMC Veterinary ResearchBMC series – open, inclusive and
trusted201612:208
DOI: 10.1186/s12917-016-0807-4
© Crown copyright; licensee BioMed Central Ltd. 2016
Received: 29 April 2016
Accepted: 19 August 2016
Published: 17 September 2016
Abstract
Background
Previous studies confirmed that classical scrapie can be transmitted via
milk in sheep. The current study aimed to investigate whether scrapie can also
be transmitted via goat milk using in vivo (new-born lambs fed milk from
scrapie-affected goats due to the unavailability of goat kids from guaranteed
scrapie-free herds) and in vitro methods (serial protein misfolding cyclic
amplification [sPMCA] on milk samples).
Results
In an initial pilot study, new-born lambs of two different prion protein
gene (PRNP) genotypes (six VRQ/VRQ and five ARQ/ARQ) were orally challenged with
5 g brain homogenate from two scrapie-affected goats to determine susceptibility
of sheep to goat scrapie. All sheep challenged with goat scrapie brain became
infected based on the immunohistochemical detection of disease-associated PrP
(PrPsc) in lymphoid tissue, with an ARQ/ARQ sheep being the first to succumb.
Subsequent feeding of milk to eight pairs of new-born ARQ/ARQ lambs, with each
pair receiving milk from a different scrapie-affected goat, resulted in scrapie
in the six pairs that received the largest volume of milk (38–87 litres per
lamb), whereas two pairs fed 8–9 litres per lamb, and an environmental control
group raised on sheep milk from healthy ewes, did not show evidence of infection
when culled at up to 1882 days of age. Infection in those 12 milk recipients
occurred regardless of the clinical status, PrPsc distribution, caprine
arthritis-encephalitis virus infection status and PRNP polymorphisms at codon
142 (II or IM) of the donor goats, but survival time was influenced by PRNP
polymorphisms at codon 141. Serial PMCA applied to a total of 32 milk samples
(four each from the eight donor goats collected throughout lactation) detected
PrPsc in one sample each from two goats.
Conclusions
The scrapie agent was present in the milk from infected goats and was able
to transmit to susceptible species even at early preclinical stage of infection,
when PrPsc was undetectable in the brain of the donor goats. Serial PMCA as a
PrPsc detection method to assess the risk of scrapie transmission via milk in
goats proved inefficient compared to the bioassay.
Keywords Transmissible spongiform encephalopathy – Scrapie – Goat – Sheep –
Milk – Colostrum – Transmission – Protein misfolding cyclic amplification –
Prion protein – Genotype
see full text ;
***Importantly, infectious prions are present in the brain, bodily fluids
and excreta of animals showing no clinical signs of TSE [32]–[37]. For example,
the blood, saliva and urine from deer subclinically infected with CWD contain
infectious prions [32], [38], [39]. Race and coworkers [40] found a long-term
subclinical carrier state in mice infected with hamster scrapie. Atypical BSE
(BASE) can be transmitted from non-clinical cattle to primates [41] and cattle
exposed to large oral doses of BSE can remain free of clinical signs but are
found to harbor infectious prions upon bioassay into bovid PrP transgenic mice
[42]. Taken together, these findings suggest that carriers without clinical
signs exist and may transmit infection to their offspring via milk,
transplacental trafficking or blood. http://journals.plos.org/plosone/article/asset?id=10.1371/journal.pone.0071844.PDF
http://transmissiblespongiformencephalopathy.blogspot.com/2013/09/mother-to-offspring-transmission-of.html
PRION PROTEIN IN MILK
Sun Jan 14, 2007 20:5771.248.156.194
Subject: Prion Protein in Milk Date: January 14, 2007 at 5:41 pm PST PLoS
ONE. 2006; 1(1): e71. Published online 2006 December 20. doi:
10.1371/journal.pone.0000071. Copyright Franscini et al. This is an open-access
article distributed under the terms of the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium,
provided the original author and source are credited.
