Transmission Characteristics of Variably Protease-Sensitive Prionopathy
Silvio Notari,1 Xiangzhu Xiao,1 Juan Carlos Espinosa, Yvonne Cohen, Liuting
Qing, Patricia Aguilar-Calvo, Diane Kofskey, Ignazio Cali, Laura Cracco,
Qingzhong Kong, Juan Maria Torres, Wenquan Zou, and Pierluigi Gambetti
Variably protease-sensitive prionopathy (VPSPr), a recently identified and
seemingly sporadic human prion disease, is distinct from Creutzfeldt-Jakob
disease (CJD) but shares features of Gerstmann-Sträussler-Scheinker disease
(GSS). However, contrary to exclusively inherited GSS, no prion protein (PrP)
gene variations have been detected in VPSPr, suggesting that VPSPr might be the
long-sought sporadic form of GSS. The VPSPr atypical features raised the issue
of transmissibility, a prototypical property of prion diseases. We inoculated
VPSPr brain homogenate into transgenic mice expressing various levels of human
PrP (PrPC). On first passage, 54% of challenged mice showed histopathologic
lesions, and 34% harbored abnormal PrP similar to that of VPSPr. Surprisingly,
no prion disease was detected on second passage. We concluded that VPSPr is
transmissible; thus, it is an authentic prion disease. However, we speculate
that normal human PrPC is not an efficient conversion substrate (or mouse brain
not a favorable environment) and therefore cannot sustain replication beyond the
first passage.
Prion diseases include a variety of animal and human conditions that might
be sporadic, inherited, or acquired by infection. Despite this diversity, most
prion diseases are thought to share the same pathogenetic mechanism whereby the
cellular prion protein (PrPC) is templated into an abnormal and pathogenic
conformer, commonly identified as scrapie PrP (PrPSc) (1). Therefore, conversion
by templating is the basic mechanism that causes disease and sustains disease
transmission among humans (2). However, data have shown that propagation,
disease manifestation, and transmissibility might occur separately in various
ways (3,4).
The phenotype of human prion diseases is highly heterogeneous. This
characteristic is largely due to the variable genotype at codon 129, the site of
a methionine/ valine (MV) polymorphism in the human PrP gene, and the molecular
characteristics of the associated PrPSc (5). A further major distinction that
has been applied to human prion diseases for years is based on the experimental
transmissibility of these diseases to hosts thought to be permissive for
exogenous human PrPSc (6). Based on this principle, the sporadic form of
Creutzfeldt-Jakob disease (sCJD) belongs to the transmissible disease group,
whereas most of the Gerstmann-Sträussler-Scheinker diseases (GSS), a group
comprising exclusively inherited forms, were considered difficult to transmit or
not transmissible (7–10). However, an increasing number of findings have
challenged this distinction. Replication of infectious PrPSc occurs in the
absence of clinical signs in the host, or even in the absence of detectable
disease, by histologic and Western blot (WB) examinations. Yet, infectivity can
be demonstrated in subsequent passages to more susceptible hosts (9,11,12).
Finally, disease transmissibility has recently been demonstrated for a subtype
of GSS previously thought to be nontransmissible (8,10,13).
In 2008 and 2010, we introduced a novel human prion disease, presumably
sporadic, that we named variably protease-sensitive prionopathy (VPSPr) (14–16).
VPSPr differs from sCJD in several aspects. The clinical presentation and the
frequent slow progression evoke the features of atypical dementias, such as
frontotemporal dementia, diffuse Lewy body disease, or normal pressure
hydrocephalus (17). The flocculent PrP immunostaining pattern, which includes
the frequent presence of PrP peculiar amyloid plaques, differs from those of
other sporadic prion diseases. However, the most distinctive VPSPr feature rests
on the characteristics of the associated PrPSc, especially the electrophoretic
profile and resistance to the commonly used protease, such as proteinase K (PK)
(14,15,17). VPSPr-associated, PK-resistant PrPSc (resPrPSc) forms a distinctive
5-band electrophoretic profile, comprising various fragments truncated at the N
terminal and at least 1 fragment truncated at both N and C terminals, which
consequently lacks the GPI (glycosylphosphatidylinositol) anchor (14).
