Pathogens 2013, 2, 457-471; doi:10.3390/pathogens2030457
pathogens
ISSN 2076-0817
Review
Prions in Variably Protease-Sensitive Prionopathy: An Update
Wen-Quan Zou 1,2,3,4,5,6,*, Pierluigi Gambetti 1,3, Xiangzhu Xiao 1, Jue
Yuan 1, Jan Langeveld 7 and Laura Pirisinu 8
1 Department of Pathology Case Western Reserve University School of
Medicine, Cleveland, OH 44106, USA; E-Mails: pxg13@case.edu (P.G.);
xiangzhu.xiao@case.edu (X.X.); jue.yuan@case.edu (J.Y.)
2 Department of Neurology, Case Western Reserve University School of
Medicine, Cleveland, OH 44106, USA
3 National Prion Disease Pathology Surveillance Center, Case Western
Reserve University School of Medicine, Cleveland, OH 44106, USA
4 National Center for Regenerative Medicine, Case Western Reserve
University School of Medicine, Cleveland, OH 44106, USA
5 The First Affiliated Hospital, Nanchang University, Nanchang 330006,
Jiangxi Province, China
6 State Key Laboratory for Infectious Disease Prevention and Control,
National Institute for Viral Disease Control and Prevention, Chinese Center for
Disease Control and Prevention, Beijing 100050, China
7 Central Veterinary Institute of Wageningen UR, Lelystad 8200 AB, the
Netherlands; E-Mail: jan.langeveld@wur.nl (J.L.)
8 Department of Veterinary Public Health and Food Safety, Istituto
Superiore di Sanità, Viale Regina Elena 299 00161, Rome, Italy; E-Mail:
laura.pirisinu@guest.iss.it (L.P.)
* Author to whom correspondence should be addressed; E-Mail:
wenquan.zou@case.edu; Tel./Fax: +1-216-368-8993/+1-216-368-2546.
Received: 12 June 2013; in revised form: 28 June 2013 / Accepted: 2 July
2013 /
Published: 5 July 2013
Abstract: Human prion diseases, including sporadic, familial, and acquired
forms such as Creutzfeldt-Jakob disease (CJD), are caused by prions in which an
abnormal prion protein (PrPSc) derived from its normal cellular isoform (PrPC)
is the only known component. The recently-identified variably protease-sensitive
prionopathy (VPSPr) is characterized not only by an atypical clinical phenotype
and neuropathology but also by the deposition in the brain of a peculiar PrPSc.
Like other forms of human prion disease, the pathogenesis of VPSPr also
currently remains unclear. However, the findings of the peculiar features of
prions from VPSPr and of the possible association of VPSPr with a known genetic
prion disease linked with a valine to isoleucine mutation at residue 180 of PrP
reported recently, may be of great importance in enhancing our understanding of
not only this atypical human prion disease in particular, but also other prion
diseases in general. In this review, we highlight the physicochemical and
biological properties of prions from VPSPr and discuss the pathogenesis of VPSPr
including the origin and formation of the peculiar prions.
Keywords: prions; prion protein; prion disease; Creutzfeldt-Jakob disease
(CJD); variably protease-sensitive prionopathy (VPSPr);
Gerstmann-Sträussler-Scheinker (GSS); mutation; proteinase K; antibody;
glycosylation; glycoform-selective prion formation; transmissibility
SNIP...
Pathogens 2013, 2 466
8. Origin of Prions in VPSPr and fCJDV180I As mentioned above, prions from
VPSPr and fCJDV18°I are of unique physicochemical and biological properties.
Remarkably, they exhibit a high immunoreactivity with the 1E4 antibody but a
poor reactivity with 3F4 [5,6]. We have demonstrated that the two antibodies
have adjacent epitopes and especially the 3F4 epitope (PrP106-112) is next to
the C-terminus of the 1E4 epitope (PrP97-105) [9,40]. Because of the unique
localization of the two epitopes, it is most likely that all five-step like
rPrPSc fragments from the two diseases contain the 3F4 epitope. So, the poor
affinity of 3F4 for rPrPSc from VPSPr and fCJDV180I may indicate that there
might be some local structures or binding molecules that block the 3F4 epitope.
We have noticed that the affinity of 3F4 for rPrPSc from VPSPr was increased in
the preparations after purification steps compared to unpurified total brain
homogenates (Zou et al., unpublished data). Thus, purification procedures may
somehow remove the binding molecules or alter the local structures, which might
make the 3F4 epitope exposed. On the other hand, all these findings may also
suggest that PrPSc from VPSPr and fCJDV180I have an origin different from PrPSc
detected in other human prion diseases. Using the same 1E4 antibody, we
previously identified a PK-resistant PrP species termed insoluble PrPC (iPrPC)
in uninfected human brains and cultured cells [6,9,40,41,42]. The small amount
of PK-resistant PrP in uninfected brains and cells exhibited the same peculiar
immunoreactivity behavior: higher affinity for 1E4 but lower affinity for 3F4.
Remarkably, the resemblances of three PK-resistant PrP core fragments migrating
at ~20 kDa, 17 kDa and 7 kDa observed in VPSPr were detected with 1E4 in
uninfected human brains [43]. The same immunoreactivity behavior of iPrPC in
uninfected brains and rPrPSc in VPSPr and fCJDV180I suggests that they may share
a common molecular metabolic pathway or distribution and that VPSPr and
fCJDV180I may result from an increase in the amount of iPrPC [43].
SNIP...
9. Association between VPSPr and Other Prion Diseases
In addition to V180I and T183A mutations, three other naturally occurring
PrP mutations including D178N, F198S, and E200K linked to familial prion disease
have reportedly been associated with altered ratios of the three PrP glycoforms.
But all the three familial prion diseases do not have rPrPSc that lacks
diglycosylated form [39]. Moreover, the 1E4-preferentially detectable rPrPSc has
not been identified yet. The deposition in the brain of multiple small
PK-resistant PrPSc, especially the 7-kDa fragment is the molecular hallmark of
GSS [44]. Therefore, it is reasonable for us to anticipate some potential
association between GSS and VPSPr. Indeed, because of the long disease duration,
multiple PK-resistant PrP fragments, and variable PK-resistance of PrPSc, VPSPr
was once suspected to be the sporadic form of GSS associated with PrPA117V
mutation (GSSA117) [5]. However, we also observed different ratios and
immunoreactivity of PrPSc between VPSPr and GSSA117V in the same study. It is
known that GSS is frequently associated with a predominantly cerebellar
dysfunction and is mainly characterized by the deposition of multicentric
plaques in the cerebellum [39]. In contrast, VPSPr lacks typical multicentric
plaques while it exhibits dot-like staining or small plaque-like formations in
the cerebellum [5]. Whether VPSPr is the sporadic form of fCJDV180I or GSSA117V
needs to be further determined. It is conceivable that cells and animals
expressing human PrPV180I or PrPA117V will provide valid models for addressing
the outstanding questions.
Pathogens 2013, 2 467
The fact that a small PK-resistant rPrPSc migrating at ~6–7 kDa that has
been believed to be a molecular hallmark of various GSS is also detectable in
both VPSPr and Nor98 [2,5,7,34,35,44] may imply a possible association among
these diseases. To gain insights into their apparent similarity and difference
and to investigate possible relationships among them, we further compared the
small fragment from VPSPr, Nor98, various GSS linked to P102L, A117V, or F198S
PrP mutation [8,45]. It was demonstrated that VPSPr and Nor98 share both similar
and distinctive features. For instance, interestingly, they all have a core
rPrPSc fragment encompassing PrP97-142 while the fragment can have varied N- and
C-terminal cleavage sites (Table 1) [45].