Prion Protein in Milk
Nicola Franscini,1 Ahmed El Gedaily,1 Ulrich Matthey,1 Susanne Franitza,1
Man-Sun Sy,2 Alexander Bürkle,3 Martin Groschup,4 Ueli Braun,5 and Ralph Zahn1*
1Alicon AG, Schlieren, Switzerland 2Institute of Pathology, Biomedical
Research Building, Case Western University School of Medicine, Cleveland, Ohio,
United States of America 3Lehrstuhl Molekulare Toxikologie, University of
Konstanz, Konstanz, Germany 4Friedrich-Loeffler-Institut,
Bundesforschungsinstitut für Tiergesundheit, Greifswald, Gemany 5Departement für
Nutztiere, University of Zurich, Zurich, Switzerland Matthew Baylis, Academic
Editor
University of Liverpool, United Kingdom
* To whom correspondence should be addressed. E-mail: info@alicon.ch
Conceived and designed the experiments: ZR FN EA MU FS RZ NF AE UM SF. Performed
the experiments: FN EA MU FS NF AE UM SF. Analyzed the data: ZR FN EA MU FS RZ
NF AE UM SF. Contributed reagents/materials/analysis tools: AB MG SM BA GM BU MS
UB. Wrote the paper: AB MG ZR FN BA GM BU RZ NF UB.
Received October 19, 2006; Accepted November 6, 2006.
ABSTRACT
Background Prions are known to cause transmissible spongiform
encephalopathies (TSE) after accumulation in the central nervous system. There
is increasing evidence that prions are also present in body fluids and that
prion infection by blood transmission is possible. The low concentration of the
proteinaceous agent in body fluids and its long incubation time complicate
epidemiologic analysis and estimation of spreading and thus the risk of human
infection. This situation is particularly unsatisfactory for food and
pharmaceutical industries, given the lack of sensitive tools for monitoring the
infectious agent.
Methodology/Principal Findings We have developed an adsorption matrix,
Alicon PrioTrap®, which binds with high affinity and specificity to prion
proteins. Thus we were able to identify prion protein (PrPC)–the precursor of
prions (PrPSc)–in milk from humans, cows, sheep, and goats. The absolute amount
of PrPC differs between the species (from µg/l range in sheep to ng/l range in
human milk). PrPC is also found in homogenised and pasteurised off-the-shelf
milk, and even ultrahigh temperature treatment only partially diminishes
endogenous PrPC concentration.
Conclusions/Significance In view of a recent study showing evidence of
prion replication occurring in the mammary gland of scrapie infected sheep
suffering from mastitis, the appearance of PrPC in milk implies the possibility
that milk of TSE-infected animals serves as source for PrPSc.
INTRODUCTION
SNIP...
DISCUSSION
Milk contributes 13% to the worldwide protein supply for humans. World milk
production ranges around 500 million tons a year. Before fresh milk reaches the
consumer, it is usually homogenized to reduce fat particle size in order to
increase digestibility of the milk and heated. Surprisingly, pasteurisation
(heating for 30 seconds to 72°C) and ultra-high temperature treatment (heating
for 1–4 seconds to 135°C) only leads to a partial reduction of the amount of
PrPC. This supports the observation that PrPC is highly stable in milk. Thus,
the heating procedures used to inactivate DNA-containing pathogens are not
sufficient to eliminate endogenous prion proteins.
The presence of PrPC in blood has been documented [14], [15], and is
confirmed by our own unpublished observations. To produce one liter of milk,
about 400 to 500 liters of blood must pass through the udder of a cow. It is
thus possible that the PrPC found in milk derives from blood cells or,
alternatively, has been secreted from glandular epithelial cells. Cell types
that have been identified in milk from healthy cows are mainly macrophages, and
other leucocytes. However, in our assay cells are completely removed by
centrifugation. Therefore, the recovered PrPC is not cell associated but most
likely binds to other proteins or lipids resulting in stable molecular
complexes. The fact that milk contains full-length PrPC, very likely comprising
the glycolipid anchor, indicates that prion protein was originally cell-bound
and does not represent any of the amino-terminal truncation products of PrPC
known to be released from normal cells under physiological conditions [25]. The
detection of such a considerable expression of cell membrane bound or derived
PrPC in milk constitutes one of the key requirements for the generation of
infectious prions in the udder of infected animals.