Furthermore, the N-truncated fragments do not include the diglycosylated PrPSc
isoforms but only 1 of 2 monoglycosylated and the unglycosylated isoforms (18),
and upon cleavage of the glycans, these fragments form 3 PK-resistant WB bands
in VPSPr preparations. In contrast, the electrophoretic profile of sCJD resPrPSc
is characterized by 3 bands, including diglycosylated, 2 monoglycosylated, and
unglycosylated isoform, all of which harbor the GPI anchor and form only 1 band
after glycan removal (19). However, VPSPr also occasionally displays small
amounts of typical 3 electrophoretic band–forming resPrPSc on WB of basal
ganglia and other deep cerebral structures (14). On the whole, the VPSPr 5-band
ladder profile is more akin to the electrophoretic profile of PrPSc in most GSS
subtypes, although contrary to GSS, no mutation in the PrP gene open reading
frame has been observed in VPSPr (14–16). Given this similarity, Zou et al.
hypothesized that VPSPr is the sporadic form of GSS (15). Like sCJD, VPSPr
affects persons harboring each of 3 PrPC 129 genotypes: methionine and valine
homozygosity (MM, VV) and MV heterozygosity. The 3 genotypic subtypes of VPSPr
differ slightly in clinical presentation, duration, histopathologic features,
and PK resistance of the PrPSc (15).
The similarity in the PrPSc electrophoretic profiles with GSS, which was
regarded as not transmissible, called into question the transmissibility of
VPSPr and prompted use of the term prionopathy rather than prion disease. The
present study addresses this issue. Transgenic (Tg) mice expressing various
levels of human PrPC harboring methionine (M) or valine (V) at position 129
underwent intracranial inoculation with brain homogenates (BH) from several
human case-patients with VPSPr associated with each of the three 129 genotypes
(15). Surprisingly, VPSPr was transmitted as an asymptomatic disease
characterized by focal accumulation of VPSPr-like PrPSc in the first passage,
but no prion disease could be demonstrated in the second passage.
snip...
Discussion
The experiments reported here, which probed transmissibility of VPSPr to Tg
mice expressing human PrPC, yielded puzzling results. On first passage, all
hosts remained asymptomatic, but 54% showed focal deposition of PrPSc in the
form of prion plaques by immunohistochemical analysis. In 34% of animals, small
amounts of resPrPSc were demonstrated by WB (Figures 1, 3). The PrPSc recovered
from affected mice recapitulated the electrophoretic profile and
immunoreactivity features of the VPSPr-129VV PrPSc, even after removal of the
sugar moiety. However, mouse PrPSc was apparently more PK-resistant than the
PrPSc from VPSPr-129VV case-patients (Figure 3) (15). In contrast, on second
passage, all Tg mice were negative at clinical and histopathologic examinations
and harbored no PrPSc that could be definitely identified by WB, even up to 800
dpi.
These findings pose several challenging questions. The first question
concerns whether the PrPSc recovered on first passage represents the residual
inoculum rather than de novo PrPSc generated by conversion of the host’s PrPC.
We believe this possibility is made unlikely by our experiment showing that the
PrPSc in the VPSPr inoculum was no longer detectable by immunohistochemical and
WB analyses in Tg(HuPrP-129VV) mice 35 dpi.
Furthermore, histopathologic changes and PrPSc detection, indicating VPSPr
transmission, were observed only when the host and the inoculum were syngenic at
PrP codon 129. This genotypic selectivity is not compatible with the notion that
the PrPSc detected in the hosts was from the residual inoculum. Finally, several
other studies have shown that PrPSc associated with the inoculum is rapidly
cleared (12,26–30). These observations support the conclusion that
histopathologic changes and the PrPSc recovered in the positive VPSPrchallenged
mice result from de novo mouse PrPSc generated by templated conversion, although
at a very low level. The lack of clinical signs in the affected mice can be
easily explained by the characteristics and localization of the plaques and of
the spongiform degeneration, both of which affected limited regions depopulated
of neuronal cells and processes.
Prion plaques similar in type and topography to those we observed have been
reported alone or associated with spongiform degeneration in mice challenged
with prions of various origins (9,11,29–32). In 3 studies, plaque deposits seem
to be especially similar to those observed by us. In the first, the plaques were
detected on the second passage of vCJD in Tg mice expressing human PrPC-129V
(Tg152) (11,29). The second and third studies used Tg mice expressing mouse PrP
harboring the P101L variation (101LL mice), which is the equivalent of the P102L
human mutation linked to a GSS subtype (9,30). In the last 2 experiments,
Tg101LL mice were challenged with “atypical” P102L GSS (i.e., GSS associated
only with 7-kDa PrPSc PK-resistant fragment rather than with the “typical” P102L
GSS that is also associated with the classical 3-band resPrPSc) or with BH from
TgGSS-22, a Tg mouse model of GSS in which prion disease spontaneously develops
(9,30). All affected mice of these 3 studies remained asymptomatic like those of
our study, further supporting the notion that focal prion plaque deposition in
periventricular regions is not sufficient to produce major clinical signs.