10. Conclusions
Prions found in sporadic VPSPr are clearly different from those of all
other classic sporadic human prion diseases. Both VPSPr and fCJDV180I shares
similar physicochemical properties of PrPSc and a glycoform-selective prion
formation pathway. The finding of the effect of polymorphism at residue 129 on
the levels of rPrPSc and sPrPSc further emphasizes the role of the polymorphism
in the pathogenesis of human prion diseases. The two diseases specifically alter
glycosylation at the first glycosylation site at residue 181 of PrP, which may
involve a non-PrP protein that participates in regulating PrP glycosylation.
Because of similar immunoreactivity and enzymatic fragmentation, PrPSc in VPSPr
and fCJDV180I may have an origin similar to iPrPC. The possible correlation
between human VPSPr and sheep Nor98 is interesting but remains to be further
investigated. The low transmissibility of VPSPr and fCJDV180I may result from
altered posttranslational modifications including not only glycosylation but
also the glycophosphatidylinositol (GPI) anchor. Whether there are any changes
in GPI anchor remains unknown. Our current protein sequencing study and glycan
analysis of purified rPrPSc will provide insights into these issues. Future
studies with the two diseases and with cell and animal models expressing
PrPV180I mutation will help us understand the possible co-factors and molecular
mechanisms underlying the formation of the unique prions identified in VPSPr and
fCJDV180I.
Prions in Variably Protease-Sensitive Prionopathy- An ... - MDPI.com
_sporadic_ FFI,
_sporadic_ GSS,
and
_vpspr_
vpspr - None of the subjects had mutations in the PrP gene coding
region.
sporadic FFI - Genetic tests identified no prion protein (PrP) gene
mutation
Monday, January 14, 2013
snip...
Gambetti et al USA Prion Unit change another highly suspect USA mad cow
victim to another fake name i.e. sporadic FFI at age 16 CJD Foundation goes
along with this BSe
Only months later would Michael’s family learn the reason for his
degradation and death. An autopsy showed that the teenager died of sporadic
fatal insomnia, a subtype of Creutzfeldt-Jakob Disease.
In fact, Michael may be among the youngest ever to be affected by a
neurodegenerative disease without an inherited or outside cause.
Gambetti, who played a key role in the discovery of fatal insomnia,
theorizes that Michael’s illness was random, despite the odds. It may be that,
by chance or some unknown factor, Michael’s brain perfectly bred its own
pathogen.
snip...
sporadic GSS -
We report here an unusual sporadic case of Creutzfeldt-Jakob disease (CJD)
characterized by an abundance of prion protein (PrP)-immunopositive kuru and
multicentric but not florid plaques. Molecular genetic analysis of the PRNP open
reading frame region spanning codons 8-221 was performed. Neither deletion nor
insertion mutations were detected in the repeat area of the PRNP. No pathogenic
mutation was found in the sequenced region between codon 108-221. Restriction
analysis of the amplified fragment using restriction endonucleases DdeI, PvuII
and AluI did not show any of the previously described pathogenic mutations at
codon 102, 105, and 117 associated with Gerstmann-Sträussler-Scheinker (GSS).
The patient was heterozygous for the methionine/valine coding triplet at
polymorphic codon 129 of the PRNP gene by sequence, restriction endonuclease
analysis and hybridization with allele-specific nucleotides. Furthermore,
hybridization with 32P-labeled allele-specific oligonucleotides confirmed the
absence of pathogenic mutations at codons 102, 200 and 178. Such a case may
present a missing "link" between sporadic CJD and familial GSS.
Saturday July 6, 2013
Nor98 Prions Share Biochemical Features with Human
Gerstmann-Sträussler-Scheinker Disease and Variably Protease-Sensitive
Prionopathy
because there is _NO_ genetic link to that particular family, the theory of
a familial disease is out the door, in my opinion. there has to be a source,
route, and mode of transmission, if there is no genetic link to the
family.
SPONTANEOUS HAS NEVER EVER BEEN PROVEN IN ANY CASE OF HUMAN TSE, ESPECIALLY
IN 85%+ OF ALL HUMAN TSE PRION CASES, AND THE FOLLOWING STATEMENT HAS NO
SCIENTIFIC PROOF;
*** ''Gambetti, who played a key role in the discovery of fatal insomnia,
theorizes that Michael’s illness was random, despite the odds. It may be that,
by chance or some unknown factor, Michael’s brain perfectly bred its own
pathogen.''
WHAT POLITICAL TSE PRION SCIENCE HAS DONE, IS TAKEN THE WORDS OF THEORY AND
HYPOTHESIS FROM SCIENTIST, AND THEN PUT IT IN PRINT, MADE THEM FACT, a terrible and
unjust thing to do, for the scientific community, and society.
I would personally donate money to someone that WAS looking for a cause of
the sporadic CJD, i.e. 85%+ of all human TSE prion disease.
now, that’s just my opinion, after watching the ‘FDA TRAVELING ROAD SHOW’,
OR what I call the FDA TRAVELING THREE RING CIRCUS I.E. FDA, USDA, CDC.
(8:30 a.m.)
CHAIRMAN BROWN: My name is Dr. Paul Brown. Welcome to the FDA traveling
road show. We are asked yet once more by the FDA to consider a question of
theoretical risk in the absence of sufficient knowledge on which to base any
firm conclusion.
The issue before us today is that of excluding categories of American blood
donors who have either visited or resided for longer periods of time in Great
Britain. The issue is sufficiently delicate, as you see that we have been moved
outside the Beltway.
(Laughter.)
wonder who’s laughing now ???
no TSEAC MEETINGS IN HOW LONG ???
Wednesday, December 11, 2013
*** Detection of Infectivity in Blood of Persons with Variant and Sporadic
Creutzfeldt-Jakob Disease ***
I ALSO STRONGLY DISAGREE WITH THE STATEMENT;
'OR OUTSIDE CAUSE'
IF THERE IS NO ;
'WITHOUT AN INHERITED CAUSE'
THEN THERE MUST BE AN OUTSIDE CAUSE, AND I PROPOSED, IN SOME CASES, IT BE
IATROGENIC.
VPSPR TSE PRION IS TRANSMISSIBLE ;
please see ;
Conclusions. Preliminary results from transmission studies in bank voles
strongly support the notion that VPSPr is a transmissible prion disease.
Interestingly, VPSPr undergoes divergent evolution in the two genetic lines of
voles, with sCJD-like features in BvM109 and GSS-like properties in
BvI109.
GSS TSE PRION IS TRANSMISSIBLE ;
Acta Neuropathol. 1984;64(1):85-8.
Experimental transmission of human subacute spongiform encephalopathy to
small rodents. IV. Positive transmission from a typical case of
Gerstmann-Sträussler-Scheinker's disease.
Tateishi J, Sato Y, Nagara H, Boellaard JW.
Abstract
Spongiform encephalopathy was transmitted to mice from a patient belonging
to the "Sch" family with Gerstmann-Sträussler-Scheinker's disease (GSS).
Incubation periods in the first passage were much shorter than those in mice
infected with Creutzfeldt-Jakob disease. Clinical and pathologic findings of
mice infected with both diseases were almost identical. This is the first
successful transmission from a typical GSS case without severe spongiform change
which suggests the possible transmissible nature of this disorder.
