Subject: Case-control study on the use of pituitary-derived hormones from sheep as a potential risk factor for the occurrence of atypical scrapie in Great Britain
Paper
Case-control study on the use of pituitary-derived hormones from sheep as a potential risk factor for the occurrence of atypical scrapie in Great Britain
E. Marier, BSc, MBA1, M. Dawson, DVM, MSc2, M. Simmons, DVM, PhD3, J. Hope, BSc, PhD2 and A. Ortiz-Peláez, DVM, PhD1 Author affiliations
Abstract A case-control study was conducted in 2013 to investigate the use of pituitary-derived hormones from sheep as a potential risk factor for the presence of atypical scrapie in Great Britain sheep holdings. One hundred and sixty-five holdings were identified as cases. Two equal sets of controls were selected: no case of scrapie and cases of classical scrapie. A total of 495 holdings were selected for the questionnaire survey, 201 responses were received and 190 (38.3 per cent) were suitable for analysis. The variables ‘use-of-heat-synchronisation/superovulation’ and ‘flock size’ were significantly associated with the occurrence of atypical scrapie. Farms with atypical cases were less likely (OR 0.25, 95 per cent CI 0.07 to 0.89) to implement heat synchronisation/superovulation in the flock than the control group. Atypical cases were 3.3 times (95 per cent CI 1.38 to 8.13) more likely to occur in large holdings (>879 sheep) than in small flocks (<164 a="" and="" association="" atypical="" between="" case-control="" case="" consistent="" div="" drugs="" factor="" flock="" for="" generic="" having="" hormones="" hypothesis="" if="" initial="" is="" nbsp="" negative="" occurrence="" of="" out="" pituitary-derived="" practices="" previous="" proxy="" risk="" rules="" scrapie.="" scrapie="" sheep="" significant="" size="" study.="" superovulation="" that="" the="" these="" use-of-heat-synchronisation="" use="" using="" was="" with="">
(It was noted with concern that hormone extracts could be manufactured by a veterinary surgeon for administration to animals under his care without any Medicines Act Control.)
PITUITARY EXTRACT
This was used to help cows super ovulate. This tissue was considered to be of greatest risk of containing BSE and consequently transmitting the disease.
BEEF BRAIN AND BRAIN INFUSION BROTHS
Considered to be of great risk.
COMMERCIAL IN CONFIDENCE
MEDICINES ACT - VETERINARY PRODUCTS COMMITTEE
5 BLANK PAGES. ...TSS
7. Any Other Business
TWA LITTLE STATEMENT 331
8 June 1988 Internal CVL meeting to discuss the implications of BSE to Biologicals Products containing bovine extracted material (Annex 6). (YB 88/06.08/11.1-11.2) Following a detailed review of situation the following recommendations were made:
1. Specific concern over use of pituitary gland products by veterinary surgeons and companies. Paper to be produced for Tolworth (Veterinary Medicines Division).
2. Urgent review of all products both immunological and pharmaceutical for possible inclusion of ingredients of bovine origin.
3. Draft guidelines to be presented in full to the National Office of Animal Health (NOAH), the trade body representing the Veterinary Medicines part of the pharmaceutical industry, at next meeting on 11 July 1988
TWA LITTLE minute
2. We have identified one problem over where we are unable to act and this is the use of gonadotrophins in embryo transfer work. Some veterinary surgeons are quite legally using this exemption from the Medicines Act contained in Section 9(2) to prepare gonadotrophins from pituitary glands from various species, including cattle. These hormones are used to stimulate superovulation in donor cows.
COMMERCIAL IN CONFIDENCE
3.2 Minute 5.3 - 5.4 Bovine Spongiform Encephalopathy
It was reported that some replies had been received from Companies using pituitary glands in their products. Copies of the BSE document had also been sent to DHSS and NIBSC.
and then another 3 + pages of blank space. ...TSS
COMMERCIAL IN CONFIDENCE
BSE - CURRENT POSITION WITH VETERINARY LICENCED PRODUCTS (MA.1968)
There are three areas of particular concern, vaccines (including emergency vaccines), pharmaceuticals which are covered by MA licences and unlicenses hormonal products produced under exemptions claimed under (Section 9(2) Medicines Act).
1) Vaccines
NOT FOR PUBLICATION
another 6 pages of blank space. ...TSS
COMMERCIAL IN CONFIDENCE
COMMERCIAL IN CONFIDENCE
Medicines Act - Veterinary Products Committee
COMMERCIAL IN CONFIDENCE
MANAGEMENT IN CONFIDENCE
CERTIFIED BSE-FREE HERDS FOR SOURCE OF MATERIAL FOR BIOLOGICAL PRODUCTS
snip...see more here ;
3. The extraction is from a pool of pituitary glands collected from abbatoirs and the process used is unlikely to have any effect on the BSE agent. Hormones extracted from human pituitary glands have been responsible for a small number of Creutzfeldt Jacob disease in man.
SEE LOOPHOLE ;
SEE LOOPHOLE SHOULD BE CLOSED ;
Subject:
bovine pituitary started bse epidemic?
From:
tom
Reply-To:
Bovine Spongiform Encephalopathy
Date:
Mon, 9 Aug 1999 22:24:22 -0800
Content-Type:
multipart/alternative
Parts/Attachments:
Parts/Attachments text/plain (269 lines) , text/enriched (371 lines)
Reply Reply
The London Observer ran an interesting story on a BSE origin theory involving widespread use of bovine pituitary extracts used to induce multiple ovulations, higher milk production, and so forth.
This same theory has come up in the case of the1985 Stetsonville outbreak in Wisconsin. Apparently the US was also using pituitary derived growth hormone to boost production in dairy cattle. It is hard to get a handle on how widespread this practise was.
The Inquiry made a very good effort indeed but there are still a lot of questions outstanding.
tom
"A cottage industry appears to have existed where middlemen bought materials such as pituitary glands from abattoirs. The hormone was extracted crudely using ordinary food blenders and sold to farmers and vets. Wheatley claims slaughtermen at her local abattoirs have admitted selling pituitary gland to vets and researchers. She says one is preparing to make a statement to an ongoing BSE inquiry chaired by Lord Phillips.
Startling new evidence has already emerged at the inquiry that top government vets believed this practice was going on. A minute of 10 June 1988 reveals that Dr Tony Little, the senior director of the Government's Centre of Veterinary Laboratories, knew that vets were using pituitary extracts from slaughtered cattle. He believed, though, that there was nothing the Government could do to stop 'the use of uncontrolled bovine pituitary extract'. Last month the BSE inquiry quizzed Dr Little on the possibility of pituitary hormones causing the spread of BSE. He admitted: 'It was discussed.'
<< XXXXX DRUDGE REPORT XXXXX SUNDAY, AUGUST 08, 1999 1:20:41 ET XXXXX
ATTEMPTS TO CREATE 'SUPER CATTLE' MAY HAVE LEAD TO MAD COW DISEASE
THE OBSERVER, the London daily newspaper, is reporting on Monday that the "mad cow" epidemic may have been caused by scientific attempts in the 1980s to create a super cow.
Reporters Patrick Wintour and Antony Barnett cite experts who "believe that hormones, taken from the brains of slaughterhouse carcasses, were injected into cows in a bid to create a new breed of super-cattle."
"The hormones, extracted from pituitary glands, were transmitted in an agent that spread mad cow disease and eventually infected humans as new variant Creutzfeldt-Jakob Disease (nvCJD)."
The article describes how the use of human growth hormones in the past has created scientific nightmares as results:
"Twenty years ago, a similar use of human growth hormone, extracted from the pituitary glands of cadavers and given to children with congenital dwarfism, was shown to have spread CJD among humans."
While many scientists and cattle experts believe the theory to be compelling, a spokesman for the British Ministry of Agriculture told the paper, "It is a theory being considered, but it is only a theory."
So far, the disease has killed 43 people, and cost Britain upwards of $6.4 billion pounds ($9.7 billion USD).
How madness took hold
Was the treatment used to stimulate children's growth, help infertile women and breed super-cattle to blame for CJD deaths and the beef crisis? Antony Barnett investigates
Sunday August 8, 1999
It was September 1985 and 22-year old Alison Ley was returning home from hospital. She could barely move and had severe difficulty speaking. Summoning up all her strength, Alison turned to her mother Mavis and told her she wanted to die. She never said another word and died three months later.
Alison's slow and painful death was later diagnosed as Creutzfeldt-Jakob disease.
As a child Alison had hardly grown and was found to suffer from a pituitary gland disorder. She had longed for the chance to grow to a normal height. In the 1970s it appeared a miracle cure was at hand, and Alison and thousands of other children with a condition similar to hers were treated with growth hormone. But as she moved into her twenties she became desperately ill.
The same month that Alison told her mother she no longer wanted to live, Carole Richardson, a senior scientist at the Ministry of Agriculture's veterinary laboratories in Surrey, was busy examining the brain tissue of a cow that had died on a Sussex farm after exhibiting mysterious symptoms. The animal had suffered head tremors, disorientation and weight loss. Cow 133, as she became known, has now gone down in history as the first animal to have been officially diagnosed with Bovine Spongiform Encephalopathy.
These two events in September 1985 have never before been publicly linked.
But an Observer investigation has uncovered evidence that not only were they related, but that the link might provide the answer to why Britain was hit by a BSE epidemic that nearly destroyed its beef industry and might still ultimately kill millions.
Incredibly, there are still many unanswered questions about the source of the 'mad cow' disaster that so far has cost the country £4 billion.
It was long believed that cows became infected by eating food that included the remains of sheep suffering from scrapie. But this theory has now been discredited by some leading BSE specialists.
The most popular explanation emerging has become known as the 'one old cow theory'. This argues that isolated and extremely rare cases of BSE had always occurred sporadically, and unrecognised, in the cattle population in Britain.