Despite the common histopathologic features, these mice were associated with
electrophoretically distinct PrPSc species.
In the experiment of vCJD transmission, PrPSc harvested from challenged
Tg152 mice showed the classical 3 PKresistant bands as in vCJD, but they
displayed a higher molecular mass than in vCJD (11). Minimal quantity of
resPrPSc recovered at ≈30 kDa was detected only in 1 of 5 plaque-harboring 101LL
mice challenged with atypical P102L GSS (9), whereas 101LL mice inoculated with
TgGSS-22 BH showed no detectable PrPSc by WB (30). Although to some extent the
variability of the PrPSc electrophoretic profiles between the experiments with
Tg101LL and our experiments might be due to variations in WB methods, the PrPSc
diversity in these 3 studies and in our study suggests that focal plaque
formation at the border between the hippocampus and corpus callosum is not
strictly PrPSc strain specific. However, this brief review indicates that
peri-hippocampal plaque deposition is preferentially detected in hosts
challenged with PrPSc species that form plaques in the natural disease, such as
vCJD, GSS, and VPSPr.
The lack of histologic lesions and PrPSc on second passage in both
Tg(HuPrP129V) and Tg(HuPrP129M) mice challenged with BH from the most severely
affected first-passage mice is unusual. However, comparable findings have been
reported in at least 2 previous studies. In the first, 101LL mice challenged
with affected TgGSS-22 BH (a Tg mouse in which a GSS-like disease spontaneously
develops) harbored fewer plaques on second passage than on first, suggesting
decreased replication of the seed on second passage (9,30). In the second study,
first passage of BH from cattle affected by bovine spongiform encephalopathy to
Tg152 mice (expressing human PrPC- 129V) resulted in clinical disease associated
with diffuse brain deposition of PrP as demonstrated by immunostaining (11),
even though no resPrPSc could be demonstrated by WB. On second passage in the
same Tg152 mice, no evidence of prion disease could be demonstrated either by
PrP immunostaining or WB, as in our study (11). However, BH from these negative
Tg152 produced a full prion disease after inoculation into wild-type FVB mice.
This remarkable finding indicates that prion transmissibility (or infectivity)
can be sustained in hosts with no demonstrable prion diseases (according to
commonly used methods), and that it can be rescued through passage to an
appropriate host (11).
Interpreting our findings also in the light of the above data, we propose
that normal human PrPC is not a suitable substrate (or mouse brain is not a
favorable environment) to sustain conversion to VPSPr PrPSc. Thus, long
incubations are required to induce modest and asymptomatic PrPSc deposition.
Nevertheless, the PrPSc generated in the host on first passage seems to match
the conformation of the PrPSc from the inoculum, based on the finding that
PK-resistant PrPSc fragments of similar size are recovered from host and donor
preparations. This also indicates that little or no PrPSc adaptation has
occurred during the first passage (32). The apparent failure of the second
passage to transmit detectable disease might be due to the inadequate
amplification of VPSPr PrPSc during primary transmission, which would result in
a second passage PrPSc inoculum more diluted than the VPSPr brain extract used
in the primary transmission. This line of reasoning raises the possibility that
if VPSPr PrPSc were exposed to a favorable PrP substrate (or brain environment),
it might replicate efficiently. This conjecture is reinforced by 2 recent
findings. First, preliminary findings show that VPSPr can be transmitted to bank
voles more easily than to the Tg(HuPrP) used in the present experiments (33).
Second, transmissibility of GSS linked to the A117V mutation has been recently
demonstrated (10). GSS-A117V is commonly viewed as a “classic” GSS subtype,
given the distinct features of its phenotype that is characterized by prominent
prion plaques with limited spongiform degeneration and a PrPSc WB profile
dominated by a highly PK-resistant fragment of 7–8 kDa (34). Early failures to
transmit GSS-A117V and the evidence that the presence of the A117V mutation
altered the topology of PrP led to the conclusions that 1) GSS-A117V was not
transmissible and 2) its underlying pathogenetic mechanism was not based on a
PrPC-to-PrPSc conversion process (8).