Over the last 10 years, scientific groups, risk assessment agencies, and
public health organizations have debated the TSE risk for milk and milk products
[26], [27]. Epidemiological and bioassay data so far available have not provided
evidence for milk to harbour prion infectivity and infectious prions have as yet
not been detected by bioassays in the milk, colostrum or udder of clinical BSE
cases in cow [18]–[21]. However, a recent statement of the European Food Safety
Authority affirmed that based on a number of observations from research data,
there are indications that infectivity in the milk from small ruminants can not
be totally excluded [28]. Furthermore, the exclusion of animals with mastitis,
an inflammation of the mammal gland, being able to destabilize the blood-milk
barrier, is considered a measure able to reduce but not to eliminate the
potential contamination risk [28]. The rational of this conclusion is confirmed
by a recent study showing that in sheep naturally affected with both scrapie and
lymphocyte or lymphofollicular mastitis, PrPSc accumulation was present in
lymphoid follicles adjacent to milk ducts [29]. At least in natural sheep
scrapie, prion replication can occur following a lymphotropic virus infection in
the inflamed mammary gland. This study has not detected PrPSc or prion
infectivity in milk itself. However, since under such inflammatory conditions,
the total number of immune cells increases in milk of animals, it might be
possible that infectious PrPSc is also passing through and reaches the milk. In
this context milk from such animals could possibly be responsible for the spread
of scrapie from the ewes to their offspring in affected sheep or goat flocks.
Moreover, sheep and goat milk could also constitute a TSE exposure risk for
mammals (humans) consuming these products.
The former Scientific Steering committee of the European Commission and the
European Food Safety Authority recommend that research should intensify on the
safety of milk of small ruminants with regard to TSE risk. Limited new data are
expected to be published in the near future and there is still little research
initiated in this area [28]. The Alicon PrioTrap® technology opens a new avenue
for studying the biochemical characteristics of prion protein in milk and thus
may contribute to offer a feasible approach to perform an appropriate study on
the milk safety with regard to TSE risk.
SNIP...
FIGURES AND TABLES ........SNIP.........END
Re: PRION PROTEIN IN MILK Mon Jan 15, 2007 12:19 71.248.156.194
> Thus we were able to identify prion protein (PrPC)–the precursor
of
> prions (PrPSc)–in milk from humans, cows, sheep, and goats.
snip...
> Conclusions/Significance
> In view of a recent study showing evidence of prion replication
occurring in the mammary gland of scrapie
> infected sheep suffering from mastitis, the appearance of PrPC in milk
implies the possibility that milk of
> TSE-infected animals serves as source for PrPSc.
TO DATE, BSE has not been detectable in milk. NOW, what about BASE and or
atypical TSE in bovine? well, that's another question. and with testing in the
pipeline that is much more sensistive, yet to be validated, low level TSE
infectivity in milk is still very much possible. then, what about accumulation ?
well, we all can hope that we die from old age first. PrPSc HAS been detected in
mammary glands of sheep affected by scrapie and mastitis. ...tss
studies of interest ;
SEAC 90th meeting held on the 24th Nov $ THE vCJD EPIDEMIC Thu Dec 1, 2005
10:23 70.110.89.187
1
© SEAC 2005
NINETIETH MEETING OF THE SPONGIFORM
ENCEPHALOPATHY ADVISORY COMMITTEE
The Spongiform Encephalopathy Advisory Committee held its 90th
meeting in Edinburgh on 24th November 2005, and discussed the
following matters:
CURRENT ISSUES
SEAC was informed about the following issues:
• The SEAC Sheep Subgroup will meet on 24th January 2006
to consider emerging scientific developments on atypical
scrapie and possible implications for the National Scrapie
Plan (NSP) and EU TSE roadmap.
• A recent article1 reporting detection of relatively low levels of
abnormal prion in the mammary glands of five Italian farmed
sheep with coincident clinical signs of natural scrapie and
mastitis. Abnormal prion protein was absent in the
mammary gland of sheep free of mastitis or scrapie. SEAC
agreed that the study provided further evidence that
inflammatory diseases can alter the distribution of abnormal
prion protein in infected animals. However, the particular
form of mastitis was rare in the UK and the sheep breed
studied is prone to particular diseases. SEAC considered
the study to be important. However, it would be premature to
come to firm conclusions about the possible implications of
the findings for UK flocks and further investigations should
be undertaken. It was noted that regulations restrict milk
from animals with clinical mastitis from entering the food
chain.
1 Ligios et al. (2005) PrPSc in mammary glands of sheep affected by
scrapie
and mastitis. Nature Medicine, 11 published online 04/11/05.
2
© SEAC 2005
snip.......end
see full text here ;
PrPSc in mammary glands of sheep affected by scrapie and mastitis. Ligios
C, Sigurdson CJ, Santucciu C, Carcassola G, Manco G, Basagni M, Maestrale C,
Cancedda MG, Madau L, Aguzzi A.
