Sunday, August 01, 2010
Blood product, collected from a
donors possibly at increased risk for vCJD only, was distributed USA JULY 2010
http://vcjdtransfusion.blogspot.com/2010/08/blood-product-collected-from-donors.html
Tuesday, September 14, 2010
Transmissible Spongiform
Encephalopathies Advisory Committee; Notice of Meeting October 28 and 29, 2010
(COMMENT SUBMISSION)
http://tseac.blogspot.com/2010/09/transmissible-spongiform_14.html
nothing like missing the bigger picture, but they been missing
(ignroing) it since 1985 $$$
*** 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.
http://www.landesbioscience.com/journals/prion/01-Prion6-2-OralPresentations.pdf?nocache=1216084967
Wednesday, March 28, 2012
VARIABLY PROTEASE-SENSITVE
PRIONOPATHY IS TRANSMISSIBLE, price of prion poker goes up again $
http://prionopathy.blogspot.com/2012/03/variably-protease-sensitve-prionopathy.html
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...
http://www.neuroprion.org/en/np-neuroprion.html
Thursday, August 12, 2010
Seven main threats for the future linked to
prions
http://prionpathy.blogspot.com/2010/08/seven-main-threats-for-future-linked-to.html
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...
http://www.efsa.europa.eu/en/efsajournal/pub/e991.htm?emt=1
http://www.efsa.europa.eu/en/efsajournal/doc/e991.pdf
Rural and Regional Affairs and Transport References Committee
The possible impacts and consequences for public health, trade and
agriculture of the Government's decision to relax import restrictions on beef
Final report June 2010
2.65 At its hearing on 14 May 2010, the committee
heard evidence from Dr Alan Fahey who has recently submitted a thesis on the
clinical neuropsychiatric, epidemiological and diagnostic features of
Creutzfeldt-Jakob disease.48 Dr Fahey told the committee of his concerns
regarding the lengthy incubation period for transmissible spongiform
encephalopathies, the inadequacy of current tests and the limited nature of our
current understanding of this group of diseases.49
2.66 Dr Fahey also
told the committee that in the last two years a link has been established
between forms of atypical CJD and atypical BSE. Dr Fahey said that: They now
believe that those atypical BSEs overseas are in fact causing sporadic
Creutzfeldt-Jakob disease. They were not sure if it was due to mad sheep disease
or a different form. If you look in the textbooks it looks like this is just
arising by itself. But in my research I have a summary of a document which
states that there has never been any proof that sporadic Creutzfeldt-Jakob
disease has arisen de novo-has arisen of itself. There is no proof of that. The
recent research is that in fact it is due to atypical forms of mad cow disease
which have been found across Europe, have been found in America and have been
found in Asia. These atypical forms of mad cow disease typically have even
longer incubation periods than the classical mad cow disease.50
http://www.aph.gov.au/senate/committee/rrat_ctte/mad_cows/report/report.pdf
Atypical BSE in Cattle
To date the OIE/WAHO assumes that the
human and animal health standards set out in the BSE chapter for classical BSE
(C-Type) applies to all forms of BSE which include the H-type and L-type
atypical forms. This assumption is scientifically not completely justified and
accumulating evidence suggests that this may in fact not be the case. Molecular
characterization and the spatial distribution pattern of histopathologic lesions
and immunohistochemistry (IHC) signals are used to identify and characterize
atypical BSE. Both the L-type and H-type atypical cases display significant
differences in the conformation and spatial accumulation of the disease
associated prion protein (PrPSc) in brains of afflicted cattle. Transmission
studies in bovine transgenic and wild type mouse models support that the
atypical BSE types might be unique strains because they have different
incubation times and lesion profiles when compared to C-type BSE. When L-type
BSE was inoculated into ovine transgenic mice and Syrian hamster the resulting
molecular fingerprint had changed, either in the first or a subsequent passage,
from L-type into C-type BSE.
In addition, non-human primates are
specifically susceptible for atypical BSE as demonstrated by an approximately
50% shortened incubation time for L-type BSE as compared to C-type. Considering
the current scientific information available, it cannot be assumed that these
different BSE types pose the same human health risks as C-type BSE or that these
risks are mitigated by the same protective measures.