Somehow, somewhere, a cow with BSE got recycled - probably through meat and bonemeal from slaughtered cows being fed back through cattle feed.
When the BSE epidemic broke in the 1980s, the disease was found in pockets all over the UK. But because many farmers at the time got their cattle feed locally, experts suggest another factor must have been responsible for its spread. Something new must have sparked the epidemic. But what?
Alison Ley's tragic death in 1985 - and those of the 31 other children who have died in similar circumstances since - might now offer the answer.
Unlike dwarfism, which is a chromosomal disorder, Alison's condition was caused by malfunctioning hormones. The breakthrough in the 1970s was to discover that Alison and children like her could be helped by growth hormone injections three times a week.
These hormones had been taken from pituitary glands - part of the brain - extracted from human corpses. The year Alison died, it emerged that three children who had been receiving growth hormone injections in the US had also died of CJD.
It was clear something was going fatally wrong and the Department of Health was forced to abandon the injections. Now such growth hormones are synthetically made, but last year the Government was forced to pay large amounts in compensation and admit a cover-up of astronomical proportions.
It emerged that as early as 1976 the Department of Health had been warned of the risk of humans contracting CJD from pituitary hormones.
They were not only being used to help children suffering from stunted growth either. At the same time, scientists had discovered that another pituitary hormone, known as gonadotrophin, helped stimulate the ovaries of women who could not produce eggs. Injecting women with the hormone increased the chance of pregnancy and this became an early treatment for infertility.
But yet again disaster struck. Four women in Australia using the treatment died of CJD. Like growth hormones, the gonadotrophins were extracted from the pituitary glands of human corpses. Once again the practice was halted, and the Australian government paid compensation to the victims' families after evidence emerged that officials knew that CJD could be transmitted through brain tissue.
Indeed the American scientist who proved it, Professor Daniel Gajdusek, won a Nobel Prize in 1976 for his work, so the international medical and scientific community could hardly have overlooked the risks.
So could it be just coincidence that humans treated with pituitary hormones started contracting CJD at the same time British cattle began dying of mad cow disease? Could it just be coincidence that BSE was later linked to a new variation of CJD in humans that has so far killed 43 people? Dr Anne Maddocks, a retired senior medical scientist, does not think so. Neither does Joanna Wheatley, a former ICI researcher and now an organic beef farmer in Berkshire. Both have given evidence to the Government's BSE inquiry suggesting something more sinister was at work than just chance.
More significantly, Professor Malcolm Ferguson-Smith, an award-winning Cambridge University geneticist on the Government's BSE inquiry team believes there are serious questions to answer about the use of pituitary hormones.
The fact is that, just as the medical establishment was experimenting with these types of hormones in humans, veterinary scientists and drug companies were becoming excited about their potential use in cattle. The view was that these hormones could increase milk yields, enhance reproduction and boost farmers' profits.
In Britain, scientists at the Animal Research Council at Cambridge University were particularly intrigued at the possibility of producing a super-breed of cows using a technique called multiple ovulation embryonic transfer, or MOET for short.
The idea was that, by injecting pituitary hormones into cows, the animals would produce several eggs instead of a single one as they would naturally. Such a method was of particular value to farmers if they had a cow with a high-quality genetic make-up, for instance, a cow that produced large quantities of milk.
By forcing this cow to produce several eggs, the fertilised embryos could be transferred to cows who would then all give birth to super-calves.
Hormones are still widely used in farming, but most are now made in a laboratory rather than taken from carcasses. But in the early days hormones were extracted from glands taken from dead animals. Maddocks is a former clinical microbiologist who specialised in infection control at St Mary's Hospital in London. She has spent a year investigating the use of pituitary hormones in cattle and links to CJD in humans.
'The theory is simple,' she says. 'The promiscuous use of pituitary hormones in cows may have resulted in BSE in the same way that pituitary treatment in humans caused deaths by CJD.
'The timing of the deaths in the cattle and human population who were exposed to pituitary hormones seems highly compelling.'
Maddocks stresses that it is not the hormones themselves that transmitted BSE, but the extracts of the pituitary gland which might have contained bits of contaminated brain tissue and spread the disease nationwide.
During the 1980s a handful of reputable companies specialised in pituitary hormone treatment for cattle, but these are unlikely to have taken any risks with the hormones they used. Most deny they used any bovine material.
Nonetheless, a cottage industry appears to have existed where middlemen bought materials such as pituitary glands from abattoirs. The hormone was extracted crudely using ordinary food blenders and sold to farmers and vets.
Wheatley claims slaughtermen at her local abattoirs have admitted selling pituitary gland to vets and researchers. She says one is preparing to make a statement to an ongoing BSE inquiry chaired by Lord Phillips.
Startling new evidence has already emerged at the inquiry that top government vets believed this practice was going on. A minute of 10 June 1988 reveals that Dr Tony Little, the senior director of the Government's Centre of Veterinary Laboratories, knew that vets were using pituitary extracts from slaughtered cattle.
He believed, though, that there was nothing the Government could do to stop 'the use of uncontrolled bovine pituitary extract'. Last month the BSE inquiry quizzed Dr Little on the possibility of pituitary hormones causing the spread of BSE. He admitted: 'It was discussed.
'There were problems with the legislation, which is why they were unlicensed, and why veterinary surgeons could carry out this technique.
'We did write to a number of people and we did put a letter in the Veterinary Record to warn people that, although there was no legislation which enabled us to control it, we considered it an unwise practice.'
The Government's inquiry into the BSE epidemic is doing its best to leave no stone unturned, but former Ministers and civil servants are anxious that the blame does not lie at their doors.
Guardian Unlimited © Guardian Newspapers Limited 1999
======
Subject:
The Possible relationshipt between BSE and use of pituitary hormones in cows...
From:
"Terry S. Singeltary Sr." <flounder@wt.net>
Reply-To:
Bovine Spongiform Encephalopathy
Date:
Fri, 11 Feb 2000 14:55:19 -0600
Content-Type:
text/plain
Parts/Attachments:
Parts/Attachments text/plain (336 lines)
Reply Reply
######### Bovine Spongiform Encephalopathy #########
Greetings list members,
I find this article most interesting. Might be old news to some, but thought some might find it as interesing as I did........
Kind Regards, Terry S. Singeltary Sr., Bacliff, Texas USA
___________________________________________________________________
Dr Anne Maddocks 16/06/99
THE BSE INQUIRY
Statement of Dr Anne C Maddocks M.A, B.M, B.Ch, F.R.C.Path
The possible relationship between BSE and use of pituitary hormones in cows
1. Introduction
1.1 It is suggested in this statement that the promiscuous use of pituitary hormones in cows may have resulted in BSE in the same way that treatment with pituitary growth hormone (hGH) or follicular stimulating hormone (FSH) has been shown to cause iatrogenic CJD in humans.
1.2 The important difference between the medical and veterinary use of these hormones being that slaughtered cattle subsequently entered the animal food chain as meat and bone meal (MBM) creating the likelihood of a widespread dispersal of any infectivity able to survive the rendering process.
1.3 The use of hormones in cows has a very complex background which is little known among ordinary farmers. Although 'published' the material from which the findings in this paper have been drawn was only available via several visits to the library at Wye College (University of London Department of Agriculture), The Scientific Periodicals Library at Cambridge, The Royal Society Library, The Royal Society of Medicine's Library, The British Library at St. Pancras, British Library Science Collections at Holborn and extensive use of the Aldwych branch of the British Library Science Collections and their stock from Boston Spa. (This search was part of wide BSE studies which do not relate to the Inquiry).
1.4 This extensive trawl was necessary to locate both the original experimental work and reports of cattle breeders' conferences reflecting the later practical application of that work because there is little direct publication of findings and outcomes by the commercial cattle breeding sector in the UK. (The journal "Theriogenology" has contributions from US commercial Embryo Transfer (ET) workers). Whilst the underlying science is abstruse and reported only haphazardly it should be noted however the 'ordinary farmers' do use the M.O.E.T. system (see Appendix Five to this statement) to breed from their best cows. This may involve an ET centre or may be done on the farm.
1.5 The background to this area lies in the science of Endocrinology which is applied in both Medicine as therapy, and Agriculture as manipulatory techniques to increase milk yield and enhance production. This is the reason for the wide spectrum of ultra specialist journals which has to be consulted and whose normal readership will consist _________________________________________________________________
only of the most scientific of obstetricians, agribusiness or breeding specialists, none of whom would be likely to read right across the spectrums' medical and veterinary aspects.
1.6 I should like to point out that professionally, while I do not belong to those groups, I am a very experienced control of infection specialist, as well as a clinical microbiologist. It is professional suicide for infection control doctors to accept as 'mere' coincidences similar events which are close in space or time. It must be assumed that in depth investigation may reveal links or common factors, and it is necessary to 'hack in' to specialist areas through research. This is my position in this instance.
1.7 Please note for clarity this account is written without the historical background and most of the scientific detail - important though these are to the argument. It has been thought better to put this detail into Appendices at the end of the document where they can be separately considered, rather than have one very detailed and lengthy account.
2. The argument for the transmission of a TSE which became the BSE outbreak through use of cadaveric hormones
2.1 Transmissible Spongiform Encephalopathies (TSEs) are rare diseases. Since Kuru was described in 1957 only familial variants have been found but suddenly in 1985 two previously unknown TSEs emerged at once, a striking coincidence that merits attention.
2.2 The possible significance of BSE and hormone related CJD occurring at about the same time has been obscured because:
(a) neither disease was publicised for some time and then when they were publicised it was through articles which appeared in different sub-speciality journals.
(b) hormone therapy related CJD (so far as it was discussed at all) was seen as obviously an iatrogenic disease with a known origin. BSE on the other hand was portrayed as a "mystery disease" which baffled scientists.
2.3 An in depth look at historical events gives a different perspective on these two diseases and a possible reason why they appeared at the same time.