2006
"Occurrence and Stability of the BSE Agent in Foodstuff (primarily in Milk
and Milk Products) and in the Environment" For the protection of the consumer a
scientifically based risk assessment of animal derived products, particularly
milk, meat and products thereof is of prime importance. The knowledge on BSE in
this regard is insufficient and also this topic is at present not taken into
account in the EU projects on transmissible spongiform encephalopathies. It is
also unknown at present, if and to what degree the BSE prions, considered to be
very stable, can be degraded or inactivated by microbial processes in the
gastrointestinal tract of animals, by fermentation processes during food
processing and by the complex microflora of the environment. The project
therefore aims at the improvement of food safety as well as the protection of
the consumer and the environment. In order to create the scientific base for a
quantitative risk assessment, the following tasks will be solved using modern
trace analytical, microbiological and molecular biological methods.
1) Sensitive detection methods for PrPSc in bovine body fluids shall be
developed with the main emphasis on the detection of small amounts of the agent
in milk but also in blood and meat dripping juice.
2) The microbial degradation of PrPSc shall be studied in order to gain
basic knowledge on the stability and fate of the BSE agent in the
gastrointestinal tract, in the environment (soil) and in foodstuff (milk and
meat products).
Application:
Scientific basis for a rik assessment for food
URL:
Project partners:
Bundesanstalt für Fleischforschung - Institut für Mikrobiologie und
Toxikologie TU München - Institut für Mikrobiologie, Forschungszentrum für Milch
und Lebensmittel Weihenstephan BFAV - Institut für neue und neuartige
Tierseuchenerreger LMU München - Lehrstuhl für Hygiene und Technologie der Milch
Publications:
Biochemical evidence for the proteolytic degradation of infectious prion
protein PrPSc in hamster brain homogenates by foodborne bacteria Müller-Hellwig
S, Groschup MH, Pichner R, Gareis M, Märtlbauer E, Scherer S, Loessner MJ Syst
Appl Microbiol 2006 Mar; 29 (2): 165-71
Degradation of scrapie associated prion protein (PrPSc) by the
gastrointestinal microbiota of cattle Christina Scherbel, Rohtraud Pichner,
Matin H.Groschup, Simone Mueller.Hellwig, Siegfried Scherer, Richard Dietrich,
Erwin Maertlbauer, Manfred Gareis Vet Res. 37 (2006) 695-703
Cellular Prion Protein in the Bovine Mammary Gland Is Selectively Expressed
in Didier A, Dietrich R, Steffl M, Gareis M, Groschup MH, Muller-Hellwig S, J
Histochem Cytochem. 2006 Jul 24; [Epub ahead of print]
Prion protein expression in bovine podocytes and extraglomerular mesangial
Amselgruber WM, Steffl M, Didier A, Martlbauer E, Pfaff E, Buttner M. Cell
Tissue Res. 2006 Jun;324(3):497-505. Epub 2006 Feb 17
Relevant Branches:
food technology health
SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE
Minutes of the open session of the 88th meeting held on 30th June
2005
ITEM 4 – RESEARCH ON ABNORMAL PRIONS IN BOVINE MILK
(SEAC 88/2)
starts at page 6 of 21.......tss
2001
Risk of TSE infection through milk There never has been any evidence of
milk as a method of transfer of scrapie and experiments in which a ewe with
scrapie was suckled by the offspring of another sheep showed no indication that
any risk was present. However, it would be surprising if there was no infection
present in milk at all simply because of the number of white cells that are
present in the milk. At the moment there are no useful inoculation studies
published that look for milk infectivity adequately.
-------------------------------------------------------------------
No evidence for BSE transmission through milk
(17.5.99 as a press release by Consumer Safety and Food)
The Scientific Steering Committee (SSC) sees no evidence for transmission
of BSE through milk. Hence, there is no reason for restriction on the use of
milk, stated the 16 independent scientists in an opinion on possible vertical
transmission of BSE (from mother to calf) on Friday. The higher infection rate
of calves from BSE-infected cows of between 5 and 15% is rather to be found in
other routes of contagion. The definite mechanisms for vertical transmission
still need to be clarified, they said. With respect to these mechanisms, the SSC
considers that transmission of BSE by artificial insemination is unlikely for
semen derived from BSE-affected bulls early in their incubation period and that
transmission of BSE via embryos is unlikely provided International Embryo
Transfer Society protocols are used.