FFI TSE PRION IS TRANSMISSIBLE ;
Nature 376, 434 - 435 (03 August 2002); doi:10.1038/376434a0
First experimental transmission of fatal familial insomnia
Jun Tateishi*, Paul Brown‡, Tetsuyuki Kitamoto*, Zahirul M. Hoque*, Raymond
Roos§, Robert Wollman∥, Larisa Cervenàkovà ‡ & D. Carleton Gajdusek‡
* Department of Neuropathology, Neurological Institute, Kyushu University,
Fukuoka 812, Japan ‡ Laboratory of CMS Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health, Bethesda,
Mayland 20892, USA Departments of Neurology § and Pathology∥, University of
Chicago Medical Center, Chicago, Illinois 60637, USA
ORIGINALLY described by Lugaresi et al. in 1986 (ref. 1), fatal familial
insomnia (FFI) is a rare inherited neurological disease characterized by the
subacute progression of intractable insomnia and other autonomic abnormalities,
cerebellar and pyramidal signs, myoclonus and dementia; neuropathologically, the
major feature is severe neuronal loss with associated gliosis in the ventral and
mediodorsal thalamic nuclei. The disease has been related to the group of
spongiform encephalopathies by virtue of the presence of low levels of
proteinase-resistant amyloid protein (PrPres) in the brain2á¤-4, and of a
pathogenic single-allele mutation at codon 178 of the PRNP gene that encodes
PrF68 (refs 2, 5). Here we report the successful transmission of the disease to
experimental animals, placing FFI within the group of infectious cerebral
amyloidoses.
Tuesday, August 03, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the
prion protein
Monday, August 9, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the
prion protein or just more PRIONBALONEY ?
snip...see full text ;
O.K. let's compare some recent cases of this prionpathy in other countries
besides Gambetti's first 10 recently, that he claims is a spontaneous event,
from a genetic disorder, that is not genetic, but sporadic, that is related to
no animal TSE in North America, or the world. ...
Sunday, August 09, 2009
CJD...Straight talk with...James Ironside...and...Terry Singeltary...
2009
Tuesday, August 18, 2009
BSE-The Untold Story - joe gibbs and singeltary 1999 - 2009
PPS POLITICAL PRION SCIENCE $$$
Creutzfeldt-Jakob Disease Surveillance in Texas
Sunday, July 11, 2010
CJD or prion disease 2 CASES McLennan County Texas population 230,213 both
cases in their 40s
I propose that the sporadic aspect of any familial disease is from a
transmissible event, either iatrogenic, consumption, environmental, that's my
theory, hypothesis, story, whatever you want to call it, and I'm sticking to it,
until science proves to me, it's wrong. to date, science has not proven that any
of the 85%+ of all human TSE prion disease is of a sporadic or spontaneous
event, a happenstance of bad luck, just happens. that's just the
political/industrial science, nature of the beast i.e. MONEY $$$ talking, in my
opinion. ...
Friday, January 10, 2014
vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type
prion disease, what it ???
what will different strains of CWD in cervids, look like in humans
???
Wednesday, January 01, 2014
Molecular Barriers to Zoonotic Transmission of Prions
*** chronic wasting disease, there was no absolute barrier to conversion of
the human prion protein.
*** Furthermore, the form of human PrPres produced in this in vitro assay
when seeded with CWD, resembles that found in the most common human prion
disease, namely sCJD of the MM1 subtype.
Thursday, January 2, 2014
*** CWD TSE Prion in cervids to hTGmice, Heidenhain Variant
Creutzfeldt-Jacob Disease MM1 genotype, and iatrogenic CJD ???
*** The discovery of previously unrecognized prion diseases in both humans
and animals (i.e., Nor98 in small ruminants) demonstrates that the range of
prion diseases might be wider than expected and raises crucial questions about
the epidemiology and strain properties of these new forms. We are investigating
this latter issue by molecular and biological comparison of VPSPr, GSS and
Nor98.
Increased Atypical Scrapie Detections
Press reports indicate that increased surveillance is catching what
otherwise would have been unreported findings of atypical scrapie in sheep. In
2009, five new cases have been reported in Quebec, Ontario, Alberta, and
Saskatchewan. With the exception of Quebec, all cases have been diagnosed as
being the atypical form found in older animals. Canada encourages producers to
join its voluntary surveillance program in order to gain scrapie-free status.
The World Animal Health will not classify Canada as scrapie-free until no new
cases are reported for seven years. The Canadian Sheep Federation is calling on
the government to fund a wider surveillance program in order to establish the
level of prevalence prior to setting an eradication date. Besides long-term
testing, industry is calling for a compensation program for farmers who report
unusual deaths in their flocks.
Thursday, March 29, 2012
atypical Nor-98 Scrapie has spread from coast to coast in the USA 2012
NIAA Annual Conference April 11-14, 2011San Antonio, Texas
Monday, April 25, 2011
Experimental Oral Transmission of Atypical Scrapie to Sheep
Volume 17, Number 5-May 2011 However, work with transgenic mice has
demonstrated the potential susceptibility of pigs, with the disturbing finding
that the biochemical properties of the resulting PrPSc have changed on
transmission (40).
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
(hmmm, this is getting interesting now...TSS)
Sporadic CJD type 1 and atypical/ Nor98 scrapie are characterized by fine
(reticular) deposits,
see also ;
All of the Heidenhain variants were of the methionine/ methionine type 1
molecular subtype.
see full text ;
Monday, December 14, 2009
Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease
Are Encoded by Distinct Prion Types
Friday, March 09, 2012
Experimental H-type and L-type bovine spongiform encephalopathy in cattle:
observation of two clinical syndromes and diagnostic challenges
Research article
Thursday, June 23, 2011
Experimental H-type bovine spongiform encephalopathy characterized by
plaques and glial- and stellate-type prion protein deposits
P03.141
Aspects of the Cerebellar Neuropathology in Nor98
Gavier-Widén, D1; Benestad, SL2; Ottander, L1; Westergren, E1 1National
Veterinary Insitute, Sweden; 2National Veterinary Institute,
Norway Nor98 is a prion disease of old sheep and goats. This atypical form
of scrapie was first described in Norway in 1998. Several features of Nor98 were
shown to be different from classical scrapie including the distribution of
disease associated prion protein (PrPd) accumulation in the brain. The
cerebellum is generally the most affected brain area in Nor98. The study here
presented aimed at adding information on the neuropathology in the cerebellum of
Nor98 naturally affected sheep of various genotypes in Sweden and Norway. A
panel of histochemical and immunohistochemical (IHC) stainings such as IHC for
PrPd, synaptophysin, glial fibrillary acidic protein, amyloid, and cell markers
for phagocytic cells were conducted. The type of histological lesions and tissue
reactions were evaluated. The types of PrPd deposition were characterized. The
cerebellar cortex was regularly affected, even though there was a variation in
the severity of the lesions from case to case. Neuropil vacuolation was more
marked in the molecular layer, but affected also the granular cell layer. There
was a loss of granule cells. Punctate deposition of PrPd was characteristic. It
was morphologically and in distribution identical with that of synaptophysin,
suggesting that PrPd accumulates in the synaptic structures. PrPd was also
observed in the granule cell layer and in the white matter. The pathology
features of Nor98 in the cerebellum of the affected sheep showed similarities
with those of sporadic Creutzfeldt-Jakob disease in humans.
***The pathology features of Nor98 in the cerebellum of the affected sheep
showed similarities with those of sporadic Creutzfeldt-Jakob disease in
humans.
PR-26
NOR98 SHOWS MOLECULAR FEATURES REMINISCENT OF GSS
R. Nonno1, E. Esposito1, G. Vaccari1, E. Bandino2, M. Conte1, B.
Chiappini1, S. Marcon1, M. Di Bari1, S.L. Benestad3, U. Agrimi1 1 Istituto
Superiore di Sanità, Department of Food Safety and Veterinary Public Health,
Rome, Italy (romolo.nonno@iss.it); 2 Istituto Zooprofilattico della Sardegna,
Sassari, Italy; 3 National Veterinary Institute, Department of Pathology, Oslo,
Norway
Molecular variants of PrPSc are being increasingly investigated in sheep
scrapie and are generally referred to as "atypical" scrapie, as opposed to
"classical scrapie". Among the atypical group, Nor98 seems to be the best
identified. We studied the molecular properties of Italian and Norwegian Nor98
samples by WB analysis of brain homogenates, either untreated, digested with
different concentrations of proteinase K, or subjected to enzymatic
deglycosylation. The identity of PrP fragments was inferred by means of
antibodies spanning the full PrP sequence. We found that undigested brain
homogenates contain a Nor98-specific PrP fragment migrating at 11 kDa (PrP11),
truncated at both the C-terminus and the N-terminus, and not N-glycosylated.