2.4 The most important point to have in mind when reflecting on this coincidence is that advances made in endocrinology are applied in both medicine and veterinary science. Endocrinology is a "free-standing" science rooted in physiology, with its own specialist departments and techniques drawing on animal experiments, endocrine biochemistry and electron microscopical ultra structure studies. As advances are made in endocrinology they are fed across into both medicine and agriculture at about the same time like a rising tide advancing on all fronts.
2.5 Given that the human disease is undoubtedly related to pituitary hormone therapy, is there any possibility of a similar pituitary hormone relationship with BSE? ________________________________________________________________
2.6 We know that use of pituitary hormones in the 1970s and 1980s resulted in deaths from CJD throughout the world but most notably in the UK, France, USA and Australia. Thinking about BSE has focussed (understandably) upon the way in which the original isolated cases of the diseases were magnified into an epidemic, less attention has been paid to the reasons for its original emergence in different places but at the same time. If it could be shown that cows had been given pituitary hormones, then it would seem reasonable to look to see if:
(a) these might have been contaminated and
(b) whether this could have been responsible for the transmission of a previously unknown TSE amongst cows.
3. Hormones
A. Human pituitary growth hormone (hGH) and Human pituitary fertility hormones
3.1 Human pituitary growth hormone (hGH) and Human pituitary fertility hormones had been used in treating humans, as replacement therapy and both types definitely gave rise to CJD cases (see hGH/CJD legal case reports - Morland Papers (M2 Tab 1) -and Allars Report) (M1 Tab 1).
B. Cows
3.2 Improvement in "production" was a constant ambition for agriculturists in all possible ways. Embryo transfer however was in a class of its own; it was a sort of "Grail Quest" with its origins in the 1890s (Heape at Cambridge) and with a long history of hard struggle 1949 to 1970s with a considerable emotional investment and commitment at the Unit for Animal Reproduction (UAR) at Cambridge University.
3.3 Bovine pituitary growth hormone (bGH) was given to boost milk yield and pituitary fertility hormones fi'om various species were given to cows as one of the methods of stimulating Multi-Ovulation for Embryo Transfer (the M.O.E.T. System - see Appendix Five) in order to manipulate normal reproductive functions.
3.4 As it happened the hormone used at the UAR was non-pituitary so no problems could emerge. It was only with the promiscuous use of various pituitary gonadotrophins in the 1970s that the door would have been open for prion type agents to be transmitted. Whilst growth hormones are species specific, Follicular Stimulating Hormone (FSH) from cows, horses, pigs and sheep were capable of being used with success in the M.O.E.T. process; as this method moved out of the research environment at Cambridge (having been publicised at various cattle breeders meetings) and became a mechanism of agricultural production, whatever hormones were available were used. It is in this promiscuity of use that the possibility of TSE transmission arises.
C. Luteinising Hormone (LH)
3.5 Since writing the above I have been told that pituitary luteinising hormone (LH) also was used more frequently than I had realised to prepare recipient cows, ie on a larger number of cows than were donors. As this was also a pituitary hormone it represents yet another possible path. _____________________________________________________________
MIRROR IMAGES [NA...TSS] sporadic CJD cases ? sporadic BSE ____________________________________________________________
3.6 This demonstrates potential routes of spread for bovine infections which run in parallel with human iatrogenic disease.
3.7 Because we know that pituitary derived hormones are a potentially highly successful means of infection the use of pituitary derived gonadotrophin to stimulate multi ovulation in M.O.E.T techniques appears to be a likely candidate route for spread of the disease (this applies particularly if "cottage industry" bovine hormones are used).
3.8 As to timing, human hGH and hFSH treatments were finally fully developed in the - 6 -1970s. Indeed, the majority of the iatrogenic CJD victims received their treatment then. M.O.E.T for cows also burgeoned in the late 1970s.
3.9 That two new diseases both appeared in one year (1985) really is fortuitous because of the different incubation periods and amplification by MBM in feed but even two similar new diseases appearing within a year or two would be significant.
3.10 My thesis is that:-
(i) Although only a relatively small number of animals might be infected at first by pituitary hormones, acting as a "starter" event, this would of course be hugely amplified by "cow cannibalism" - Meat and Bone meal in feed (see Mirror Images diagram).
(ii) A suspect batch of hormone might be used in several different geographical areas giving rise ultimately to more or less simultaneous, dispersed outbreaks, which would all of course be of a similar type.
(iii) These outbreaks could act as a "platform" for the take-off of the epidemic.
(iv) Choice of pituitary Hormones. (see Appendix Four: Gonadotrophins)
3.11 It must be remembered that the problem arises not from the hormonal action as such, but because the pituitary is effectively part of the brain and can contain TSE agents. As might be expected problems only occurred (in growth hormone and fertility treatment) where the chosen hormone was extracted from the pituitary.
3.12 Human fertility treatment with menopausal urine gonadotrophin was used in Europe without problems, only the Australians using pituitary FSH had CJD cases. In the same way Cambridge M.O.E.T research in the 1950s and 1960's used PMSG (pregnant mare serum gonadotrophin) without problems. A TSE could only appear when pituitary FSH was used instead, most likely when the technique was applied in the field in the 1970's. The change back to pituitary hormone was probably due to its greater commercial availability in the USA and possibly its action in crude extracts. (PMSG activity was not easy to control and also repeat cycles lead to antibody production).
3.13 It has to be pointed out that there is a missing factor in this hypothesis which is a sporadic form of BSE in cows comparable to sporadic CJD in humans. Such a condition is innately likely to exist however (on the basis of the similarity of ________________________________________________________________
mammalian prion proteins) and is accepted as the basis of the "one old cow" theory of BSE origin - of which the hormone-use theory is a variant.
4. A new event- why should BSE happen in 1985
4.1 The injection of pituitary hormones is the "new thing" that happened not feeding meat and bone meal which had occurred for many years (although of course feeding meat and bone meal was "cannibalism" and was recognised (too late) as a potential route tbr recycling infections). Once the infection was established, the MBM recycling effect would have been a powerful route of infection.
4.2 Although any pituitary hormone could carry a TSE it seems most likely that Embryo Transfer in the 1970's, particularly the rush to commercial non-surgical transfer in the late 1970's was the potential advent. A wide variety of hormones (probably including bovine FSH) was used, but semi-commercial E.T. was not documented or controlled so we will never know what was used in all instances (see Appendix Five on M.O.E.T).
5. Conclusion
5.1 It seems at least possible that in the same way that well-intentioned growth hormone replacement therapy and fertility treatment with FSH led to CJD cases, the BSE outbreak was a tragic outcome of an heroic effort (1890-1970s) to bring about bovine embryo transfer.
5.2 This would not have happened had everyone continued to use the non-pituitary gonadotrophin (PMSG) used in the original research at Cambridge, but the potential transmission risks of pituitary extracts were only begun to be understood in the mid 1970s as instances of iatrogenic transmission were reported and validated. (bGH for extra milk yield remains another possible origin, but the timing displayed favours the FSH hypothesis).
5.3 This hypothesis is not provable but the timing appears compelling.
5.4 In the following appendices, I develop more specific aspects of this argument and detail my sources for this submission. _______________________________________________________________
References
"The History of Clinical Endocrinology" by V C Medvai (1993) "Controlled Reproduction in Cattle and Bufib. lo" by Ian Gordon (1996)
############ http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############
Subject:
Vaccines Annex 1, 2, and 3
From:
"Terry S. Singeltary Sr." <flounder@wt.net>
Reply-To:
Bovine Spongiform Encephalopathy
Date:
Mon, 21 Aug 2000 10:54:16 -0700
Content-Type:
text/plain
Parts/Attachments:
Parts/Attachments text/plain (648 lines)
Reply Reply
######### Bovine Spongiform Encephalopathy #########
Greetings List Members,
i will start posting old documents about the concerns about vaccines and biological products, some of which i may have passed before. please be patient. i will try and start from the beginning and work up to the latest documents. hope some of you find interest in these documents.
with kind regards, Terry S. Singeltary Sr., Bacliff, Texas USA ===========================================
ANNEX 1 (VACCINES) Ministry of Agriculture, Fisheries and Food Research and Services Central Veterinary Laboratories and Veterinary Investigation Centres 86/00.00/1.1 ==============
RETURN TO VETERINARY LABORATORY NEW HAW, WEYBRIDGE, SURREY. MINISTRY OF AGRICULTURE FISHERIES AND FOOD
RESEARCH AND SERVICES
CENTRAL VETERINARY LABORATORIES and VETERINARY INVESTIGATION CENTRES
1986
86/00.00/1.2 =============
CENTRAL VETERINARY LABORATORY
New Haw, Weybridge, Surrey, KT15 3NB Telephone 093 23 (Byfleet) 41111 Telex 262318 VETWAY G
Director of Veterinary Laboratories
AJ Stevens, MA, BVSc, MRCVS, DipBact
Deputy Directors
WJ Brinley Morgan, DSc, PhD, BVSc, MRCVS, DipBact WA Watson, PhD, BVSc, FRCVS
CATTLE BREEDING CENTRE Shinfield, Reading, Berks RG2 9BZ Telephone 0734 883157
Head of Centre PH Lamont, PhD, BSc, MRCVS
LASSWADE VETERINARY LABORATORY
Bush Estate, Penicuick, Edinburgh Telephone 031 445 4811
Head of Laboratory AR Hunter, BVMS, MRCVS, DipAH
Laboratory Secretary NLD Brown Training officer and Visitors DH Evans FIMLS, MIBiol Chief Technical Officer DW Andrews Safety Officer D Sweasey Librarian Mrs DC Scott, BA, ALA
VETERINARY INVESTIGATION SERVICE
BM Williams, MRCVS, DVSM
Animal Ilealth Division, Hook Rise South, Tolworth Surbiton, Surrey KT6 7NF Telephone Ol 337 6611 Telex 22203 AHSURB G
86/00.00/1.3 ============
MEDICINES UNIT
Head of Unit ARM Kidd, MSc, BVSc, MRCVS
RS Cameron, BSc, MRCVS AK Gray, MSc, BVetMed, EG Hartley, MRCVS, MIBiol EEB Watson, BVMS, MRCVS
Maureen JE Millar, BA(Hons), MPS, DipInfoSci JP 0'Brien, BPharm, MPS Mrs AD Hardisty, MPS
AW Edgar, BA Kristina Feesey, MSc, CBiol. MIBiol JB Whitehead
Caroline Evans GC Evans, CBiol, MIBiol MA Peirce, PhD, FIBiol, CBiol
Statutory Functions
The Medicines Unit provides guidance to the pharmaceutical industry on the preparation and submission of applications for all types of Veterinary Product Licences and Animal Test Certificates issued under the Medicines Act 1968. Applications accompanied by data on safety, quality and efficacy are then assessed by veterinary, pharmacy and scientific staff in preparation for consideration by the independent Veterinary Products Committee.