However, the experts stated that - as a precautionary measure - milk from
BSE-affected cows should be taken out, although this milk is not proven to be
infectuous. The safety of milk is permanently monitored by the SSC. The
Committee also put a preliminary opinion on the recycling of fallen stock, dead
animals (including also ruminants, pigs, poultry, fish, wild/zoo/exotic animals,
laboratory animals, fish, fur animals and cats) and condemned materials, i.e.
animals not fit for human consumption onto internet for comments of interested
parties. With respect to the high risks of TSEs and unconventional, not yet
identified infectious agents, the present industrial processes of inactivating
conventional infectious agents could not be considered safe enough. The
scientists recommend that animals and SRMs with TSE or suspected of being so,
should be incinerated or burned after rendering and not be recycled for any
direct or indirect use, including use in cosmetics, pharmaceutical or medical
products and devises. The opinion and the preliminary opinion will shortly be
available under the following address :
However one of the additions to the SSC report was: "Regarding inoculating
cattle i/c with milk, the following comment can be made: In practice it might
prove to be more appropriate / useful to look (also) at certain fractions of
milk and to use transgenic mice rather than cattle once the model is proven. The
aim of the experiments should be to improve the confidence that milk and
colostrum do not transmit BSE. Colostrum is more important in the context of
protecting animal health and eventually eliminating BSE and thus a BSE source
for humans."
--------------------------------------------------------------------------
Safety of milk with regard to TSE: State of affairs (From Food Safety
announcement, 2001) 1. Summary
a. Because of the recent evidence of BSE being present in a number of
countries where it had not been detected until recently, Commission services are
frequently invited to express their opinion on the security status of ruminant
milk as a possible source of TSE infectivity.
b. The experimental evidence so far of bovine milk being safe with regard
to BSE risk has been questioned because these experiments were carried out on
mice; it was considered1 that these tests may have underestimated any possible
risk because of the species barrier from cows to mice. It is noted that milk had
the potential to transmit prion diseases like BSE because it contains a
significant component of leucocytes.
The Commission services therefore invited the Scientific Steering Committee
(SSC) to prepare a state of affairs regarding the available knowledge and
evidence on the safety of milk with regard to TSE risk.
On the basis of the discussion of a report prepared by the TSE/BSE ad hoc
Group, the Scientific Steering Committee (SSC) considers that the conclusions of
the Scientific Veterinary Committee (E.C., 1996), the Multidisciplinary
Scientific Committee (E.C., 1997) and itself (E.C., 1999), remain valid and that
the evidence available to date does not point at milk or colostrum representing
a possible risk. The SSC also supports the recommendation that for precautionary
reasons the milk, colostrum or milk products from suspect BSE cases should not
be offered for consumption.
No final results of further experiments became recently available and the
SSC confirms the recommendations for research made in each of the previously
listed scientific opinions.
2. Report from the TSE/BSE ad hoc Group
The TSE/BSE ad hoc Group reviewed the information and evidence available to
date. The state-of-affairs report prepared at its meeting of 15 March 2001 on
the basis of contributions from various scientists (see section 3) is presented
hereafter.
2.1 The Report of the Scientific Veterinary Committee of 1996 (E.C.,
1997)
In its opinion of 1996, the Scientific Veterinary Committee, "having
examined the considerable epidemiological and infectivity data pertaining to
BSE, maternal transmission and milk, concludes that bovine milk from healthy
cows and products derived therefrom which contain no animal-derived additives
can be safely consumed in any form by any species. There is no evidence that
milk transmits BSE and the Committee considers any risk from milk to be
negligible".
"In regard to colostrum, [the Committee] regarded any risks to be
negligible." It further recommended a "Prohibition on the use of milk (or
colostrum) or any product derived from these commodities from any cow clinically
suspected to have BSE for any nutritional or other purpose. An exception for the
suspect's own calf can be made" (...).
2.2. The scientific opinion of the Multidisciplinary Scientific Committee
of 1997 (Will, 1997, E.C., 1997b).
The evidence contained in the full report of the Scientific Veterinary
Committee (E.C., 1996) was reviewed in 1997 by the Multidisciplinary Scientific
Committee (Will, 1997; E.C., 1997) that concurred with the 1996
conclusions.
A maternal cohort study provided statistical evidence of a maternal risk
enhancement (e.g., Donnelly et al, 1997a, b)2, but did not provide evidence on
the risk of transmission by milk as the calves in this study received only
colostrum from their dams and as other explanations than vertical transmission
(for example peri-natal conditions) could not be excluded.