After mild PK digestion, Nor98 displayed full-length PrP (FL-PrP) and
N-glycosylated C-terminal fragments (CTF), along with increased levels of PrP11.
Proteinase K digestion curves (0,006-6,4 mg/ml) showed that FL-PrP and CTF are
mainly digested above 0,01 mg/ml, while PrP11 is not entirely digested even at
the highest concentrations, similarly to PrP27-30 associated with classical
scrapie. Above 0,2 mg/ml PK, most Nor98 samples showed only PrP11 and a fragment
of 17 kDa with the same properties of PrP11, that was tentatively identified as
a dimer of PrP11. Detergent solubility studies showed that PrP11 is insoluble in
2% sodium laurylsorcosine and is mainly produced from detergentsoluble,
full-length PrPSc. Furthermore, among Italian scrapie isolates, we found that a
sample with molecular and pathological properties consistent with Nor98 showed
plaque-like deposits of PrPSc in the thalamus when the brain was analysed by
PrPSc immunohistochemistry. Taken together, our results show that the
distinctive pathological feature of Nor98 is a PrP fragment spanning amino acids
~ 90-155. This fragment is produced by successive N-terminal and C-terminal
cleavages from a full-length and largely detergent-soluble PrPSc, is produced in
vivo and is extremely resistant to PK digestion.
*** Intriguingly, these conclusions suggest that some pathological features
of Nor98 are reminiscent of Gerstmann-Sträussler-Scheinker disease.
119
A newly identified type of scrapie agent can naturally infect sheep with
resistant PrP genotypes
Annick Le Dur*,?, Vincent Béringue*,?, Olivier Andréoletti?, Fabienne
Reine*, Thanh Lan Laï*, Thierry Baron§, Bjørn Bratberg¶, Jean-Luc Vilotte?,
Pierre Sarradin**, Sylvie L. Benestad¶, and Hubert Laude*,?? +Author
Affiliations
*Virologie Immunologie Moléculaires and ?Génétique Biochimique et
Cytogénétique, Institut National de la Recherche Agronomique, 78350
Jouy-en-Josas, France; ?Unité Mixte de Recherche, Institut National de la
Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte
Agent Pathogène, 31066 Toulouse, France; §Agence Française de Sécurité Sanitaire
des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon,
France; **Pathologie Infectieuse et Immunologie, Institut National de la
Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology,
National Veterinary Institute, 0033 Oslo, Norway
***Edited by Stanley B. Prusiner, University of California, San Francisco,
CA (received for review March 21, 2005)
Abstract Scrapie in small ruminants belongs to transmissible spongiform
encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative
disorders that affect humans and animals and can transmit within and between
species by ingestion or inoculation. Conversion of the host-encoded prion
protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP
(PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified
surveillance of scrapie in the European Union, together with the improvement of
PrPSc detection techniques, has led to the discovery of a growing number of
so-called atypical scrapie cases. These include clinical Nor98 cases first
identified in Norwegian sheep on the basis of unusual pathological and PrPSc
molecular features and "cases" that produced discordant responses in the rapid
tests currently applied to the large-scale random screening of slaughtered or
fallen animals. Worryingly, a substantial proportion of such cases involved
sheep with PrP genotypes known until now to confer natural resistance to
conventional scrapie. Here we report that both Nor98 and discordant cases,
including three sheep homozygous for the resistant PrPARR allele (A136R154R171),
efficiently transmitted the disease to transgenic mice expressing ovine PrP, and
that they shared unique biological and biochemical features upon propagation in
mice. *** These observations support the view that a truly infectious TSE agent,
unrecognized until recently, infects sheep and goat flocks and may have
important implications in terms of scrapie control and public health.
Monday, December 1, 2008
When Atypical Scrapie cross species barriers
Authors
Andreoletti O., Herva M. H., Cassard H., Espinosa J. C., Lacroux C., Simon
S., Padilla D., Benestad S. L., Lantier F., Schelcher F., Grassi J., Torres, J.
M., UMR INRA ENVT 1225, Ecole Nationale Veterinaire de Toulouse.France;
ICISA-INlA, Madrid, Spain; CEA, IBiTec-5, DSV, CEA/Saclay, Gif sur Yvette cedex,
France; National Veterinary Institute, Postboks 750 Sentrum, 0106 Oslo, Norway,
INRA IASP, Centre INRA de Tours, 3738O Nouzilly, France.
Content
Atypical scrapie is a TSE occurring in small ruminants and harbouring
peculiar clinical, epidemiological and biochemical properties. Currently this
form of disease is identified in a large number of countries. In this study we
report the transmission of an atypical scrapie isolate through different species
barriers as modeled by transgenic mice (Tg) expressing different species PRP
sequence.
The donor isolate was collected in 1995 in a French commercial sheep flock.
inoculation into AHQ/AHQ sheep induced a disease which had all
neuro-pathological and biochemical characteristics of atypical scrapie.
Transmitted into Transgenic mice expressing either ovine or PrPc, the isolate
retained all the described characteristics of atypical scrapie.
Surprisingly the TSE agent characteristics were dramatically different
v/hen passaged into Tg bovine mice. The recovered TSE agent had biological and
biochemical characteristics similar to those of atypical BSE L in the same mouse
model. Moreover, whereas no other TSE agent than BSE were shown to transmit into
Tg porcine mice, atypical scrapie was able to develop into this model, albeit
with low attack rate on first passage.
Furthermore, after adaptation in the porcine mouse model this prion showed
similar biological and biochemical characteristics than BSE adapted to this
porcine mouse model. Altogether these data indicate.
(i) the unsuspected potential abilities of atypical scrapie to cross
species barriers
(ii) the possible capacity of this agent to acquire new characteristics
when crossing species barrier
These findings raise some interrogation on the concept of TSE strain and on
the origin of the diversity of the TSE agents and could have consequences on
field TSE control measures.
Friday, February 11, 2011
Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues
RESEARCH
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 5, May 2011
Experimental Oral Transmission of Atypical Scrapie to Sheep
Marion M. Simmons, S. Jo Moore,1 Timm Konold, Lisa Thurston, Linda A.
Terry, Leigh Thorne, Richard Lockey, Chris Vickery, Stephen A.C. Hawkins,
Melanie J. Chaplin, and John Spiropoulos
To investigate the possibility of oral transmission of atypical scrapie in
sheep and determine the distribution of infectivity in the animals’ peripheral
tissues, we challenged neonatal lambs orally with atypical scrapie; they were
then killed at 12 or 24 months. Screening test results were negative for
disease-specifi c prion protein in all but 2 recipients; they had positive
results for examination of brain, but negative for peripheral tissues.
Infectivity of brain, distal ileum, and spleen from all animals was assessed in
mouse bioassays; positive results were obtained from tissues that had negative
results on screening. These fi ndings demonstrate that atypical scrapie can be
transmitted orally and indicate that it has the potential for natural
transmission and iatrogenic spread through animal feed. Detection of infectivity
in tissues negative by current surveillance methods indicates that diagnostic
sensitivity is suboptimal for atypical scrapie, and potentially infectious
material may be able to pass into the human food chain.
SNIP...
Although we do not have epidemiologic evidence that supports the effi cient
spread of disease in the fi eld, these data imply that disease is potentially
transmissible under fi eld situations and that spread through animal feed may be
possible if the current feed restrictions were to be relaxed. Additionally,
almost no data are available on the potential for atypical scrapie to transmit
to other food animal species, certainly by the oral route. However, work with
transgenic mice has demonstrated the potential susceptibility of pigs, with the
disturbing fi nding that the biochemical properties of the resulting PrPSc have
changed on transmission (40). The implications of this observation for
subsequent transmission and host target range are currently unknown.