Several EEC Directives also impinge directly on the statutory work carried out by the Medicines Unit, in particular, directives dealing with the standards and procedures required for marketing veterinary pharmaceutical medicines, the directive concerned with feed additives and the directive concerned with hormones.
The Medicines Unit also promotes the collection and investigation of information relating to adverse reactions, and ensures that the appropriate action is taken.
86/00.00/1.4 ============= BIOLOGICAL PRODUCTS AND STANDARDS DEPARTMENT Head of Department I Davidson, BSc, MRCVS
viral products Control Section Denise H Thornton, PhD, BSc PR Luff, BSc, BVetMed, MRCVS J0S Watson, BVSc, MRCVS IG 1lopkins, FIMLS KR Edwards RAJ Nicholas, MSc, MIBiol
Baterial products Control Section Aileen MT Lee, phD, BVSc, MRCVS SN Hussaini, PhD, BVSc, MRCVS VJ White, AIMLS
Production Section JC Muskett (Senior Technical Officer) AD Maley, AIMLS AJ Taylor, LiBiol
Medicines Act Inspector KJ MacOwan, phD, BVMS, MRCVS
Research Activities
Avian encephalomyelitis vaccines (IO Hopkins, RAJ Nicholas) Improved methods for virus content and potency tests
Avian reouipus infection (DH Thornton, GW Wood) Development of a potency test for viral arthritis vaccine Examination of cross protection between different serotypes
Bacteriades nedosus vaccines (WJ White) Development of reagents and tests for antigen quality
Bovine viral diarrhoea and border disease vaccines (DH Thornton, JOS Watson, IG Hopkins) Evaluation and standardization of methods for virus titration Investigation of genetic stability
Bracelia abortus antigen (JC Muskctt, AD Maley) Experimental and developmental work on the cultivation of antigen strains by continuous culture
Btucella abortus vaccine (IG Hopkins) Development of an international standard
Canine and feline vaccines (DH Thornton, PR Luff, KR Edwards) Investigation of rectifications for virus content, potency, safety and stability of live vaccines Antigen content of inactivated vaccines Serological response in ]aboratory animals
86/00.00/1.5 =============
Clostridial products (AMT Lee, VJ White) Development of the potency test for Clostrldiwn ehauvoai vaccines Development of a standard for Cl. haemolyticum vaccines Development of alternatives to challenge tests In animals as tests of potency Production of clostridial toxins and their evaluation as reagents for testing clostridial vaccines and sera Screening tests for potency of clostridial products
Duck virus hepatitis vaccine (PR Luff, IG Hopkins) Development of a potency test and evaluation of serological tests
Egg drop syndrome 76 vaccines (PR Luff, I6 Hopkins) Development of a potency test
Escherichia coli vaccines (SN Hussaini, AW Edgar) Identification and quantification of antigenic components of oral and parenteral vaccines Detection and measurement of endotoxin
Infectious bovine rhinotracheitis vaccines (ZOS Watson, fG Hopkins) Assessment of safety and efficacy of Jive and inactivated IBR vaccines Comparison of methods to determine humoral antibody response to IBR infection Preparation of standard IBR antiserum for serological tests
Infectious bronchitis vaccine (IG Hopkins) Evaluation of the safety of live vaccines Development of potency tests for live and killed vaccines
Infectious bursal disease vaccine (DH Thornton) Development of tests for safety and potency
Johne'e disease (AMT Lee) Improvement of specificity of johnin test
Leptospirosis vaccines (IG Hopkins) Studies on immunological response of calves and laboratory animals to L. hardjo vaccine Development of a potency test for L. hardjo vaccine
Mallein (AMT Lee) Development of an international standard for mallein PPD
Parainfluenza 3 vaccines (DH Thornton) Investigation of quality control methods
Porcine parvovirus vaccines (DH Thornton, PR Luff, KR Edwards) Development of safety and potency tests
Preservatives in biological products (IG Hopkins) Development of methods for detection and quantification of antibiotics and chemical preservatives in biological products
Respiratory syncytial virus vaccines (D. H. Thornton) Investigation of quality control methods
86/00.00/1.6 ============
Salmonella vaccines (SN Hussaini, AW Edgar) Development of potency test for living vaccines
Sterility testing of biological substances (IG Hopkins) Studies on methods for testing biological substances for freedom from bacterial, fungal and mycoplasmal contamination. Preparation of reference strains of organisms
Tuberculins (AJ Taylor, JC Muskett, A.M.T. Lee) Development of production techniques Development of an international standard for PPD of bovine tuberculin Assay methods
Viral vaccines in general (DH Thornton, JOS Watson PR Luff, fG Hopkins, RAJ Nicholas, GW Wood, KR Edwards) Development of purified antigens and monospecific antisera for use in serological tests for detection of viral contaminants Development, evaluation and standardisation of methods for detecting viral contaminants in vaccines and supply flocks Methods for testing adjuvanted vaccines Investigation of adverse reactions Molecular examination of vaccine strains Preparation of monoclonal antibodies for use as standards and reagents
Services
International Standards (AMT Lee, DH Thornton and staff) FAO/WHO International Laboratory for Biological Standards, responsible for the development, production, custody and distribution of veterinary international standards, reference preparations and reference reagents and for drawing up international requirements for veterinary biological products
Reagent production (DH Thomton and staff) For diagnosis and monitoring of SPF flocks
Tuberculin production (JC Muskerr and staff) PPD of avian and bovine tuberculins and of johnin, primarily for use by the Ministry
Vaccine, antigen and media production (JC Muskett and staff) Johne's disease vaccine Br. abortus Strain 99 antigen for the Ministry's brucellosis eradication programme Pullorum disease antigen for the Ministry's Poultry Health Scheme Mallein Media production, sterilisation and glassware-washing service to the Central Veterinary laboratory, the Veterinary Investigation Service and the Veterinary Field Service
Statutory Functions
Medicines Act (AMT Lee, DH Thornton, KJ MacOwan and staff) Examination of, and advice on, applications submitted under the Medicines Act and the Therapeutic Substances Order for licences to
86/00.00/1.7 =============
market veterinary immunological products (in conjunctfon with the Medicines Unit) Testing of samples of such products for mafety, efficacy and quality, the scrutiny of manufacturers' test protocols and the development and evaluation of test methods Providing British standards for use in quality control tests Inspection of the manufacture of veterinary immunological products
86/00.00/1.8 =============== MINISTRY OF AGRICULTURE FISHERIES AND FOOD HOOK RISE SOUTH TOLWORTH SURBITON SURREY KT6 7NF TELEPHONE 01-337 6611 Ext 525
Mr R Hancock VI Centre TRURO
13 May 1987
Dear Roger,
LETTER TO VETERINARY RECORD 'A CASE OF SPONIFORM ENCEPHALOPATHY IN THE BOVINE'
Further to our telephone Conversation this morning, I am now confirming that the letter to the Veterinary Record which cleared earlier in the week should not be published. I explained to you that this condition had been discussed by the CV0 and the Director of CVL, and because of possible effects on exports and the political implications it had been decided that, at this stage, no account should be published. No doubt there will be an opportunity for your case to be published in due course.
Yours sincerely B M WILLIAMS Assistant Chief Veterinary officer
cc: Dr Watson Mr Pill
[recieved 18, May 1987 Pathology Department]
87/05.13/1.1 ============= ANNEX 2
COMMERCIAL IN CONFIDENCE
MEDICINES ACT - VETERINARY PRODUCTS COMMITTEE
Minutes of the Biologicals Committee meeting held on Wednesday 6 January 1988, at 10.00am in the Old Library. Central Veterinary Laboratory, Weybridge.
Dr Little - Chairman
Mr Basham Dr Lee Mr Beusfield Mr Luff Dr Bracewell Dr MacOwan Mr Gray Dr Thornton Mr Harkness Mr Treves - Brown Dr Hussaini Mr Whitehead Dr Lamont Mr Wood
Mrs Evans - Technical Secretary
88/01.06/1.1 ===============
B L A N K P A G E
88/01.06/1.2 ===============
B L A N K P A G E
88/01.06/1.3 ===============
HALF OF PAGE B L A N K
8.2 Bovine Spongiform Encephalopathy
1) A draft paper from BP&S entitled 'Bovine Spongiform Encephalopathy implications for biological products' was tabled.
2) After a brief discussion it was agreed that an amended paper should be distributed to all members for discussion at the next Biologicals meeting.
9. Date of the Next Meeting
9.1 The next meeting will be on Wednesday, 3 February 1988 in the Old Library.
January 1988
MEDICINES UNIT CVL, WEYBRIDGE
88/01.06/1.4 =============
Synthesised hormones.