A serious hint that milk does not transmit the disease was the beef suckler
study (Wilesmith and Ryan, 1997, 1998; Donnelly, 1998) where no cases were
reported although all of them received colostrum and milk.
2.3. The SSC opinion on vertical transmission (1999)
In its opinion of 18-19 March 1999 on The possible vertical transmission of
Bovine Spongiform Encephalopathy (BSE), the SSC referred as follows to the work
of the UK Spongiform Encephalopathy Advisory Committee (SEAC):
"As regards the risks from bovine milk, the Scientific Steering Committee
refers to the continuous review by the UK Spongiform Encephalopathy Advisory
Committee (SEAC). SEAC has regularly discussed the safety of bovine milk in
regard to BSE, the last time on 9 November 1998. The latest substantive SEAC
view, expressed on 16 April 1997, was that the measures currently in place to
protect the consumer were considered appropriate. (UK law states that milk
derived from BSE affected cattle or cattle suspected to have BSE shall not be
sold, supplied or used for human or animal consumption, with the exception that
it may be fed to the cow's own calf.) SEAC concluded then (16/4/97) that no
evidence had been found to suggest that milk from any species affected by
transmissible spongiform encephalopathies was infectious. The Committee is
keeping the possible risk infectivity in milk under review and stated most
recently on 14 May 1998 that there was no reason to change their previous advice
on the safety of milk. This advice may need to be updated as new data and
information become available.
However, the Scientific Steering Committee notes that, in the absence of
any infectivity studies on semen, embryos, fetal tissue, milk and colostrum by
i/c inoculation of the homologous species in bovines, ovines and caprines, and
in the absence of all the necessary experimental and epidemiological data as
detailed in the report, precise estimates of these risks cannot be made."
2.4. Summary of presently available evidence (March 2001):
a. To date, the infectious agent has not been detected by mice bioassay of
milk from humans with kuru or CJD or from cattle with BSE3 or sheep with
scrapie.
b. To date, no mother to child transmissions have occurred in any animal
species used in experimental studies (including primates).
c. One single case has been reported on in 1992 of a 38-year-old pregnant
woman with sporadic CJD whose colostrum was found to be infected when injected
i/c into mice (Tamai et al, 1992). However, following further morphological
examination of fixed mouse brain by immunohistochemistry for PrPSc , the
Japanese authorities concluded tha
==============================
Re: PRION PROTEIN IN MILK
Sun Jan 14, 2007 20:5871.248.156.194
Immunochemical PrPC detection
Concentrated milk and brain PrPC was denaturated in SDS sample buffer and
heated at 70°C for 10 min and at 95°C for 5 min, respectively. Samples were
applied to a 12% SDS polyacrylamide gel for electrophoresis and subsequently
transferred to a PVDF membrane. The membrane was blocked with 2% ECL Advance™
blocking agent (Amersham) if probed with 8B4 antibody or 1% bovine serum albumin
if probed with other antibodies used in this study. 8B4 antibody was incubated
at a concentration of 450 ng/ml, 8H4 at 85 ng/ml, 6H4 at 285 ng/ml, and
anti-Tau-1 at 50 ng/ml. Sheep anti-mouse IgG horseradish peroxidase-conjugated
secondary antibody (Amersham) was incubated at a 1/20,000 dilution. The
immunoreactivity was visualized by chemiluminesecence detection following the
manufacture's instruction (ECL Advance Western Blot detection Kit, Amersham).
PNGase treatment of milk and brain PrPC For PNGase treatment prion protein
extracted from 10 ml cow milk or 10 µl of 1% (w/v) cow brain homogenate was
incubated for 12 h at 37°C in buffer containing 100 mM sodium phosphate, 10 mM
Tris-HCl, 1% NP-40, 1% MEGA-8, pH 8, and 1.5 units of N-Glycosidase F (Roche).
Under more stringent cleavage conditions, proteins were denatured by heating for
10 minutes at 100°C in the presence of 0.5% SDS before treatment with 4 units of
N-Glycosidase F.
Total milk protein detection A milk volume corresponding to 40 µg total
protein (1 µl) was heated in SDS loading buffer at 70°C for 10 min. After
electrophoresis on a 12% SDS polyacrylamide gel, the proteins were detected by
silver staining (SilverSNAP Stain kit II, Pierce).