How reassuring is this absence of detectable PrPSc from a public health
perspective? The bioassays performed in this study are not titrations, so the
infectious load of the positive gut tissues cannot be quantifi ed, although
infectivity has been shown unequivocally. No experimental data are currently
available on the zoonotic potential of atypical scrapie, either through
experimental challenge of humanized mice or any meaningful epidemiologic
correlation with human forms of TSE. However, the detection of infectivity in
the distal ileum of animals as young as 12 months, in which all the tissues
tested were negative for PrPSc by the currently available screening and confi
rmatory diagnostic tests, indicates that the diagnostic sensitivity of current
surveillance methods is suboptimal for detecting atypical scrapie and that
potentially infectious material may be able to pass into the human food chain
undetected.
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 5, May 2011
Identifying Variation in the U.S. Bovine Prion Gene
Bovine spongiform encephalopathy—BSE, or mad cow disease—is a serious
threat to the U.S. beef industry.
While the first confirmed case of BSE on U.S. soil in December 2003 had
little effect on domestic consumption, it carved into our international beef
sales. According to USDA’s Economic Research Service, the United States exported
only $552 million worth of beef in 2004—down from $2.6 billion in 2002 and $3.1
billion in 2003—a reduction due, in part, to the BSE case.
Are some cattle more susceptible to BSE? Is there a genetic component
involved?
To address these and other questions, ARS scientists at the U.S. Meat
Animal Research Center (USMARC) at Clay Center, Nebraska, have sequenced the
bovine prion gene, PRNP, in 192 cattle representing 16 beef and 5 dairy breeds
common in the United States. This work was partially funded by a grant from
USDA’s Cooperative State Research, Education, and Extension Service.
Prions are proteins that occur naturally in mammals. BSE is a fatal
neurological disorder characterized by irregularly folded prions. Much is
unknown about the disease, but scientists recognize a correlation between
variations in the PRNP gene in some mammals and susceptibility to transmissible
spongiform encephalopathies, such as scrapie in sheep.
“Evidence indicates that this could also be true in cattle,” says molecular
biologist Mike Clawson. He is among the USMARC scientists examining PRNP
variation to learn if and how different forms, or alleles, of the prion gene
correlate with BSE susceptibility.
A thorough characterization of PRNP variation in a U.S. cattle population
will provide a reference framework for researchers to use in analyzing PRNP
sequences from cattle afflicted with BSE.
From the 192 PRNP genes sequenced, Clawson and his colleagues have
identified 388 variations, or polymorphisms, of which 287 were previously
unknown. Some of these polymorphisms may influence BSE susceptibility in cattle,
he says. Ongoing studies with European collaborators are testing the newly
identified variants for association with BSE. If these studies show some cattle
to be genetically less susceptible to the disease, this information could shed
light on BSE’s transmission and development.
The United States has had only three confirmed cases of BSE. Laboratory
tests showed that the second and third of these appear to differ significantly
from the first case, says Clawson.
“By comparing the PRNP sequence from BSE-infected cattle to healthy cattle,
we may be able to identify genetic markers in the prion gene that predict BSE
susceptibility,” he says.
In addition to PRNP, the team is currently sequencing several genes closely
related to it. These too will be tested for their association with BSE.
“The prevalence of BSE in the United States is extremely low and is
declining worldwide,” Clawson says. “Well-characterized genetic markers that
correlate to resistance could improve our understanding of the disease and
prepare the cattle industry to respond if another prion disease arises in the
future.”—By Laura McGinnis, Agricultural Research Service Information
Staff.
This research is part of Animal Health, an ARS National Program (#103)
described on the World Wide Web at www.nps.ars.usda.gov.
Michael L. Clawson is at the USDA-ARS Roman L. Hruska U.S. Meat Animal
Research Center, P.O. Box 166, Clay Center, NE 68933; phone (402) 762-4342, fax
(402) 762-4375.
"Identifying Variation in the U.S. Bovine Prion Gene" was published in the
January 2007 issue of Agricultural Research magazine.
Research Project: Susceptibility of Cattle with the E211k Prnp Allele to
Bse
Location: Virus and Prion Research Unit
Project Number: 3625-32000-086-14 Project Type: Specific Cooperative
Agreement
Start Date: Aug 14, 2008 End Date: Jul 31, 2013
Objective:
The objective of this cooperative research project is to investigate the
influence of the bovine Prnp gene polymorphisms, E211K, on the susceptibility to
BSE. Specifically, the research project will provide 134 embryos that will be
used to generate approximately 62 animals, 31 of which will contain the rare
allele for the purposes BSE research. This ongoing SCA with Iowa State
University to produce cattle with the E211K Prnp allele for BSE research has
resulted in an E211/K211 heterozygous bull. We are now in the unique position to
extend our research on this allele to include animals homozygous for K at
position 211. Based upon our understanding of this novel polymorphism one would
predict homozygotes would have a more rapid onset of clinical signs associated
with genetic BSE than heterozygotes.
Approach:
To achieve the research goals it is imperative to increase the number of
animals available to study this Prnp polymorphism. One female calf of the 2006
BSE case was identified and carries the E211K allele. The specific objectives
are to be accomplished through the production of multiple offspring from this
E211K heifer through superovulation and embryo transfer. Approximately 50% of
the offspring will be heterozygous for the E211K polymorphism while the others
will serve as genetically matched non-E211K controls. Collection of semen from
an E211K heterozygous bull will allow creation of E211K homozygotes. To protect
this unique resource immediate collection of embryos is necessary. The initial
goal is to harvest 134 embryos that should result in approximately 62
pregnancies (half of which will carry the E211K polymorphism) for immediate use
in the studies to amplify the E211K material, test for genetic susceptibility to
TSE, and develop a breeding group to produce calves for transmissibility
studies. To achieve the goal of understanding the role of the E211K polymorphism
with regard to genetic BSE we have utilized superovulation and embryo transfer
obtaining a E211/K211 containing bull. We are now in a position to collect semen
from the E211/K211 heterozygous bull to create K211/K211 homozygotes. To
accomplish this goal we plan to collect semen from this bull and through
artificial insemination using semen from the E211/K211 bull with superovulation
and embryo transplantation using other E211/K211 heterzygotes generate 30-40
embryos resulting in 15-20 pregnancies yielding approximately 5 K211/K211
homozygous animals and 10 E211/K211 heterozyous animals as well as 5 E211/E211
homozygous controls.
Subject: Identifying Variation in the U.S. Bovine Prion Gene Date: January
22, 2007 at 8:32 am PST
Identifying Variation in the U.S. Bovine Prion Gene By Laura McGinnis
January 22, 2007 Do genes affect bovine spongiform encephalopathy?also known as
BSE, or "mad cow" disease? Are some cattle more susceptible than others?
To address these and other questions, Agricultural Research Service (ARS)
scientists at the U.S. Meat Animal Research Center in Clay Center, Neb., have
sequenced the bovine prion gene (PRNP) in 192 cattle that represent 16 beef and
five dairy breeds common in the United States.
This work, partially funded by a grant from the U.S. Department of
Agriculture's Cooperative State Research, Education and Extension Service, is
expanding the understanding of how the disease works.
BSE is a fatal neurological disorder characterized by prions?proteins that
occur naturally in mammals?that fold irregularly. Molecular biologist Mike
Clawson and his Clay Center colleagues are examining PRNP variation in order to
learn if and how prions correlate with BSE susceptibility.
From the 192 PRNP sequences, Clawson and his colleagues have identified 388
variations, or polymorphisms, 287 of which were previously unknown. Some of
these polymorphisms may influence BSE susceptibility in cattle.