After inoculation with BH from GSS-A117V–affected patients, Tg mice
expressing human PrP, harboring the A117V mutation, developed a prion disease
associated with a histologic phenotype and PrPSc that roughly recapitulated
those of the human disease. However, only one fourth of the inoculated mice were
symptomatic with incubation periods >600 days, whereas more than half
harbored plaques, PrPSc, or both (10). No second passage was reported. This
study shows that an allegedly nontransmissible prion disease can be transmitted
(at least at first passage) if a suitable host is selected.
In conclusion, we propose that VPSPr is transmissible and, therefore, is an
authentic prion disease. However, transmissibility cannot be sustained through
serial passages presumably because human PrPC (or the mouse brain environment)
cannot efficiently convert and propagate the VPSPr PrPSc species. If this is the
case, uncovering the properties of human PrP that are required to replicate more
efficiently the prion strains associated with VPSPr may help clarify the PrPSc
mode of formation in this intriguing disease.
>>> We concluded that VPSPr is transmissible; thus, it is an
authentic prion disease.
Variably Protease-Sensitive Prionopathy, a Unique Prion Variant with
Inefficient Transmission
Properties Abigail B. Diack,1 Diane L. Ritchie,1 Alexander H. Peden,
Deborah Brown, Aileen Boyle, Laura Morabito, David Maclennan, Paul Burgoyne,
Casper Jansen, Richard S. Knight, Pedro Piccardo, James W. Ironside,1 and Jean
C. Manson1
Variably protease-sensitive prionopathy (VPSPr) can occur in persons of all
codon 129 genotypes in the human prion protein gene (PRNP) and is characterized
by a unique biochemical profile when compared with other human prion diseases.
We investigated transmission properties of VPSPr by inoculating transgenic mice
expressing human PRNP with brain tissue from 2 persons with the
valine-homozygous (VV) and 1 with the heterozygous methionine/valine codon 129
genotype. No clinical signs or vacuolar pathology were observed in any
inoculated mice. Small deposits of prion protein accumulated in the brains of
inoculated mice after challenge with brain material from VV VPSPr patients. Some
of these deposits resembled microplaques that occur in the brains of VPSPr
patients. Comparison of these transmission properties with those of sporadic
Creutzfeldt-Jakob disease in the same lines of mice indicated that VPSPr has
distinct biological properties. Moreover, we established that VPSPr has limited
potential for human-to-human transmission.
snip...
Discussion
The inoculation of homogenates prepared from the brains of 3 patients with
VPSPr (UK-MV, UK-VV and NL-VV) into transgenic mice expressing the different
forms of the human PrP gene has resulted in very
different transmission properties when compared with those of previously
characterized sCJD strains (3). No clinical disease or vacuolar pathology was
observed in any of the mice. The only evidence for transmission of disease was
the neuropathologic finding of abnormal PrP accumulation in the form of
microplaque-like and granular deposits in the hippocampus and subventricular
areas of the brain. These results contrast considerably with those observed with
sCJD in the same HuMM/HuMV/ HuVV mouse lines (3). Sporadic CJD transmits to all
these mouse lines, as indicated by evidence of clinical signs and vacuolar
pathology and/or PrP deposition, and the combination of these transmission
properties has resulted in the identification of 4 strains of sCJD (3). Of the 4
sCJD strains, subtype VV2 showed the greatest frequency of clinical (13/16),
vacuolar (16/16), and pathologic (15/15) signs of prion disease following
inoculation into HuVV mice (Table 3) (3). In contrast, the MM2 subtype of sCJD
showed the least transmission to the mice: no mice had clinical signs or
vacuolar pathology, and only 3 of 17 HuVV and 2 of 18 HuMV mice had evidence of
PrP deposition in the form of small punctate deposits in the thalamus (Table 3)
(3). Although this transmission of the MM2 subtype might be considered similar
to that of VPSPr, the PrP deposition differed in form and brain area compared
with the deposition observed in the VPSPr studies. Unlike sCJD, which shows
transmission from patients with all 3 codon 129 genotypes, only VPSPr from the 2
patients with codon 129VV provided evidence of transmission.
This low rate of transmission may be due to low levels of PrPres in the
brain homogenates that were inoculated, or it could be that the PrP genotype
plays a role in transmission of disease.