Acknowledgments
We thank Theo Bearth, Roland Ermini, Peter May, Günter Kreissel, and
Mathias Schmid for their generous support. We are grateful to Torsten Seuberlich
from the NeuroCenter of the University of Bern for kindly providing us brain
homogenate from cattle.
Footnotes
Competing Interests: The authors have declared that no competing interests
exist. Funding: The authors have no support or funding to report.
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the analysis of normal prion protein in human blood and its components. Vox
Sang. 1999;77:88–92. [PubMed] 15.Barclay GR, Houston EF, Halliday SI, Farquhar
CF, Turner ML. Comparative analysis of normal prion protein expression in human,
rodent, and ruminant blood cells by using a panel of prion antibodies.
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Creutzfeldt-Jakob disease: risk of transmission by blood and blood products.
Haemophilia. 2004;10(Suppl 4):64–69. [PubMed] 17.Castilla J, Saa P, Soto C.
Detection of prions in blood. Nat Med. 2005;11:982–985. [PubMed] 18.Hadlow WJ,
Kennedy RC, Race RE, Eklund CM. Virologic and neurohistologic findings in dairy
goats affected with natural scrapie. Vet Pathol. 1980;17:187–199. [PubMed]
19.Bradley R, Wilesmith JW. Epidemiology and control of bovine spongiform
encephalopathy (BSE). Br Med Bull. 1993;49:932–959. [PubMed] 20.Taylor DM,
Ferguson CE, Bostock CJ, Dawson M. Absence of disease in mice receiving milk
from cows with bovine spongiform encephalopathy. Vet Rec. 1995;136:592. [PubMed]
21.Buschmann A, Groschup MH. Highly bovine spongiform encephalopathy-sensitive
transgenic mice confirm the essential restriction of infectivity to the nervous
system in clinically diseased cattle. J Infect Dis. 2005;192:934–942. [PubMed]
22.Li R, Liu T, Wong BS, Pan T, Morillas M, et al. Identification of an epitope
in the C terminus of normal prion protein whose expression is modulated by
binding events in the N terminus. J Mol Biol. 2000;301:567–573. [PubMed]
23.Korth C, Stierli B, Streit P, Moser M, Schaller O, et al. Prion
(PrPSc)-specific epitope defined by a monoclonal antibody. Nature.
1997;390:74–77. [PubMed] 24.Zanusso G, Liu D, Ferrari S, Hegyi I, Yin X, et al.
Prion protein expression in different species: analysis with a panel of new
mAbs. Proc Natl Acad Sci USA. 1998;95:8812–8816. [PubMed] 25.Laffont-Proust I,
Faucheux BA, Hassig R, Sazdovitch V, Simon S, et al. The N-terminal cleavage of
cellular prion protein in the human brain. FEBS Lett. 2005;579:6333–6337.
[PubMed] 26.EC. Scientific Veterinary Committee, Report on the risk analysis for
colostrium, milk, and milk products (Document N° VI/8197/96 Version J, Final,
1997). 27.EC. Multidisciplinary Scientific Committee, Opinion on the possible
risks related to the use of colostrium, milk and products (1997). 28.Statement
of the European Food Safety Authority Scientific Expert Working Group on BSE/TSE
of the Scientific Panel on Biological Hazards on the health risks of the
consumption of milk and milk derived products from goats (2004). Last updated
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FIGURES AND TABLES ........SNIP.........END
Monday, September 05, 2016
*** Pathological features of chronic wasting disease in reindeer and
demonstration of horizontal transmission Major Findings for Norway
Wednesday, September 7, 2016
*** An assessment of the long-term persistence of prion infectivity in
aquatic environments ***
Sunday, August 24, 2008
HAVE ANOTHER GLASS OF CWD PRIONS COURTESY Dane County Wisconsin Mike
DiMaggio, solid waste manager
Friday, September 02, 2016
Chronic Wasting Disease Drives Population Decline of White-Tailed
Deer
Saturday, September 17, 2016
Texas Parks Wildlife Chronic Wasting Disease CWD Management and Regulations
for Hunters 2016 – 2017
Monday, August 29, 2016
NWHC USGS CHRONIC WASTING DISEASE CWD TSE PRION UPDATE
Sunday, August 28, 2016
CONFIDENTIAL
Transmissible Spongiform Encephalopathy TSE Prion and how Politics and
Greed by the Industry spread madcow type diseases from species to species and
around the globe
TSE PRIONS AKA MAD COW TYPE DISEASE, LIONS AND TIGERS AND BEARS, OH MY!