Comparing PRNP sequences from infected and healthy cattle may enable
researchers to identify genetic markers in the prion gene that predict BSE
susceptibility. In addition to PRNP, the team is currently sequencing several
closely related genes, which will also be tested for their association with
BSE.
The prevalence of BSE in the United States is extremely low, but this
research could improve understanding of the disease and prepare the cattle
industry to respond if another prion disease should arise in the future.
Identifying Variation in the U.S. Bovine Prion Gene
Bovine spongiform encephalopathy (BSE, or mad cow disease) is a serious
threat to the U.S. beef industry.
While the first confirmed case of BSE on U.S. soil in December 2003 had
little effect on domestic consumption, it carved into our international beef
sales. According to USDAs Economic Research Service, the United States exported
only $552 million worth of beef in 2004 down from $2.6 billion in 2002 and $3.1
billion in 2003 a reduction due, in part, to the BSE case.
Are some cattle more susceptible to BSE? Is there a genetic component
involved?
To address these and other questions, ARS scientists at the U.S. Meat
Animal Research Center (USMARC) at Clay Center, Nebraska, have sequenced the
bovine prion gene, PRNP, in 192 cattle representing 16 beef and 5 dairy breeds
common in the United States. This work was partially funded by a grant from
USDA?s Cooperative State Research, Education, and Extension Service.
Prions are proteins that occur naturally in mammals. BSE is a fatal
neurological disorder characterized by irregularly folded prions. Much is
unknown about the disease, but scientists recognize a correlation between
variations in the PRNP gene in some mammals and susceptibility to transmissible
spongiform encephalopathies, such as scrapie in sheep.
Evidence indicates that this could also be true in cattle, says molecular
biologist Mike Clawson. He is among the USMARC scientists examining PRNP
variation to learn if and how different forms, or alleles, of the prion gene
correlate with BSE susceptibility.
A thorough characterization of PRNP variation in a U.S. cattle population
will provide a reference framework for researchers to use in analyzing PRNP
sequences from cattle afflicted with BSE.
From the 192 PRNP genes sequenced, Clawson and his colleagues have
identified 388 variations, or polymorphisms, of which 287 were previously
unknown. Some of these polymorphisms may influence BSE susceptibility in cattle,
he says. Ongoing studies with European collaborators are testing the newly
identified variants for association with BSE. If these studies show some cattle
to be genetically less susceptible to the disease, this information could shed
light on BSEs transmission and development.
The United States has had only three confirmed cases of BSE. Laboratory
tests showed that the second and third of these appear to differ significantly
from the first case, says Clawson.
By comparing the PRNP sequence from BSE-infected cattle to healthy cattle,
we may be able to identify genetic markers in the prion gene that predict BSE
susceptibility, he says.
In addition to PRNP, the team is currently sequencing several genes closely
related to it. These too will be tested for their association with BSE.
The prevalence of BSE in the United States is extremely low and is
declining worldwide, Clawson says. Well-characterized genetic markers that
correlate to resistance could improve our understanding of the disease and
prepare the cattle industry to respond if another prion disease arises in the
future. By Laura McGinnis, Agricultural Research Service Information
Staff.
This research is part of Animal Health, an ARS National Program (#103)
described on the World Wide Web at www.nps.ars.usda.gov.
Michael L. Clawson is at the USDA-ARS Roman L. Hruska U.S. Meat Animal
Research Center, P.O. Box 166, Clay Center, NE 68933; phone (402) 762-4342, fax
(402) 762-4375.
Title: Prion gene haplotypes of U.S. cattle
Authors
Clawson, Michael - mike Heaton, Michael - mike Keele, John Smith, Timothy -
tim Harhay, Gregory Laegreid, William - will
Submitted to: BioMed Central (BMC) Genetics Publication Type: Peer Reviewed
Journal Publication Acceptance Date: October 24, 2006 Publication Date: November
8, 2006 Reprint URL: http://www.biomedcentral.com/1471-2156/7/51
Citation: Clawson, M.L., Heaton, M.P., Keele, J.W., Smith, T.P., Harhay, G.P.,
Laegreid, W.W. 2006. Prion gene haplotypes of U.S. cattle. BioMed Central (BMC)
Genetics. 7:51.
Interpretive Summary: Transmissible spongiform encephalopathies (TSEs) are
fatal neurological disorders that are characterized by abnormal deposits of the
prion protein. TSEs have been identified in cats, cattle, deer, elk, humans,
mink, moose, and sheep. The cattle TSE, bovine spongiform encephalopathy (BSE)
is also known as mad cow disease. BSE is the probable cause of the human TSE
variant Creutzfeldt-Jakob disease, transmitted from cattle to people via the
food chain. Sequence variation in the prion gene correlates with TSE progression
in humans, sheep, and mice. Additionally, there is evidence that bovine PRNP
variation correlates with BSE progression. In this study, 25.2 kb of PRNP was
sequenced from the promoter region through the three prime untranslated region
in 192 U.S. cattle (16 beef, five dairy breeds). Three hundred and eighty eight
polymorphisms were observed, of which 287 have not been previously reported. A
subset of polymorphisms that efficiently tag genetic variation in U.S. cattle
was identified. The results of this study provide a reference framework for
accurate and comprehensive evaluation of prion gene variation and its
relationship to BSE. Technical Abstract: Background: Bovine spongiform
encephalopathy (BSE) is a fatal neurological disorder characterized by abnormal
deposits of a protease-resistant isoform of the prion protein. Characterizing
linkage disequilibrium (LD) and haplotype networks within the bovine prion gene
(PRNP) is important for 1) testing rare or common PRNP variation for an
association with BSE and 2) interpreting any association of PRNP alleles with
BSE susceptibility. The objective of this study was to identify polymorphisms
and haplotypes within PRNP from the promoter region through the 3'UTR in a
diverse sample of U.S. cattle genomes. Results: A 25.2-kb genomic region
containing PRNP was sequenced from 192 diverse U.S. beef and dairy cattle.
Sequence analyses identified 388 total polymorphisms, of which 287 have not
previously been reported. The polymorphism alleles define PRNP by regions of
high and low LD. High LD is present between alleles in the promoter region
through exon 2 (6.7 kb). PRNP alleles within the majority of intron 2, the
entire coding sequence and the untranslated region of exon 3 are in low LD (18.0
kb). Two haplotype networks, one representing the region of high LD and the
other the region of low LD yielded nineteen different combinations that
represent haplotypes spanning PRNP. The haplotype combinations are tagged by 19
polymorphisms (htSNPS) which characterize variation within and across
PRNP.
Conclusion: The number of polymorphisms in the prion gene region of U.S.
cattle is nearly four times greater than previously described. These
polymorphisms define PRNP haplotypes that may influence BSE susceptibility in
cattle.
Title: Frequencies of polymorphisms associated with BSE resistance differ
significantly between Bos taurus, Bos indicus, and composite cattle
Authors
BRUNELLE, BRIAN GREENLEE, JUSTIN Seabury, Christopher - TEXAS A&M
UNIVERSITY Brown Ii, Charles - ABS GLOBAL NICHOLSON, ERIC
Submitted to: BioMed Central (BMC) Veterinary Research Publication Type:
Peer Reviewed Journal Publication Acceptance Date: August 22, 2008 Publication
Date: August 22, 2008 Citation: Brunelle, B.W., Greenlee, J.J., Seabury, C.M.,
Brown II, C.E., Nicholson, E.M. 2008. Frequencies of Polymorphisms Associated
with BSE Resistance Differ Significantly Between Bos taurus, Bos indicus, and
Composite Cattle. BioMed Central (BMC) Veterinary Research. 4(1):36. Available:
http://www.biomedcentral.com/1746-6148/4/36.