Prion disease propagation involves the aggregation of abnormal PrP that
acts as a template for further aggregation within the brain, a process termed
seeding (21,22). The spread of PrP within the brain appears to occur in
cell-to-cell fashion in well-defined neuroanatomic pathways (23), the mechanisms
of which are yet to be elucidated despite extensive studies. Prion diseases have
the potential to be transmissible between persons, a fact that raises public
health concerns, particularly regarding vCJD. Assessing the risk for
transmission is a challenge because of the varied nature of prion diseases and
conflicting evidence over the mechanisms of transmission. Risk assessment is
made even more complicated by the existence of prion disease models in which
negligible amounts of PrPres are associated with high infectivity titers in vivo
(24) and also of models in which PrPres in the form of amyloid plaques develops
in the absence of clinical disease or spongiform changes (25).
It could be argued that the observation of small plaque-like amyloid
deposits in the brains of mice with no neurologic signs of disease after the
inoculation of brain homogenates prepared from patients with VPSPr does not
indicate disease transmission. Instead, the deposits could indicate an amyloid
seeding phenomenon akin to that observed following the experimental inoculation
of primates with brain tissue from patients with Alzheimer disease (26). In
those experiments, amyloid β seeding occurred in the primate brain in the
absence of any clinical signs. Precedence of this phenomenon in prion disease
has been set by Piccardo et al. (27), who showed similar results in a mouse
model system of prion disease transmission. However, in our study, the brain of
1 mouse exhibited intensely stained, small, round granules within the
hippocampus in addition to the plaque-like deposits (Figure 4). These small
granules are reminiscent of the microplaques found in brain tissue of humans
with VPSPr (4,5). Furthermore, with 4 PrP antibodies, the microplaque deposits
in the mouse brain showed the same pattern of differential immunoreactivity as
that in the brain of patients with VPSPr (5,6,17). Moreover astrocytosis in the
vicinity of the microplaques was also observed in this mouse (Figure 5). This
type of astrocytic response is observed in all our model systems of
transmissible prion disease, but is absent from the nontransmissible forms of
PrP (i.e., amyloid plaques in absence of clinical disease), suggesting that this
single mouse may represent a transmission of infection rather than a consequence
of seeding of inoculum (25,28). Second passage in the same mouse line will be
required to prove this interpretation, but such a study will take an additional
3 years to complete. Although understanding the mechanisms of transmission is an
interesting facet of this study, our primary finding is that VPSPr is capable of
transmission to transgenic mice expressing PrP, albeit at extremely low levels
compared with those of other transmissible prion diseases (e.g., sCJD and vCJD).
We demonstrate that VPSPr is a disease with biological properties distinct from
those of sCJD and with a limited, but not negligible, potential for infectivity.
These results demonstrate the importance of continuing surveillance to fully
uncover the growing spectrum of human prion diseases.
>>> We demonstrate that VPSPr is a disease with biological
properties distinct from those of sCJD and with a limited, but not negligible,
potential for infectivity. These results demonstrate the importance of
continuing surveillance to fully uncover the growing spectrum of human prion
diseases.
Friday, January 10, 2014
vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type
prion disease, what it ???
Monday, November 3, 2014
*** The prion protein protease sensitivity, stability and seeding activity
in variably protease sensitive prionopathy brain tissue suggests molecular
overlaps with sporadic Creutzfeldt-Jakob disease
*** 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.
VARIABLY PROTEASE-SENSITVE PRIONOPATHY IS TRANSMISSIBLE ...price of prion
poker goes up again $
OR-10: Variably protease-sensitive prionopathy is transmissible in bank
voles
Romolo Nonno,1 Michele Di Bari,1 Laura Pirisinu,1 Claudia D’Agostino,1
Stefano Marcon,1 Geraldina Riccardi,1 Gabriele Vaccari,1 Piero Parchi,2 Wenquan
Zou,3 Pierluigi Gambetti,3 Umberto Agrimi1 1Istituto Superiore di Sanità; Rome,
Italy; 2Dipartimento di Scienze Neurologiche, Università di Bologna; Bologna,
Italy; 3Case Western Reserve University; Cleveland, OH USA
Background. Variably protease-sensitive prionopathy (VPSPr) is a recently
described “sporadic”neurodegenerative disease involving prion protein
aggregation, which has clinical similarities with non-Alzheimer dementias, such
as fronto-temporal dementia. Currently, 30 cases of VPSPr have been reported in
Europe and USA, of which 19 cases were homozygous for valine at codon 129 of the
prion protein (VV), 8 were MV and 3 were MM. A distinctive feature of VPSPr is
the electrophoretic pattern of PrPSc after digestion with proteinase K (PK).