Saturday, December 12, 2015
NOTICE: Environmental Impact Statement on Large Livestock Carcasses TSE
Prion REPORT December 14, 2015
Friday, August 14, 2015
Carcass Management During a Mass Animal Health Emergency Draft Programmatic
Environmental Impact Statement—August 2015
food for thought, specified risk materials srm’s, TSE Prions
anyone...
Thursday, August 25, 2016
FSIS Green Bay Dressed Beef Recalls Beef Products Due To Possible Specified
Risk Materials Contamination the most high risk materials for BSE TSE PRION AKA
MAD COW TYPE DISEASE
Tuesday, December 16, 2014
Evidence for zoonotic potential of ovine scrapie prions
Hervé Cassard,1, n1 Juan-Maria Torres,2, n1 Caroline Lacroux,1, Jean-Yves
Douet,1, Sylvie L. Benestad,3, Frédéric Lantier,4, Séverine Lugan,1, Isabelle
Lantier,4, Pierrette Costes,1, Naima Aron,1, Fabienne Reine,5, Laetitia
Herzog,5, Juan-Carlos Espinosa,2, Vincent Beringue5, & Olivier
Andréoletti1, Affiliations Contributions Corresponding author Journal name:
Nature Communications Volume: 5, Article number: 5821 DOI:
doi:10.1038/ncomms6821 Received 07 August 2014 Accepted 10 November 2014
Published 16 December 2014 Article tools Citation Reprints Rights &
permissions Article metrics
Abstract
Although Bovine Spongiform Encephalopathy (BSE) is the cause of variant
Creutzfeldt Jakob disease (vCJD) in humans, the zoonotic potential of scrapie
prions remains unknown. Mice genetically engineered to overexpress the human
prion protein (tgHu) have emerged as highly relevant models for gauging the
capacity of prions to transmit to humans. These models can propagate human
prions without any apparent transmission barrier and have been used used to
confirm the zoonotic ability of BSE. Here we show that a panel of sheep scrapie
prions transmit to several tgHu mice models with an efficiency comparable to
that of cattle BSE. The serial transmission of different scrapie isolates in
these mice led to the propagation of prions that are phenotypically identical to
those causing sporadic CJD (sCJD) in humans. These results demonstrate that
scrapie prions have a zoonotic potential and raise new questions about the
possible link between animal and human prions.
Subject terms: Biological sciences• Medical research At a glance
*** 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.
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 efficiency comparable to that of cattle BSE. While the
efficiency 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.
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
SCRAPIE AND CWD ZOONOSIS
PRION 2016 CONFERENCE 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
Transmission of scrapie prions to primate after an extended silent
incubation period
***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.***
Thursday, August 18, 2016
*** PROCEEDINGS ONE HUNDRED AND Nineteenth ANNUAL MEETING of the USAHA BSE,
CWD, SCRAPIE, PORCINE TSE PRION October 22 28, 2015 ***
Tuesday, August 9, 2016
*** Concurrence with OIE Risk Designations for Bovine Spongiform
Encephalopathy [Docket No. APHIS-2015-0055]
Saturday, July 23, 2016
*** BOVINE SPONGIFORM ENCEPHALOPATHY BSE TSE PRION SURVEILLANCE, TESTING,
AND SRM REMOVAL UNITED STATE OF AMERICA UPDATE JULY 2016
Tuesday, July 26, 2016
*** Atypical Bovine Spongiform Encephalopathy BSE TSE Prion UPDATE JULY
2016
Saturday, July 16, 2016
*** Importation of Sheep, Goats, and Certain Other Ruminants [Docket No.
APHIS-2009-0095]RIN 0579-AD10
WITH great disgust and concern, I report to you that the OIE, USDA, APHIS,
are working to further legalize the trading of Transmissible Spongiform
Encephalopathy TSE Pion disease around the globe.
THIS is absolutely insane. it’s USDA INC.
http://scrapie-usa.blogspot.com/2016/07/importation-of-sheep-goats-and-certain.html
Monday, June 20, 2016
*** Specified Risk Materials SRMs BSE TSE Prion Program ***
Thursday, October 22, 2015
*** Former Ag Secretary Ann Veneman talks women in agriculture and we talk
mad cow disease USDA and what really happened those mad cows in Texas ***
*** 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...
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.
terry
posted by Terry S. Singeltary Sr. | 3:01 PM
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