Interpretive Summary: Bovine spongiform encephalopathy (BSE) is a
neurodegenerative prion disease of cattle. There are three host factors related
to the host prion protein known to influence susceptibility or resistance to
BSE: single amino acid changes in the prion protein, repeat regions within the
prion protein, and expression levels of the prion protein. These factors have
been well documented in breeds of Bos taurus cattle, but there is little-to-no
data on these factors in Bos indicus purebred or Bos indicus x Bos taurus
crossbred cattle. Since Bos indicus cattle contribute to the U.S. cattle
population, we wanted to determine the frequency of the host factors associated
with BSE susceptibility. We studied 58 Bos indicus purebred and 38 Bos indicus x
Bos taurus crossbred cattle. The only differences between Bos indicus and Bos
taurus cattle were in two factors associated with prion protein expression
levels. It was observed that Bos indicus cattle had a much higher frequency of
one factor associated with resistance to BSE compared to Bos taurus cattle,
while the second factor associated with resistance to BSE was much lower in Bos
indicus cattle compared to Bos taurus cattle. This data is useful in determining
the relative risk of BSE in Bos indicus cattle based upon these factors.
Technical Abstract: Transmissible spongiform encephalopathies (TSEs) are
neurodegenerative diseases that affect several mammalian species. At least three
factors related to the host prion protein are known to modulate susceptibility
or resistance to a TSE: amino acid sequence, atypical number of octapeptide
repeats, and expression level. These factors have been extensively studied in
breeds of Bos taurus cattle in relation to bovine spongiform encephalopathy
(BSE). However, little is currently known about these factors in Bos indicus
purebred or B. indicus x B. taurus crossbred cattle. The goal of our study was
to establish the frequency of markers associated with enhanced susceptibility or
resistance to BSE in B. indicus purebred and crossbred cattle.
18 January 2007 - Draft minutes of the SEAC 95 meeting (426 KB) held on 7
December 2006 are now available.
snip...
ITEM 9 - ANY OTHER BUSINESS
snip...
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
64. A member noted that at the recent Neuroprion meeting, a study was
presented showing that in transgenic mice BSE passaged in sheep may be more
virulent and infectious to a wider range of species than bovine derived BSE.
Other work presented suggested that BSE and bovine amyloidotic spongiform
encephalopathy (BASE) MAY BE RELATED. A mutation had been identified in the
prion protein gene in an AMERICAN BASE CASE THAT WAS SIMILAR IN NATURE TO A
MUTATION FOUND IN CASES OF SPORADIC CJD. A study also demonstrated that in a
mouse model it was possible to alleviate the pathological changes of prion
disease by suppressing expression of the prion protein gene after
infection.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
NOW PLEASE GO BACK AND READ THAT SECOND PARAGRAPH AGAIN.....TSS
PLEASE READ FULL TEXT ;
Discussion
This study assessed the prevalence of specific BSE-associated factors in B.
indicus purebred and composite cattle, which were then compared to frequencies
observed in B. taurus cattle. Through PRNP sequence analysis, we surveyed cattle
for the presence of an E211K amino acid replacement, as well as the presence of
7 or more octapeptide repeats. In addition, we determined the frequencies of the
23-bp and 12-bp indel regions associated with bovine PRNP transcriptional
regulation.
None of the PRNP alleles for the B. indicus samples evaluated in this study
exhibited an E211K amino acid replacement or any novel coding region
polymorphism. To date, the E211K change has been reported in only two bovine
samples, the 2006 Alabama atypical BSE case [7] and its only known living
offspring [8]. The affected animal was a composite (B. taurus × B. indicus), but
because no parental information is currently available, it is unknown whether
the corresponding nucleotide change was inherited or the result of spontaneous
mutation. If it was inherited, then the E211K allele may have originated in
either a B. taurus ancestor or a B. indicus ancestor. Unfortunately, the data
presented here cannot facilitate a species level assignment, as the PRNP coding
sequence of the 2006 Alabama case did not possess any species-specific
polymorphisms. This particular animal was determined to possess one haplotype
with a 23 and 12-bp insertion, and the other with a 23 and 12-bp deletion [27].
These 2 haplotypes occur in 92% of B. taurus, but only in 25% B. indicus cattle
(Table ?(Table1),1), as estimated by our analyses. Unless more information
becomes available, it cannot be determined where the E211K replacement may have
originated.
No B. indicus sample had an octapeptide region containing more than 6
repeats. Notably, humans are the only TSE-susceptible mammal besides the Brown
Swiss breed of B. taurus cattle for which additional octapeptide repeats have
been observed. Interestingly, a transgenic mouse model expressing bovine PrPC
with 1 extra repeat was more susceptible to BSE challenge than a transgenic
mouse with the normal number of repeats, but did not develop a spontaneous prion
disease [14]. However, a transgenic mouse expressing a bovine PRNP gene encoding
4 additional repeats did in fact develop a spontaneous prion disease [15]. While
cattle with 1 additional octapeptide repeat may have an enhanced risk for
classical BSE only if exposed to infected material, the appearance of PRNP genes
encoding extra octapeptide repeats in any cattle breed may be cause for
concern.
The incidence of E211K as well as octapeptide regions with 7 repeats among
cattle does not provide a species-level explanation for potential differences in
susceptibility to BSE among B. taurus and B. indicus cattle. Therefore, only the
23-bp and 12-bp indel regions seem pertinent in these populations because both
of these bovine PRNP sequence regions have been shown to influence transcription
levels of PrPC. The B. indicus purebred and composite cattle had a very low
frequency of the 23-bp insertion as compared to B. taurus, while only B. indicus
purebred cattle had a high frequency of the 12-bp insertion. To date, no
consensus has emerged regarding whether one of these bovine PRNP regions is more
influential than the other with respect to classical BSE resistance in cattle.
Originally, only the 23-bp region was found to be significantly associated with
(classical) BSE resistance [26]. Using a reporter gene assay, it was later
concluded that the 23-bp indel region was the most relevant locus, as the only
constructs that lowered expression levels were those containing the 23-bp
insertion [25]. In contrast, other reports indicate the 12-bp indel is more
relevant both statistically [24] and in a reporter gene assay [30]. The
discrepancy between the significance of these two regions with respect to
resistance or susceptibility to classical BSE may be influenced by 3 or more
factors. First, the 23-bp and 12-bp regions are physically linked (~2-Kbp
apart). Therefore, recombination is most likely rare given the small distance
separating the two indel polymorphisms. Moreover, high levels of linkage
disequilibrium have been detected for genetic variation within the bovine PRNP
promoter and intron 1 [31]. Secondarily, the 23-bp insertion and 12-bp deletion
haplotype is absent among cattle surveyed to date, thereby creating an
equal-to-greater overall frequency of 12-bp insertions as compared to the
frequency spectrum of 23-bp insertions. More specifically, twice as many
haplotypes (n = 12) contribute to the overall frequency of the 12-bp intron 1
insertion as those contributing to the frequency of the 23-bp insertion (n = 6;
Table ?Table2).2). This may inevitably bias indel association studies. Lastly,
species specific allelic variation associated with the genetic backgrounds of B.
taurus and B. indicus may differentially interact with the 23-bp promoter and
12-bp intron 1 PRNP polymorphisms, perhaps making each polymorphism more or less
relevant in a particular bovine species. On the basis of indel genotype alone,
if it is ultimately concluded that the 23-bp insertion has a greater influence
than the 12-bp insertion with respect to resistance to classical BSE in cattle
following exposure to infected material, B. indicus purebred and composite
cattle would be at greater risk than B. taurus cattle. Conversely, if the 12-bp
insertion were to modulate a greater level of resistance to BSE, then B. indicus
cattle would be at a lower risk than B. taurus and composite cattle.
Other Sections?