This study will
contribute to a correct definition of specified risk material (SRM) in atypical
BSE. The incumbent of this position will develop new and transfer existing,
ultra-sensitive methods for the detection of atypical BSE in tissue of
experimentally infected cattle.
http://www.prionetcanada.ca/detail.aspx?menu=5&dt=293380&app=93&cat1=387&tp=20&lk=no&cat2
P.4.23
Transmission of atypical BSE in humanized mouse models
Liuting Qing1, Wenquan Zou1, Cristina Casalone2, Martin Groschup3,
Miroslaw Polak4, Maria Caramelli2, Pierluigi Gambetti1, Juergen Richt5,
Qingzhong Kong1 1Case Western Reserve University, USA; 2Instituto
Zooprofilattico Sperimentale, Italy; 3Friedrich-Loeffler-Institut, Germany;
4National Veterinary Research Institute, Poland; 5Kansas State University
(Previously at USDA National Animal Disease Center), USA
Background:
Classical BSE is a world-wide prion disease in cattle, and the classical BSE
strain (BSE-C) has led to over 200 cases of clinical human infection (variant
CJD). Atypical BSE cases have been discovered in three continents since 2004;
they include the L-type (also named BASE), the H-type, and the first reported
case of naturally occurring BSE with mutated bovine PRNP (termed BSE-M). The
public health risks posed by atypical BSE were largely undefined.
Objectives: To investigate these atypical BSE types in terms of their
transmissibility and phenotypes in humanized mice. Methods: Transgenic mice
expressing human PrP were inoculated with several classical (C-type) and
atypical (L-, H-, or Mtype) BSE isolates, and the transmission rate, incubation
time, characteristics and distribution of PrPSc, symptoms, and histopathology
were or will be examined and compared.
Results: Sixty percent of
BASE-inoculated humanized mice became infected with minimal spongiosis and an
average incubation time of 20-22 months, whereas only one of the C-type
BSE-inoculated mice developed prion disease after more than 2 years.
Protease-resistant PrPSc in BASE-infected humanized Tg mouse brains was
biochemically different from bovine BASE or sCJD. PrPSc was also detected in the
spleen of 22% of BASE-infected humanized mice, but not in those infected with
sCJD. Secondary transmission of BASE in the humanized mice led to a small
reduction in incubation time.*** The atypical BSE-H strain is also transmissible
with distinct phenotypes in the humanized mice, but no BSE-M transmission has
been observed so far.
Discussion: Our results demonstrate that BASE is
more virulent than classical BSE, has a lymphotropic phenotype, and displays a
modest transmission barrier in our humanized mice. BSE-H is also transmissible
in our humanized Tg mice. The possibility of more than two atypical BSE strains
will be discussed.
Supported by NINDS NS052319, NIA AG14359, and NIH AI
77774.
http://www.prion2009.com/sites/default/files/Prion2009_Book_of_Abstracts.pdf
P26 TRANSMISSION OF ATYPICAL BOVINE SPONGIFORM ENCEPHALOPATHY (BSE)
IN HUMANIZED MOUSE MODELS
Liuting Qing1, Fusong Chen1, Michael Payne1,
Wenquan Zou1, Cristina Casalone2, Martin Groschup3, Miroslaw Polak4, Maria
Caramelli2, Pierluigi Gambetti1, Juergen Richt5*, and Qingzhong Kong1
1Department of Pathology, Case Western Reserve University, Cleveland, OH 44106,
USA; 2CEA, Istituto Zooprofilattico Sperimentale, Italy;
3Friedrich-Loeffler-Institut, Germany; 4National Veterinary Research Institute,
Poland; 5Kansas State University, Diagnostic Medicine/Pathobiology Department,
Manhattan, KS 66506, USA. *Previous address: USDA National Animal Disease
Center, Ames, IA 50010, USA
Classical BSE is a world-wide prion disease
in cattle, and the classical BSE strain (BSE-C) has led to over 200 cases of
clinical human infection (variant CJD). Two atypical BSE strains, BSE-L (also
named BASE) and BSE-H, have been discovered in three continents since 2004. The
first case of naturally occurring BSE with mutated bovine PrP gene (termed
BSE-M) was also found in 2006 in the USA. The transmissibility and phenotypes of
these atypical BSE strains/isolates in humans were unknown. We have inoculated
humanized transgenic mice with classical and atypical BSE strains (BSE-C, BSE-L,
BSE-H) and the BSE-M isolate. We have found that the atypical BSE-L strain is
much more virulent than the classical BSE-C. *** The atypical BSE-H strain is
also transmissible in the humanized transgenic mice with distinct phenotype, but
no transmission has been observed for the BSE-M isolate so far.