Biological Products and Standards Department Central Veterinary Laboratory New Haw, Weybridge KT15 3NB
23 December 1988
DISTRIBUTION
This document (BPS/BSE/1) may be updated. Enquiries should be addressed to the Head of Department. Tel 09323 41111, Ext 450 88/01.06/1.5 ============
BOVINE SPONGIFORM ENCEPHALOPATHY - implications for biological products
At present it seems reasonable to assume that BSE is caused by an unconventional scrapie-like agent, which is widespread within the UK cattle population. The current thinking is that the most likely source is meat and bone meal containing sheep by-products and incorporated into cattle, especially calf, feed. This being so, it is possible that the problem is restricted to the UK. In this case, there are no BSE-related implications for substances from abroad.
The extent of the condition in the UK is unknown,but the number of cases is rising inexorably. There seem to be no breed-related effects, the lack of reports from beef breeds probably relates to the lower exposure of these animals to commercial feeds.
No data are available to assess the probability of agent spread from cattle to cattle, either vertically or horizontally. However, it must be assumed that both of these events, especially the former, will occur. There is no evidence from pork with scrapie, except as specified below, that incubating or clinical cases present differing risks of the agent being present in tissues. It must be assumed that all ages of cattle, foetal and post-natal, present a similar risk.
There are three main approaches to containing this potential threat, of which I consider only the third to be viable.
1) Everything derived from cattle represents a potential BSE threat. The use of such substances is not permitted unless they have undergone a process to inactivate this agent. The only acceptable treatment is two cycles of autoclaving at 126 C (20 psi) for 30 minutes, with cooling to <35 c="" div="" inbetween.="">
This will effectively stop the use of bovine serum and cell cultures in vaccine production, and the use of therapeutic bovine anti-serum. Serum albumin will also be adversely affected.
Tracing techniqnes Could be used to designate acceptable sources for bovine products.
At the present state of the epidemic this approach is unusable as the picture is changing almost daily. Even if sufficient data were available, the logistics of Collecting serum, for instance, would be unworkable in practice.
3) Risks should be assigned to particular products or groups of products, and action taken against these as necessary in light of the knowledge about the scrapie agent in natural and experimental hosts. There is a risk involved with this approach as there may be subtle differences between the distributions of BSE and scrapie agents, and knowledge of scrapie is in anyway incomplete. However, the risks associated with reliance on imported substances are probably greater. As a general rule, the harvesting of any substance from suspected or confirmed cases should not be allowed. Also, it should be remembered that there is no possibility of testing production components or final product for the presence of BSE agent.
a) SERUM AND SERUM PRODUCTS: There is no evidence that serum from scrapie
87/12.00/1.1 =============
infected animals contains any infectious agent, although many attempts have been made. It seems reasonable to assume that 'the use of these substances is not associated with a risk of BSE agent contamination. It may not be unreasonable, though, for manufacturers to use for anti-serum production only animals with the lowest risk of exposure to the BSE agent. At the present time this means those derived from suckler herds not feeding concentrates, and with no history of contact with BSE.
b) OTHER TISSUES: Tissue distribution of scrapie infectivity is uneven. Maximum titres occur in neural and 'lymphoid' tissues. Lower amounts occur in placenta, salivary and adrenal glands, pancreas, liver (from work in sheep and goats) ,Lung, kidney, intestine and uterus (from additional work in mice). The use of these tissues should be firmly discouraged. If such use is necessary, then the product should be treated as 1 above. Traces of scrapie agent have also been isolated from muscle late in the incubation period of the disease. This constitutes a smaller risk, given the low titre and short duration of its presence. A single cycle of 126 C for 30 mins is probably adequate treatment for such products, which tend to be the somewhat diverse 'peptones' used in bacteriological media and sometimes as freeze-drying stabilzers. Tnere are two special cases to consider - hormones and similar extracts, and ce11 cultures. HORMONES etc.: Although the extraction processes involve the use of various organic solvents, which tend to have a deliterious effect on scrapie infectivity, extracts must be considered to be potentially contaminated - indeed Creutzfeld-Jakob disease has been transmitted by the use of human growth hornnone extracted from cadaver pituitaries. It is therefor not possible to regard bovine gland extracts as deserving special consideration; they must be autoclaved as above. Such products are not likely to be effective after such treatment. The use of pituitary extracts for super-ovulation is not apparently controlled under the Medicines Act. This is an anomaly which requires urgent reconsideration. CELL CULTURES: Primary cell cultures could transit an unconventional agent mechanically. Their use should not be permitted. Given the probability of vertical transnission, it is not possible to set up 'SPF' herds to get around this problem. Cell lines are a different matter. No unconventional agent nas been grown in cell culture. It seems reasonable to assume that the agent of BSE will not replicate in cell cultures either. There is also no evidence that whatever constitutes a 'genome' in these agents can integrate into host cell genome, so the only danger in the use of cell lines is again one of mechanical transmission. With the number of passages required to produce a validated cell genome there seems no real need to impose any general BSE-related requirements. This is, of course, a theoretical argument. Given that the risk, regardless of its absolute size, will be related to the degree of contamination of the original tissue, the use of cells derived from tissues that could carry a high burden of infectivity (neural and 'lymphoid') should not be allowed.
c) SECRETIONS and EXCRETIONS: Scrapie agents have not keen isolated from any natural secretions or excretions. This includes saliva, milk, urine and faeces. It seems reasonable to regard these materials as not constituting a BSE-related risk. However, it is assumed that one way that scrapie is spread is through the ingestion of infected placentae, with the agent passing through the gut and being excreted in faeces. It may be possible to question the use of bovine faeces, or at least products derived from them. This has implications for lung worm vaccines. Calves, though, are not major consumers of placentae, and they are maintained in quarantine for a period before use, so there doesn't seem to be an appreciable risk. The situation with bile may not be so straightforward. I don't know that bile has ever been looked at for scrapie infectivity. One could argue that the absence of agent in faeces suggests that it isn't present in bile, but there must be a considerable dilution effect. It is probably better to err on the safe side and
87/12.00/1.2 =============
require a single 126 C, 30 min cycle for this substance.
d) OVA and SPERM: The situation here is uncertain, but of no direct concern for biological products in Medicines Act terms. However, the areas of AI and embryo transfer require some investigation.
Peter Luff Dec 1987
87/12.00/1.3 ============= ANNEX 3 VLM? Minutes of the Biological Committee Meeting Bovine Spongiform Encephalopathy SP 3663.2
7.1 A paper from BP & S on the implications of Bovine Spongiform Encephalopathy for biological products was distributed for discussion.
7.2 The chairman outlined what was currently known about the disease in the following points:
1. Where the BSE agent came from was speculative at present.
2. There was no evidence that any species other than cattle was affected.
3. Cases of the disease had been reported from the Channel Islands.
4. The position in other countries was not known as investigations were at an early stage.
5. Work was being undertaken to see if the BSE agent could be transferred from animal to animal. The work would be done at different laboratories, including the CVL and would involve studies in cattle, hamsters, mice and primates.
7.3 It was noted that BSE was closely related and biologically similar with the scrapie agent.
7.4 The paper outlined 3 options:
1. All vaccines containing bovine products should be heat treated for 2 cycles of 126°C for 30 minutes. This was considered a severe untenable option as it would affect virtually all product licence holders.
2. Vaccine manufacturers would only use bovine products from herds, certified as free of clinical disease.
This option was considered a satisfactory option by some members of the committee..
3. All bovine tissues should be assigned to different risk groups and each group would be treated separately. The suggested groups were based on work that had been generated using the scrapie agent. There was concern about the use of brain, neural and lymphoid tissue and pituitary. (It was noted with concern that hormone extracts could be manufactured by a veterinary surgeon for administration to animals under his care without any Medicines Act Control). Use of these products should be discouraged. Conversely serum products were considered to be of little concern.
This option was considered the most approptiate by (can't read...tss)
88/02.03/1.1 ============
VLM? MINUTES OF THE BIOLOGICAL COMMITTEE MEETING HELD ON 3rd February
Bovine Spongiform Encephalopathy SP 3663.2
7.5 After considerable discussion it was agreed that no action be taken at present but that the situation should be reviewed again in six months time unless any new developments within that time required urgent action. It was agreed to inform senior MAFF staff of the conclusions of the Committee. It was also agreed to assess whether certification of clinically free animals was feasible.
88/02.03/1.2
[more to come...TSS]
############ http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############
*** U.S.A. 50 STATE BSE MAD COW CONFERENCE CALL Jan. 9, 2001***
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002]Not Applicable
BACKGROUND OF THE INVENTION
[0003]The field of embryo transfer is growing in each animal sector in which multiple offspring are desirable. There were over 130,000 donor cattle superovulated worldwide in 2006 and the number of transferred embryos increased by 10% to over 670,000 (IETS Newsletter December 2007). In the United States, there were an estimated 52,000 donors superovulated in 2006 (AETA Annual Report 2006). The current superovulation protocols all require multiple injections of Follicle Stimulating Hormone (FSH) twice daily over the course of at least 4 days. The FSH currently used is animal derived, impure and has the propensity to be infectious. The invention described herein is a long-acting FSH analog that is effective in causing superovulation with a single injection. Furthermore, this FSH analog is highly purified and free of infectious vectors and other contaminants.
[0004]There are over nine million dairy cows in the United States, over one million in Canada and over fifty million worldwide. The dairy industry is extremely competitive and the ability of a dairy to increase the efficiency of breeding and to maintain pregnancies post insemination is critical to the profitability of the producer. It is estimated that the cost of a non-pregnant cow is about five dollars per day. It is further estimated that current inseminations result in approximately twenty to thirty-five percent pregnant cows at day 45 and of those cows ninety to ninety-five percent deliver calves at the end of the 283-day gestation period. However, reproductive efficiency in dairy cattle has been declining steadily over a prolonged period of time. The magnitude and the consistency of this trend are of great importance to the dairy industry and amount to a steady decline of approximately one percent in first service conception rates per year for the last ten years. The impact of this change in productivity has not been readily apparent, because individual cow milk production has increased by twenty percent over the same period. In the long run, the dairy industry cannot afford to continue the current rate of declining reproductive performance.