Conclusion
We determined the frequencies of known genetic factors associated with
differential susceptibility to BSE in B. indicus purebred and B. indicus × B.
taurus composite cattle, as compared to B. taurus purebred cattle. No deviations
from the expected numbers of octapeptide repeats were detected for B. indicus
purebred and composite cattle. Likewise, the E211K substitution was not detected
within the PRNP coding sequences for cattle investigated herein. However, a
significant difference was detected for a comparison of the 23-bp and 12-bp
indel genotype frequencies between B. indicus and B. taurus cattle. The origin
of this result could be attributed to significant differences in haplotype
frequencies among B. indicus, B. taurus, and composite cattle. Currently, it is
unknown which bovine PRNP region (23-bp promoter; 12-bp intron 1), if either,
may be more important with respect to differential susceptibility to classical
BSE in cattle following exposure to the etiologic agent. Should either the 23-bp
promoter region or the 12-bp intron 1 region of the bovine PRNP prove more
biologically relevant to the manifestation of disease, substantial heritable
differences in overall susceptibility or resistance to classical BSE may exist
between B. indicus and B. taurus cattle.
let's take a closer look at this new prionpathy or prionopathy, and then
let's look at the g-h-BSEalabama mad cow.
This new prionopathy in humans? the genetic makeup is IDENTICAL to the
g-h-BSEalabama mad cow, the only _documented_ mad cow in the world to date like
this, ......wait, it get's better. this new prionpathy is killing young and old
humans, with LONG DURATION from onset of symptoms to death, and the symptoms are
very similar to nvCJD victims, OH, and the plaques are very similar in some
cases too, bbbut, it's not related to the g-h-BSEalabama cow, WAIT NOW, it gets
even better, the new human prionpathy that they claim is a genetic TSE, has no
relation to any gene mutation in that family. daaa, ya think it could be related
to that mad cow with the same genetic make-up ??? there were literally tons and
tons of banned mad cow protein in Alabama in commerce, and none of it
transmitted to cows, and the cows to humans there from ??? r i g h t $$$
ALABAMA MAD COW g-h-BSEalabama
In this study, we identified a novel mutation in the bovine prion protein
gene (Prnp), called E211K, of a confirmed BSE positive cow from Alabama, United
States of America. This mutation is identical to the E200K pathogenic mutation
found in humans with a genetic form of CJD. This finding represents the first
report of a confirmed case of BSE with a potential pathogenic mutation within
the bovine Prnp gene. We hypothesize that the bovine Prnp E211K mutation most
likely has caused BSE in "the approximately 10-year-old cow" carrying the E221K
mutation.
her healthy calf also carried the mutation (J. A. Richt and S. M. Hall PLoS
Pathog. 4, e1000156; 2008).
This raises the possibility that the disease could occasionally be genetic
in origin. Indeed, the report of the UK BSE Inquiry in 2000 suggested that the
UK epidemic had most likely originated from such a mutation and argued against
the scrapierelated assumption. Such rare potential pathogenic PRNP mutations
could occur in countries at present considered to be free of BSE, such as
Australia and New Zealand. So it is important to maintain strict surveillance
for BSE in cattle, with rigorous enforcement of the ruminant feed ban (many
countries still feed ruminant proteins to pigs). Removal of specified risk
material, such as brain and spinal cord, from cattle at slaughter prevents
infected material from entering the human food chain. Routine genetic screening
of cattle for PRNP mutations, which is now available, could provide additional
data on the risk to the public. Because the point mutation identified in the
Alabama animals is identical to that responsible for the commonest type of
familial (genetic) CJD in humans, it is possible that the resulting infective
prion protein might cross the bovine–human species barrier more easily. Patients
with vCJD continue to be identified. The fact that this is happening less often
should not lead to relaxation of the controls necessary to prevent future
outbreaks.
Malcolm A. Ferguson-Smith Cambridge University Department of Veterinary
Medicine, Madingley Road, Cambridge CB3 0ES, UK e-mail: maf12@cam.ac.uk Jürgen
A. Richt College of Veterinary Medicine, Kansas State University, K224B Mosier
Hall, Manhattan, Kansas 66506-5601, USA
NATURE|Vol 457|26 February 2009
Saturday, August 14, 2010
BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and
VPSPr PRIONPATHY
(see mad cow feed in COMMERCE IN ALABAMA...TSS)
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
1: J Infect Dis 1980 Aug;142(2):205-8
Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to
nonhuman primates.
Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.
Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep
and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were
exposed to the infectious agents only by their nonforced consumption of known
infectious tissues. The asymptomatic incubation period in the one monkey exposed
to the virus of kuru was 36 months; that in the two monkeys exposed to the virus
of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the
two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively.
Careful physical examination of the buccal cavities of all of the monkeys failed
to reveal signs or oral lesions. One additional monkey similarly exposed to kuru
has remained asymptomatic during the 39 months that it has been under
observation.
snip...
The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie
by natural feeding to squirrel monkeys that we have reported provides further
grounds for concern that scrapie-infected meat may occasionally give rise in
humans to Creutzfeldt-Jakob disease.
PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Recently the question has again been brought up as to whether scrapie is
transmissible to man. This has followed reports that the disease has been
transmitted to primates. One particularly lurid speculation (Gajdusek 1977)
conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and
transmissible encephalopathy of mink are varieties of a single "virus". The U.S.
Department of Agriculture concluded that it could "no longer justify or permit
scrapie-blood line and scrapie-exposed sheep and goats to be processed for human
or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is
emphasised by the finding that some strains of scrapie produce lesions identical
to the once which characterise the human dementias"
Whether true or not. the hypothesis that these agents might be
transmissible to man raises two considerations. First, the safety of laboratory
personnel requires prompt attention. Second, action such as the "scorched meat"
policy of USDA makes the solution of the acrapie problem urgent if the sheep
industry is not to suffer grievously.
snip...
76/10.12/4.6
Nature. 1972 Mar 10;236(5341):73-4.
Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).
Gibbs CJ Jr, Gajdusek DC.
Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0
Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)
C. J. GIBBS jun. & D. C. GAJDUSEK
National Institute of Neurological Diseases and Stroke, National Institutes
of Health, Bethesda, Maryland
SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey
(Macaca fascicularis) with an incubation period of more than 5 yr from the time
of intracerebral inoculation of scrapie-infected mouse brain. The animal
developed a chronic central nervous system degeneration, with ataxia, tremor and
myoclonus with associated severe scrapie-like pathology of intensive astroglial
hypertrophy and proliferation, neuronal vacuolation and status spongiosus of
grey matter. The strain of scrapie virus used was the eighth passage in Swiss
mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral
passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton,
Berkshire).
Friday, August 16, 2013
*** Creutzfeldt-Jakob disease (CJD) biannual update August 2013 U.K. and Contaminated blood products induce a highly atypical prion disease devoid of PrPres in primates http://creutzfeldt-jakob-disease.blogspot.com/2013/08/creutzfeldt-jakob-disease-cjd-biannual.html
WHAT about the sporadic CJD TSE proteins ?
WE now know that some cases of sporadic CJD are linked to atypical BSE and atypical Scrapie, so why are not MORE concerned about the sporadic CJD, and all it’s sub-types $$$
Creutzfeldt-Jakob Disease CJD cases rising North America updated report August 2013
*** Creutzfeldt-Jakob Disease CJD cases rising North America with Canada seeing an extreme increase of 48% between 2008 and 2010 *** http://creutzfeldt-jakob-disease.blogspot.com/2013/08/creutzfeldt-jakob-disease-cjd-cases.html
Sunday, October 13, 2013
*** CJD TSE Prion Disease Cases in Texas by Year, 2003-2012 http://creutzfeldt-jakob-disease.blogspot.com/2013/10/cjd-tse-prion-disease-cases-in-texas-by.html
kind regards, terry