After PK-treatment, PrP from VPSPr forms a ladder-like electrophoretic pattern
similar to that described in GSS cases. The clinical and pathological features
of VPSPr raised the question of the correct classification of VPSPr among prion
diseases or other forms of neurodegenerative disorders. Here we report
preliminary data on the transmissibility and pathological features of VPSPr
cases in bank voles.
Materials and Methods. Seven VPSPr cases were inoculated in two genetic
lines of bank voles, carrying either methionine or isoleucine at codon 109 of
the prion protein (named BvM109 and BvI109, respectively). Among the VPSPr cases
selected, 2 were VV at PrP codon 129, 3 were MV and 2 were MM. Clinical
diagnosis in voles was confirmed by brain pathological assessment and western
blot for PK-resistant PrPSc (PrPres) with mAbs SAF32, SAF84, 12B2 and 9A2.
Results. To date, 2 VPSPr cases (1 MV and 1 MM) gave positive transmission
in BvM109. Overall, 3 voles were positive with survival time between 290 and 588
d post inoculation (d.p.i.). All positive voles accumulated PrPres in the form
of the typical PrP27–30, which was indistinguishable to that previously observed
in BvM109 inoculated with sCJDMM1 cases.
In BvI109, 3 VPSPr cases (2 VV and 1 MM) showed positive transmission until
now. Overall, 5 voles were positive with survival time between 281 and 596
d.p.i.. In contrast to what observed in BvM109, all BvI109 showed a GSS-like
PrPSc electrophoretic pattern, characterized by low molecular weight PrPres.
These PrPres fragments were positive with mAb 9A2 and 12B2, while being negative
with SAF32 and SAF84, suggesting that they are cleaved at both the C-terminus
and the N-terminus. Second passages are in progress from these first successful
transmissions.
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.
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.
Monday, August 9, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the
prion protein or just more Prionbaloney ?
Wednesday, March 28, 2012
VARIABLY PROTEASE-SENSITVE PRIONOPATHY IS TRANSMISSIBLE ...price of prion
poker goes up again $
OR-10 15:25 - 15:40 VARIABLY PROTEASE-SENSITIVE PRIONOPATHY IS
TRANSMISSIBLE IN BANK VOLES Nonno
Monday, February 24, 2014
Sporadic Fatal Insomnia in an Adolescent
To the best of our knowledge, this is the first case of CJD combined with
Lewy body disease and argirophilic grain disease. Furthermore, we believe this
case is an extremely rare combination of MM2-cortical-type and MM2-thalamic-type
sporadic CJD (sCJD), which explains the broad spectrum of MM2-type sCJD findings
and symptoms. Moreover, histological features of possible Alzheimer's disease
were also reported.
Wednesday, September 03, 2014
Coexistence of mixed phenotype Creutzfeldt-Jakob disease, Lewy body disease
and argyrophilic grain disease plus histological features of possible
Alzheimer's disease: A multi-protein disorder in an autopsy case
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
Monday, October 10, 2011
EFSA Journal 2011 The European Response to BSE: A Success Story
snip...
EFSA and the European Centre for Disease Prevention and Control (ECDC)
recently delivered a scientific opinion on any possible epidemiological or
molecular association between TSEs in animals and humans (EFSA Panel on
Biological Hazards (BIOHAZ) and ECDC, 2011). This opinion confirmed Classical
BSE prions as the only TSE agents demonstrated to be zoonotic so far but the
possibility that a small proportion of human cases so far classified as
"sporadic" CJD are of zoonotic origin could not be excluded. Moreover,
transmission experiments to non-human primates suggest that some TSE agents in
addition to Classical BSE prions in cattle (namely L-type Atypical BSE,
Classical BSE in sheep, transmissible mink encephalopathy (TME) and chronic
wasting disease (CWD) agents) might have zoonotic potential.
snip...
see follow-up here about North America BSE Mad Cow TSE prion risk factors,
and the ever emerging strains of Transmissible Spongiform Encephalopathy in many
species here in the USA, including humans ;
Thursday, August 12, 2010
Seven main threats for the future linked to prions
First threat
The TSE road map defining the evolution of European policy for protection
against prion diseases is based on a certain numbers of hypotheses some of which
may turn out to be erroneous. In particular, a form of BSE (called atypical
Bovine Spongiform Encephalopathy), recently identified by systematic testing in
aged cattle without clinical signs, may be the origin of classical BSE and thus
potentially constitute a reservoir, which may be impossible to eradicate if a
sporadic origin is confirmed.