[0005]Declining reproductive efficiency of dairy cattle has been observed throughout the United States, and other parts of the world where milk production has been increasing (Lucy, M. C. (2001) "Reproductive loss in high-producing dairy cattle: Where will it end?," J. Dairy Sci., 84:1277-1293; Roche et al. (2000) "Reproductive management of postpartum cows," Anim. Reprod. Sci., 60-61:703-712; Royal et al. (2000) "Declining fertility in dairy cattle: changes in traditional and endocrine parameters of fertility," Anim. Sci., 70:487-502; and Macmillan et al. (1996) "The effects of lactation on the fertility of dairy cows" Aust. Vet. J, 73:141-147). Numerous features may negatively influence fertility in dairy cows, including negative energy balance and disease events such as retained placenta, ketosis, cystic ovary, and mastitis (Lucy 2001, supra; and Staples et al. (1990) "Relationship between ovarian activity and energy status during the early postpartum period of high producing dairy cows," J. Dairy Sci., 73:938-947). Furthermore, a prominent trend in the U.S. dairy industry is decreased number of dairy farms, steadily increasing herd size, and movement of dairy production to the western states (USDA National Agricultural Statistics Service, http//www.usda.gov/nass). Larger herd size may contribute to decreased reproductive performance because of the associated changes in the dairy labor force and cow management, resulting in poorly trained or over tasked workers identifying estrus behavior, performing artificial insemination, conducting estrus synchronization programs, and identifying and treating sick cows (Lucy 2001, supra). Heat stress, which occurs throughout much of the year in western and southwestern US dairy herds, has significant negative impact on cattle fertility (Wolfenson et al. (2000) "Impaired reproduction in heat-stressed cattle: basic and applied aspects," Anim. Reprod. Sci., 60-61:535-547).
[0006]The primary revenue source in the dairy industry is milk production. Progress in genetics and management of dairy cows has led to remarkable increases in milk production throughout the last several decades, with a twenty percent increase in per-cow production in the last ten years alone (USDA National Agricultural Statistics Service, http//www.usda.gov/nass). In order to maintain high herd productivity, however, cows must become pregnant and deliver a calf so that the lactation cycle is renewed. Additionally, sufficient numbers of heifers must be produced to replace older cows. Therefore, the future productivity of the dairy industry is very dependent on the maintenance of fertility and reproduction.
[0007]The ability to increase reproductive performance in horses, cattle or other ungulates would have a significant economic benefit to owners. This can be achieved through increasing fertility as well as improving pregnancy maintenance throughout the gestation period to prevent pregnancy losses. Recent studies with ultrasonic pregnancy detection demonstrate embryonic losses in cattle of at least 20% between 28 and 60 days of pregnancy (Pursley et al. (1998) "Effect of time of artificial insemination on pregnancy rates, calving rates, pregnancy loss, and gender ratio after synchronization of ovulation in lactating dairy cows," J. Dairy Sci., 81:2139-2144; and Vasconcelos et al. (1997) "Pregnancy rate, pregnancy loss, and response to heat stress after AI at 2 different times from ovulation in dairy cows" Biol. Reprod., 56 (Supp. 1):140). There are likely even higher losses prior to 28 days that are undetected by ultrasound examination (Lucy 2001, supra). Data suggest that modern dairy cows fail to establish pregnancy because of suboptimal uterine environment (Gustafsson, H. and K. Larsson (1985) "Embryonic mortality in heifers after artificial insemination and embryo transfer: differences between virgin and repeat breeder heifers," Res. Vet. Sci., 39:271-274). Although there are numerous possible factors that could be responsible for embryonic losses, one potential cause is low blood progesterone concentration.
[0008]Currently, several hormone therapies are used to increase fertility or to maintain pregnancy. Thatcher et al. (2001 Theriogenology 55:75-89) describes the effects of hormonal treatments on the reproductive performance of cattle. Hormonal treatments include administration of bovine somatotrophin (bST) and human chorionic gonadotropin (hCG). D'Occhio et al. (2000 Anim. Reprod. Sci. 60-61:433-442) describes various strategies for beef cattle management using gonadotropin releasing hormone (GnRH) agonist implants. De Rensis et al. (2002 Theriogenology 58(9):1675-1687) describes the effect on dairy cows of administering GnRH or hCG before artificial insemination. Martinez et al. (1999 Anim. Reprod. Sci. 57:23-33) describes the ability of porcine luteinizing hormone (LH) and GnRH to induce follicular wave emergence in beef heifers on Days 3, 6, and 9 of the estrus cycle, after ovulation (Day 0), without insemination. Santos et al. (2001 J. Animal Science 79:2881-2894) describes the effect on reproductive performance of intramuscular administration of 3,300 IU of hCG to high-producing dairy cows on Day 5 after artificial insemination. Lee et al. (1983 Am. J. Vet. Res. 44(11):2160-2163) describes the effect on dairy cows of administering GnRH at the time of artificial insemination. U.S. Pat. Nos. 5,792,785 (issued Aug. 11, 1998) and 6,403,631 (issued Jun. 11, 2002) describe methods and compositions for administering melatonin before and after insemination to enhance pregnancy success in an animal. Chagas e Silva et al. (2002 Theriogenology 58(1):51-59) describes plasma progesterone profiles following embryo transfer in dairy cattle. Weems et al. (1998 Prostaglandins and other Lipid Mediators) describes the effects of hormones on the secretion of progesterone by corpora lutea (CL) from non-pregnant and pregnant cows. U.S. Pat. No. 4,780,451 (issued Oct. 25, 1988) describes compositions and methods using LH and follicle stimulating hormone (FSH) to produce superovulation in cattle. Farin et al. (1988 Biol. Reprod. 38:413-421) describes the effect on ovine luteal weight of intravenous administration of 300 IU of hCG on Days 5 and 7.5 of the estrus cycle, without insemination. Hoyer and Niswender (1985 Can. J. Physiol. Pharmacol. 63(3):240-248) describe the regulation of steroidogenesis in ovine luteal cells. Juengel and Niswender (1999 J. Reprod. Fertil. Suppl. 54:193-205) describe the molecular regulation of luteal progesterone in domestic ruminants. U.S. Pat. No. 5,589,457 (issued Dec. 31, 1996) describes methods for synchronizing ovulation in cattle using GnRH, LH, and/or hCG and PGF2a.
[0009]Many of these treatments use hormones or hormone analogs from the glycoprotein hormone family, which consists of the pituitary proteins luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroid stimulating hormone (TSH) and chorionic gonadotropin (CG). The gonadotropins, which include CG, FSH and LH, are essential for reproductive function. They are heterodimers composed of two non-covalently associated a and ß subunits. Both subunits are glycosylated, containing asparagine (N)-linked oligosaccharides and, in the case of the CGß subunit, O-linked carbohydrates are also present in a cluster of amino acids at the C-terminus. The individual human ß subunits are encoded by separate genes, and the LHß and CGß proteins are structurally and functionally similar; having more than 80% amino acid identity (Pierce J G, Parsons (1981) "Glycoprotein hormones: structure and function," Biochem. 50:465-495). Within a species, the a subunit amino acid sequence is common to all four hormones (Pierce J G, Parsons (1981) Biochem. 50:465-495).
[0010]In order to use gonadotropins to improve reproduction efficiency in animals, the availability of purified proteins is essential. Currently, the sources for gonadotropins are serum and whole pituitary extracts. To obtain sufficient quantities of these native hormones for such work is expensive and difficult. Pituitary extracts can be effective reproductive therapeutics but contain contaminants and may vary in their amounts of LH and FSH. Preparations of pure pituitary gonadotropins without cross-contamination are not readily available. Given the problem of animal-to-animal variation of native gonadotropins and the charge heterogeneity in the N-linked carbohydrates, the ability to generate the corresponding recombinant proteins will yield gonadotropins of a more homogeneous composition that can be standardized with respect to mass and bioactivity. Such proteins will be critical for calibrating clinical laboratory assays and for breeding management, such as shortening the time to ovulation in transitional and cycling mares for natural breeding and artificial insemination. The use of recombinant forms, as opposed to hormones extracted from serum and pituitary tissue, would avoid the co-contamination of pathogens and agents with a propensity to cause prion related diseases.
snip...see more ;
Review Risks of transmitting ruminant spongiform encephalopathies (prion diseases) by semen and embryo transfer techniques
References and further reading may be available for this article. To view references and further reading you must purchase this article.
A.E. Wrathalla, , , G.R. Holyoakb, I.M. Parsonsonc and H.A. Simmonsa
aAnimal Services Unit, Veterinary Laboratories Agency, Woodham Road, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom
bOklahoma State University, Center for Veterinary Health Sciences, Stillwater, OK 74078, USA
c1 Coape St., Cheltenham, Victoria 3192, Australia
Received 18 March 2008; revised 12 May 2008; accepted 14 May 2008. Available online 30 June 2008.