***Also, a link is suspected between atypical BSE and some apparently
sporadic cases of Creutzfeldt-Jakob disease in humans. These atypical BSE cases
constitute an unforeseen first threat that could sharply modify the European
approach to prion diseases.
Second threat
snip...
Saturday, June 25, 2011
Transmissibility of BSE-L and Cattle-Adapted TME Prion Strain to Cynomolgus
Macaque
"BSE-L in North America may have existed for decades"
Over the next 8-10 weeks, approximately 40% of all the adult mink on the
farm died from TME.
snip...
The rancher was a ''dead stock'' feeder using mostly (>95%) downer or
dead dairy cattle...
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
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
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.
Saturday, July 6, 2013
Small Ruminant Nor98 Prions Share Biochemical Features with Human
Gerstmann-Sträussler-Scheinker Disease and Variably Protease-Sensitive
Prionopathy
Research Article
Transmissible Spongiform Encephalopathy TSE Prion Disease North America
2014
Transmissible Spongiform Encephalopathy TSE Prion Disease have now been
discovered in a wide verity of species across North America. typical C-BSE,
atypical L-type BASE BSE, atypical H-type BSE, atypical H-G BSE, of the bovine,
typical and atypical Scrapie strains, in sheep and goats, with atypical Nor-98
Scrapie spreading coast to coast in about 5 years. Chronic Wasting Disease CWD
in cervid is slowly spreading without any stopping it in Canada and the USA and
now has mutated into many different strains. Transmissible Mink Encephalopathy
TME outbreaks. These Transmissible Spongiform Encephalopathy TSE Prion Disease
have been silently mutating and spreading in different species in North America
for decades.
The USDA, FDA, et al have assured us of a robust Triple BSE TSE prion
Firewall, of which we now know without a doubt, that it was nothing but ink on
paper. Since the 1997 mad cow feed ban in the USA, literally tons and tons of
banned mad cow feed has been put out into commerce, never to return, as late as
December of 2013, serious, serious breaches in the FDA mad cow feed ban have
been documented. The 2004 enhanced BSE surveillance program was so flawed, that
one of the top TSE prion Scientist for the CDC, Dr. Paul Brown stated ; Brown,
who is preparing a scientific paper based on the latest two mad cow cases to
estimate the maximum number of infected cows that occurred in the United States,
said he has "absolutely no confidence in USDA tests before one year ago" because
of the agency's reluctance to retest the Texas cow that initially tested
positive.
see ;
The BSE surveillance and testing have also been proven to be flawed, and
the GAO and OIG have both raised serious question as to just how flawed it has
been (see GAO and OIG reports). North America has more documented TSE prion
disease, in different documented species (excluding the Zoo BSE animals in the
EU), then any other place on the Globe. This does not include the very
likelihood that TSE prion disease in the domestic feline and canine have been
exposed to high doses of the TSE prion disease vid pet food. To date, it’s still
legal to include deer from cwd zone into pet food or deer food. Specified Risk
Material i.e. SRM bans still being breach, as recently as just last month.
nvCJD or what they now call vCJD, another case documented in Texas last
month, with very little information being released to the public on about this
case? with still the same line of thought from federal officials, ‘it can’t
happen here’, so another vCJD blamed on travel of a foreign animal disease from
another country, while ignoring all the BSE TSE Prion risk factors we have here
in the USA and Canada, and the time that this victim and others, do spend in the
USA, and exposed to these risk factors, apparently do not count in any way with
regard to risk factor. a flawed process of risk assessment.
sporadic CJD, along with new TSE prion disease in humans, of which the
young are dying, of which long duration of illness from onset of symptoms to
death have been documented, only to have a new name added to the pot of prion
disease i.e. sporadic GSS, sporadic FFI, and or VPSPR. I only ponder how a
familial type disease could be sporadic with no genetic link to any family
member? when the USA is the only documented Country in the world to have
documented two different cases of atypical H-type BSE, with one case being
called atypical H-G BSE with the G meaning Genetic, with new science now showing
that indeed atypical H-type BSE is very possible transmitted to cattle via oral
transmission (Prion2014). sporadic CJD and VPSPR have been rising in Canada,
USA, and the UK, with the same old excuse, better surveillance. You can only use
that excuse for so many years, for so many decades, until one must conclude that
CJD TSE prion cases are rising. a 48% incease in CJD in Canada is not just a
blip or a reason of better surveillance, it is a mathematical rise in numbers.