Abstract Early experiments suggested that scrapie transmission via sheep embryos was a possibility, and gave rise to much controversy. However, when account is taken of the complex genetic effects on ovine susceptibility to scrapie, and of the several different scrapie strains with different clinical and pathological effects, the overall conclusion now is that transmission of classical scrapie by embryo transfer is very unlikely if appropriate precautions are taken. Recent embryo transfer studies have confirmed this. Other studies in sheep have shown that from about the middle of pregnancy the placental trophoblast is liable to scrapie infection in genetically susceptible ewes if the fetus is also susceptible. Since the contrary is also true, use of resistant ewes as embryo recipients could add to the safety of the embryo transfer, at least for classical scrapie. There has been little recent research on scrapie transmission via semen in sheep, and, with hindsight, the early studies, though negative, were inadequate. There is scant information on scrapie transfer via goat semen or embryos, although one study did find that bovine spongiform encephalopathy (BSE) was not transmitted via goat embryos. In cattle it has been shown that, if appropriate precautions are taken, the risks of transmitting BSE via semen and in vivo-derived embryos are negligible, and this conclusion has gained worldwide acceptance. Research on TSE transmission via reproductive technologies in deer has not yet been done, but information on the pathogenesis and epidemiology of chronic wasting disease (CWD) of deer, and on transmission risks in other species, provides optimism that transmission of CWD via semen and embryos of deer is unlikely. The presence of TSE infectivity in blood and various other tissues of infected animals, particularly sheep, gives rise to concerns that certain biological products currently used in reproductive technologies, e.g. pituitary gonadotrophins for superovulation, and certain tissue and blood products used in semen and embryo transfer media, could carry TSE infectivity. Instruments such as laparoscopes used for insemination, and for collection and transfer of embryos, especially in small ruminants, are also a concern because effective decontamination can be very difficult.
Keywords: Semen; Embryos; Placenta; Ruminants; Spongiform encephalopathies; Prion diseases; Import–export
SUNDAY, AUGUST 02, 2015
TEXAS CWD, Have you been ThunderStruck, deer semen, straw bred bucks, super ovulation, and the potential TSE Prion connection, what if?
TEXAS CWD, Have you been ThunderStruck, deer semen, straw bred bucks, super ovulation, and the potential TSE Prion connection, what if?
THURSDAY, MARCH 30, 2017
Amyloid‑β accumulation in the CNS in human growth hormone recipients in the UK
Passage of scrapie to deer results in a new phenotype upon return passage to sheep
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies
Location: Virus and Prion Research
Title: Passage of scrapie to deer results in a new phenotype upon return passage to sheep) Author
item Greenlee, Justin item Kokemuller, Robyn item Moore, Sarah item West Greenlee, N
Submitted to: Prion
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2017
Publication Date: N/A
Citation: N/A
Interpretive Summary:
Technical Abstract: Aims: We previously demonstrated that scrapie has a 100% attack rate in white-tailed deer after either intracranial or oral inoculation. Samples from deer that developed scrapie had two different western blot patterns: samples derived from cerebrum had a banding pattern similar to the scrapie inoculum, but samples from brainstem had a banding pattern similar to CWD. In contrast, transmission of CWD from white-tailed deer to sheep by the intracranial route has a low attack rate and to-date oronasal exposure has been unsuccessful. The purpose of this study was to determine if sheep are susceptible to oronasal exposure of the scrapie agent derived from white-tailed deer.
Methods: At approximately 5 months of age, Suffolk sheep of various PRNP genotypes were challenged by the oronasal route with 10% brain homogenate derived from either the cerebrum or the brainstem of scrapie-affected deer. Genotypes represented in each inoculation group were VV136RR154QQ171 (n=2), AA136RR154QQ171 (n=2), and AV136RR154QR171 (n=1). After inoculation, sheep were observed daily for clinical signs. Upon development of clinical signs, sheep were killed with an overdose of pentobarbital sodium and necropsied. Tissue samples were tested for the presence of PrPSc by EIA, western blot, and immunohistochemistry (IHC). The No. 13-7 scrapie inoculum used for the deer has a mean incubation period of 20.1 months in sheep with the AA136RR154QQ171 genotype and 26.7 months in sheep with the VV136RR154QQ171 genotype.
Results: Sheep inoculated oronasally with WTD derived scrapie developed disease, but only after inoculation with the inoculum from the cerebrum that had a scrapie-like profile. The first sheep to develop clinical signs at approximately 29 months post inoculation had the VV136RR154QQ171 genotype. Eventually sheep of the AA136RR154QQ171 genotype developed clinical signs, but at a mean incubation of 52 months. At 62 months post-inoculation, none of the sheep inoculated with material from the deer brainstem have developed clinical disease.
Conclusions: The No. 13-7 inoculum used in the original deer experiment readily infects white-tailed deer and sheep of various genotypes by the oronasal route. When inoculum is made from different brain regions of No 13-7 scrapie-infected deer from either cerebrum with a scrapie-like western blot pattern or brainstem with a CWD-like western blot pattern, sheep with the VV136RR154QQ171 genotype are the first to develop clinical signs. This is in contrast to the original No. 13-7 inoculum that has a faster incubation period in sheep with the AA136RR154QQ171 genotype. Similar to experiments conducted with CWD, sheep oronasally inoculated with brainstem material from deer with a CWD-like molecular profile have no evidence of disease after 62 months of incubation. While scrapie is not known to occur in free-ranging populations of white-tailed deer, experimental cases are difficult to differentiate from CWD. This work raises the potential concern that scrapie infected deer could serve as a confounding factor to scrapie eradication programs as scrapie from deer seems to be transmissible to sheep by the oronasal route.
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Title: Transmission of the agent of sheep scrapie to deer results in PrPSc with two distinct molecular profiles Authors item Greenlee, Justin item Moore, Sarah - item Smith, Jodi item West Greenlee, Mary - item Kunkle, Robert Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: March 31, 2015 Publication Date: May 25, 2015 Citation: Greenlee, J., Moore, S.J., Smith, J.., West Greenlee, M.H., Kunkle, R. 2015. Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease and distinct from the scrapie inoculum.
Prion 2015. p. S62.
Technical Abstract: The purpose of this work was to determine susceptibility of white-tailed deer (WTD) to the agent of sheep scrapie and to compare the resultant PrPSc to that of the original inoculum and chronic wasting disease (CWD). We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (IN); n=5) with a US scrapie isolate. All scrapie-inoculated deer had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform encephalopathy, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blotting (WB) revealed PrPSc with 2 distinct molecular profiles. WB on cerebral cortex had a profile similar to the original scrapie inoculum, whereas WB of brainstem, cerebellum, or lymph nodes reveal PrPSc with a higher profile resembling CWD. Homogenates with the 2 distinct profiles from WTD with clinical scrapie were further passaged to mice expressing cervid prion protein and intranasally to sheep and WTD. In cervidized mice, the two inocula have distinct incubation times. Sheep inoculated intranasally with WTD derived scrapie developed disease, but only after inoculation with the inoculum that had a scrapie-like profile. The WTD study is ongoing, but deer in both inoculation groups are positive for PrPSc by rectal mucosal biopsy.
In summary, this work demonstrates that WTD are susceptible to the agent of scrapie, two distinct molecular profiles of PrPSc are present in the tissues of affected deer, and inoculum of either profile type readily passes to deer.
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Title: Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease
Authors item Greenlee, Justin item Moore, S - item Smith, Jodi - item Kunkle, Robert item West Greenlee, M - Submitted to: American College of Veterinary Pathologists Meeting Publication Type: Abstract Only Publication Acceptance Date: August 12, 2015
Publication Date: N/A
Technical Abstract: The purpose of this work was to determine susceptibility of white-tailed deer (WTD) to the agent of sheep scrapie and to compare the resultant PrPSc to that of the original inoculum and chronic wasting disease (CWD). We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (IN); n=5) with a US scrapie isolate. All scrapie-inoculated deer had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform encephalopathy, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blotting (WB) revealed PrPSc with 2 distinct molecular profiles. WB on cerebral cortex had a profile similar to the original scrapie inoculum, whereas WB of brainstem, cerebellum, or lymph nodes revealed PrPSc with a higher profile resembling CWD. Homogenates with the 2 distinct profiles from WTD with clinical scrapie were further passaged to mice expressing cervid prion protein and intranasally to sheep and WTD. In cervidized mice, the two inocula have distinct incubation times. Sheep inoculated intranasally with WTD derived scrapie developed disease, but only after inoculation with the inoculum that had a scrapie-like profile. The WTD study is ongoing, but deer in both inoculation groups are positive for PrPSc by rectal mucosal biopsy.
In summary, this work demonstrates that WTD are susceptible to the agent of scrapie, two distinct molecular profiles of PrPSc are present in the tissues of affected deer, and inoculum of either profile readily passes to deer.
*** 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.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
Jodi D. Smith, Justin J. Greenlee, and Robert A. Kunkle; Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS
Interspecies transmission studies afford the opportunity to better understand the potential host range and origins of prion diseases. Previous experiments demonstrated that white-tailed deer are susceptible to sheep-derived scrapie by intracranial inoculation. The purpose of this study was to determine susceptibility of white-tailed deer to scrapie after a natural route of exposure. Deer (n=5) were inoculated by concurrent oral (30 ml) and intranasal (1 ml) instillation of a 10% (wt/vol) brain homogenate derived from a sheep clinically affected with scrapie. Non-inoculated deer were maintained as negative controls. All deer were observed daily for clinical signs. Deer were euthanized and necropsied when neurologic disease was evident, and tissues were examined for abnormal prion protein (PrPSc) by immunohistochemistry (IHC) and western blot (WB). One animal was euthanized 15 months post-inoculation (MPI) due to an injury. At that time, examination of obex and lymphoid tissues by IHC was positive, but WB of obex and colliculus were negative. Remaining deer developed clinical signs of wasting and mental depression and were necropsied from 28 to 33 MPI. Tissues from these deer were positive for scrapie by IHC and WB. Tissues with PrPSc immunoreactivity included brain, tonsil, retropharyngeal and mesenteric lymph nodes, hemal node, Peyer’s patches, and spleen. This work demonstrates for the first time that white-tailed deer are susceptible to sheep scrapie by potential natural routes of inoculation. In-depth analysis of tissues will be done to determine similarities between scrapie in deer after intracranial and oral/intranasal inoculation and chronic wasting disease resulting from similar routes of inoculation.
see full text ; http://www.usaha.org/Portals/6/Reports/2010/report-cwal-2010.pdf
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed deer Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture; Agricultural Research Service, National Animal Disease Center; Ames, IA USA
White-tailed deer are susceptible to the agent of sheep scrapie by intracerebral inoculation
snip...
It is unlikely that CWD will be eradicated from free-ranging cervids, and the disease is likely to continue to spread geographically [10]. However, the potential that white-tailed deer may be susceptible to sheep scrapie by a natural route presents an additional confounding factor to halting the spread of CWD. This leads to the additional speculations that 1) infected deer could serve as a reservoir to infect sheep with scrapie offering challenges to scrapie eradication efforts and 2) CWD spread need not remain geographically confined to current endemic areas, but could occur anywhere that sheep with scrapie and susceptible cervids cohabitate. This work demonstrates for the first time that white-tailed deer are susceptible to sheep scrapie by intracerebral inoculation with a high attack rate and that the disease that results has similarities to CWD. These experiments will be repeated with a more natural route of inoculation to determine the likelihood of the potential transmission of sheep scrapie to white-tailed deer. If scrapie were to occur in white-tailed deer, results of this study indicate that it would be detected as a TSE, but may be difficult to differentiate from CWD without in-depth biochemical analysis.
2012
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed deer Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture; Agricultural Research Service, National Animal Disease Center; Ames, IA USA
snip...
The results of this study suggest that there are many similarities in the manifestation of CWD and scrapie in WTD after IC inoculation including early and widespread presence of PrPSc in lymphoid tissues, clinical signs of depression and weight loss progressing to wasting, and an incubation time of 21-23 months. Moreover, western blots (WB) done on brain material from the obex region have a molecular profile similar to CWD and distinct from tissues of the cerebrum or the scrapie inoculum. However, results of microscopic and IHC examination indicate that there are differences between the lesions expected in CWD and those that occur in deer with scrapie: amyloid plaques were not noted in any sections of brain examined from these deer and the pattern of immunoreactivity by IHC was diffuse rather than plaque-like.
*** After a natural route of exposure, 100% of WTD were susceptible to scrapie. Deer developed clinical signs of wasting and mental depression and were necropsied from 28 to 33 months PI. Tissues from these deer were positive for PrPSc by IHC and WB. Similar to IC inoculated deer, samples from these deer exhibited two different molecular profiles: samples from obex resembled CWD whereas those from cerebrum were similar to the original scrapie inoculum. On further examination by WB using a panel of antibodies, the tissues from deer with scrapie exhibit properties differing from tissues either from sheep with scrapie or WTD with CWD. Samples from WTD with CWD or sheep with scrapie are strongly immunoreactive when probed with mAb P4, however, samples from WTD with scrapie are only weakly immunoreactive. In contrast, when probed with mAb’s 6H4 or SAF 84, samples from sheep with scrapie and WTD with CWD are weakly immunoreactive and samples from WTD with scrapie are strongly positive. This work demonstrates that WTD are highly susceptible to sheep scrapie, but on first passage, scrapie in WTD is differentiable from CWD.
2011
*** After a natural route of exposure, 100% of white-tailed deer were susceptible to scrapie.
Sunday, October 25, 2015 USAHA Detailed Events Schedule – 119th USAHA Annual Meeting CAPTIVE LIVESTOCK CWD SCRAPIE TSE PRION
Thursday, December 08, 2016
USDA APHIS National Scrapie Eradication Program October 2016 Monthly Report Fiscal Year 2017 atypical NOR-98 Scrapie
MONDAY, MARCH 13, 2017
CHRONIC WASTING DISEASE CWD TSE PRION UDATE March 13, 2017
SATURDAY, JANUARY 14, 2017
CHRONIC WASTING DISEASE CWD TSE PRION GLOBAL UPDATE JANUARY 14, 2017
WEDNESDAY, MARCH 15, 2017
In vitro amplification of H-type atypical bovine spongiform encephalopathy by protein misfolding cyclic amplification
"When considering the atypical L-BSE and H-BSE diseases of cattle, they have been assessed in both non-human primate and transgenic mouse bioassays (with mice transgenic for human PRNP) and both model systems indicate that H-BSE and L-BSE may have increased zoonotic potential compare with C-BSE. The detection of all types of BSE is therefore of significant importance."
Wednesday, December 21, 2016
TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES 2016 ANNUAL REPORT ARS RESEARCH
Thursday, October 22, 2015
Former Ag Secretary Ann Veneman talks women in agriculture and we talk mad cow disease USDA and what really happened
Thursday, December 08, 2016
USDA APHIS National Scrapie Eradication Program October 2016 Monthly Report Fiscal Year 2017 atypical NOR-98 Scrapie
*** 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
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
Monday, May 02, 2016
*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***
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 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
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.
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
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.
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).***
*** 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.
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission
*** Title: Pathological features of chronic wasting disease in reindeer and demonstration of horizontal transmission
*** December 2016 CDC Emerging Infectious Disease Journal CWD Horizontal Transmission
*** 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.
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
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.
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 ***
*** Infectious agent of sheep scrapie may persist in the environment for at least 16 years ***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
cwd resistant cervid???
***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
Saturday, May 28, 2016
*** Infection and detection of PrPCWD in soil from CWD infected farm in Korea Prion 2016 Tokyo ***
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
the tse prion aka mad cow type disease is not your normal pathogen.
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.
cwd to humans, consumption, exposure, sub-clinical, iatrogenic, what if ?
Wednesday, September 7, 2016
*** An assessment of the long-term persistence of prion infectivity in aquatic environments
Detection of protease-resistant cervid prion protein in water from a CWD-endemic area
The data presented here demonstrate that sPMCA can detect low levels of PrPCWD in the environment, corroborate previous biological and experimental data suggesting long term persistence of prions in the environment2,3 and imply that PrPCWD accumulation over time may contribute to transmission of CWD in areas where it has been endemic for decades. This work demonstrates the utility of sPMCA to evaluate other environmental water sources for PrPCWD, including smaller bodies of water such as vernal pools and wallows, where large numbers of cervids congregate and into which prions from infected animals may be shed and concentrated to infectious levels.
TUESDAY, MARCH 28, 2017
Passage of scrapie to deer results in a new phenotype upon return passage to sheep
Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Location: Virus and Prion Research
Title: Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Author item Moore, Sarah item Kunkle, Robert item Kondru, Naveen item Manne, Sireesha item Smith, Jodi item Kanthasamy, Anumantha item West Greenlee, M item Greenlee, Justin
Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 3/15/2017 Publication Date: N/A Citation: N/A Interpretive Summary:
Technical Abstract: Aims: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of cervids. We previously demonstrated that disease-associated prion protein (PrPSc) can be detected in the brain and retina from pigs challenged intracranially or orally with the CWD agent. In that study, neurological signs consistent with prion disease were observed only in one pig: an intracranially challenged pig that was euthanized at 64 months post-challenge. The purpose of this study was to use an antigen-capture immunoassay (EIA) and real-time quaking-induced conversion (QuIC) to determine whether PrPSc is present in lymphoid tissues from pigs challenged with the CWD agent. Methods: At two months of age, crossbred pigs were challenged by the intracranial route (n=20), oral route (n=19), or were left unchallenged (n=9). At approximately 6 months of age, the time at which commercial pigs reach market weight, half of the pigs in each group were culled (<6 challenge="" groups="" month="" pigs="" remaining="" the="">6 month challenge groups) were allowed to incubate for up to 73 months post challenge (mpc). The retropharyngeal lymph node (RPLN) was screened for the presence of PrPSc by EIA and immunohistochemistry (IHC). The RPLN, palatine tonsil, and mesenteric lymph node (MLN) from 6-7 pigs per challenge group were also tested using EIA and QuIC. Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 5="" 6="" at="" by="" detected="" eia.="" examined="" group="" in="" intracranial="" least="" lymphoid="" month="" months="" of="" one="" pigs="" positive="" prpsc="" quic="" the="" tissues="" was="">6 months group, 5/6 pigs in the oral <6 4="" and="" group="" months="" oral="">6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%).
Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
CONFIDENTIAL
EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY
While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...
we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.
May I, at the outset, reiterate that we should avoid dissemination of papers relating to this experimental finding to prevent premature release of the information. ...
3. It is particularly important that this information is not passed outside the Department, until Ministers have decided how they wish it to be handled. ...
But it would be easier for us if pharmaceuticals/devices are not directly mentioned at all. ...
Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....
snip... see much more here ;
WEDNESDAY, APRIL 05, 2017
Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
FRIDAY, MARCH 31, 2017
TPWD UPDATE CWD TSE Prion 49 confirmed cases and unwanted firsts for Texas
FRIDAY, JANUARY 27, 2017
TEXAS, Politicians, TAHC, TPWD, and the spread of CWD TSE Prion in Texas
WEDNESDAY, MARCH 15, 2017
In vitro amplification of H-type atypical bovine spongiform encephalopathy by protein misfolding cyclic amplification
"When considering the atypical L-BSE and H-BSE diseases of cattle, they have been assessed in both non-human primate and transgenic mouse bioassays (with mice transgenic for human PRNP) and both model systems indicate that H-BSE and L-BSE may have increased zoonotic potential compare with C-BSE. The detection of all types of BSE is therefore of significant importance."
Tuesday, September 06, 2016
A comparison of classical and H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism in wild type and EK211 cattle following intracranial inoculation
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
Monday, June 20, 2016
Specified Risk Materials SRMs BSE TSE Prion Program
Monday, January 09, 2017
Oral Transmission of L-Type Bovine Spongiform Encephalopathy Agent among Cattle CDC Volume 23, Number 2—February 2017
MONDAY, JANUARY 16, 2017
APHIS Bovine Spongiform Encephalopathy (BSE): Ongoing Surveillance Program Last Modified: Jan 5, 2017
TUESDAY, APRIL 04, 2017
Please Support Funding for CDC and NPDPSC's Prion Disease Programs
kindest regards, terry...
No comments:
Post a Comment