More and more we are seeing more humans exposed in various circumstance in the
Hospital, Medical, Surgical arenas to the TSE Prion disease, and at the same
time in North America, more and more humans are becoming exposed to the TSE
prion disease via consumption of the TSE prion via deer and elk, cattle, sheep
and goats, and for those that are exposed via or consumption, go on to further
expose many others via the iatrogenic modes of transmission of the TSE prion
disease i.e. friendly fire. I pondered this mode of transmission via the victims
of sporadic FFI, sporadic GSS, could this be a iatrogenic event from someone
sub-clinical with sFFI or sGSS ? what if?
Two decades have passed since Dr. Ironside first confirmed his first ten
nvCJD victims in 1995. Ten years later, 2005, we had Dr. Gambetti and his first
ten i.e. VPSPR in younger victims. now we know that indeed VPSPR is
transmissible. yet all these TSE prion disease and victims in the USA and Canada
are being pawned off as a spontaneous event, yet science has shown, the
spontaneous theory has never been proven in any natural case of TSE prion
disease, and scientist have warned, that they have now linked some sporadic CJD
cases to atypical BSE, to atypical Scrapie, and to CWD, yet we don’t here about
this in the public domain. We must make all human and animal TSE prion disease
reportable in every age group, in ever state and internationally, we must have a
serious re-evaluation and testing of the USA cattle herds, and we must ban
interstate movement of all cervids. Any voluntary effort to do any of this will
fail. Folks, we have let the industry run science far too long with regards to
the TSE prion disease. While the industry and their lobbyist continues to funnel
junk science to our decision policy makers, Rome burns. ...end
REFERENCES
Sunday, June 29, 2014
Transmissible Spongiform Encephalopathy TSE Prion Disease North America
2014
Tuesday, August 12, 2014
MAD COW USDA TSE PRION COVER UP or JUST IGNORANCE, for the record AUGUST
2014
Sunday, July 06, 2014
Dietary Risk Factors for Sporadic Creutzfeldt-Jakob Disease: A Confirmatory
Case-Control Study
Conclusions—The a priori hypotheses were supported.
*Consumption of various meat products may be one method of transmission of
the infectious agent for sCJD.
Monday, November 3, 2014
USA CJD TSE PRION UNIT, TEXAS, SURVEILLANCE UPDATE NOVEMBER 2014
National Prion Disease Pathology Surveillance Center Cases Examined1
(October 7, 2014)
***6 Includes 11 cases in which the diagnosis is pending, and 19
inconclusive cases;
***7 Includes 12 (11 from 2014) cases with type determination pending in
which the diagnosis of vCJD has been excluded.
***The sporadic cases include 2660 cases of sporadic Creutzfeldt-Jakob
disease (sCJD),
***50 cases of Variably Protease-Sensitive Prionopathy (VPSPr)
***and 21 cases of sporadic Fatal Insomnia (sFI).
Sunday, November 23, 2014
*** Confirmed Variant Creutzfeldt-Jakob Disease (variant CJD) Case in Texas
in June 2014 confirmed as USA case NOT European
Terry S. Singeltary Sr. on the Creutzfeldt-Jakob Disease Public Health
Crisis *video*
Jeff Schwan, sporadic cjd, clustering, and BSE aka mad cow type disease, is
there a link ? *video*
1997-11-10: Panorama - The british disease *video*
Sunday, September 6, 2009
MAD COW USA 1997 *video*
Tuesday, November 04, 2014
The pathological and molecular but not clinical phenotypes are maintained
after second passage of experimental atypical bovine spongiform encephalopathy
in cattle
*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics
of BSE in Canada Singeltary reply ;
Tuesday, August 12, 2014
MAD COW USDA TSE PRION COVER UP or JUST IGNORANCE, for the record AUGUST
2014
Thursday, October 02, 2014
[Docket No. APHIS-2013-0064] Concurrence With OIE Risk Designations for
Bovine Spongiform Encephalopathy
Saturday, August 14, 2010
BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and
VPSPr PRIONPATHY
2009 UPDATE ON ALABAMA AND TEXAS MAD COWS 2005 and 2006
Self-Propagative Replication of Ab Oligomers Suggests Potential
Transmissibility in Alzheimer Disease
Received July 24, 2014; Accepted September 16, 2014; Published November 3,
2014
Singeltary comment ;
TSS
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.