III
International Symposium on THE NEW PRION BIOLOGY: BASIC SCIENCE, DIAGNOSIS AND
THERAPY 2 - 4 APRIL 2009, VENEZIA (ITALY)
http://www.istitutoveneto.it/prion_09/Abstracts_09.pdf
I ask Professor Kong ;
Thursday, December 04, 2008 3:37 PM
Subject: RE: re--Chronic Wating Disease (CWD) and Bovine Spongiform
Encephalopathies (BSE): Public Health Risk Assessment
''IS the h-BSE
more virulent than typical BSE as well, or the same as cBSE, or less virulent
than cBSE? just curious.....''
Professor Kong reply ;
.....snip
''As to the H-BSE, we do not have sufficient data to say one way or
another, but we have found that H-BSE can infect humans. I hope we could publish
these data once the study is complete. Thanks for your interest.''
Best
regards, Qingzhong Kong, PhD Associate Professor Department of Pathology Case
Western Reserve University Cleveland, OH 44106 USA
END...TSS
Thursday, December 04, 2008 2:37 PM
"we have found that H-BSE
can infect humans."
personal communication with Professor Kong. ...TSS
BSE-H is also transmissible in our humanized Tg mice.
The
possibility of more than two atypical BSE strains will be discussed.
Supported by NINDS NS052319, NIA AG14359, and NIH AI 77774.
http://www.prion2009.com/sites/default/files/Prion2009_Book_of_Abstracts.pdf
http://transmissiblespongiformencephalopathy.blogspot.com/2011/06/experimental-h-type-bovine-spongiform.html
http://bse-atypical.blogspot.com/2012/03/experimental-h-type-and-l-type-bovine.html
Atypical BSE (BASE) Transmitted from Asymptomatic Aging Cattle to a
Primate
Emmanuel E. Comoy1*, Cristina Casalone2, Nathalie
Lescoutra-Etchegaray1, Gianluigi Zanusso3, Sophie Freire1, Dominique Marcé1,
Frédéric Auvré1, Marie-Magdeleine Ruchoux1, Sergio Ferrari3, Salvatore Monaco3,
Nicole Salès4, Maria Caramelli2, Philippe Leboulch1,5, Paul Brown1, Corinne I.
Lasmézas4, Jean-Philippe Deslys1
1 Institute of Emerging Diseases and
Innovative Therapies, CEA, Fontenay-aux-Roses, France, 2 Istituto
Zooprofilattico Sperimentale del Piemonte, Turin, Italy, 3 Policlinico G.B.
Rossi, Verona, Italy, 4 Scripps Florida, Jupiter, Florida, United States of
America, 5 Genetics Division, Brigham & Women's Hospital, Harvard Medical
School, Boston, Massachusetts, United States of America
Abstract Top
Background Human variant Creutzfeldt-Jakob Disease (vCJD) results from foodborne
transmission of prions from slaughtered cattle with classical Bovine Spongiform
Encephalopathy (cBSE). Atypical forms of BSE, which remain mostly asymptomatic
in aging cattle, were recently identified at slaughterhouses throughout Europe
and North America, raising a question about human susceptibility to these new
prion strains.
Methodology/Principal Findings Brain homogenates from
cattle with classical BSE and atypical (BASE) infections were inoculated
intracerebrally into cynomolgus monkeys (Macacca fascicularis), a non-human
primate model previously demonstrated to be susceptible to the original strain
of cBSE. The resulting diseases were compared in terms of clinical signs,
histology and biochemistry of the abnormal prion protein (PrPres). The single
monkey infected with BASE had a shorter survival, and a different clinical
evolution, histopathology, and prion protein (PrPres) pattern than was observed
for either classical BSE or vCJD-inoculated animals. Also, the biochemical
signature of PrPres in the BASE-inoculated animal was found to have a higher
proteinase K sensitivity of the octa-repeat region. We found the same
biochemical signature in three of four human patients with sporadic CJD and an
MM type 2 PrP genotype who lived in the same country as the infected bovine.
Conclusion/Significance Our results point to a possibly higher degree of
pathogenicity of BASE than classical BSE in primates and also raise a question
about a possible link to one uncommon subset of cases of apparently sporadic
CJD. Thus, despite the waning epidemic of classical BSE, the occurrence of
atypical strains should temper the urge to relax measures currently in place to
protect public health from accidental contamination by BSE-contaminated
products.
Citation: Comoy EE, Casalone C, Lescoutra-Etchegaray N,
Zanusso G, Freire S, et al. (2008) Atypical BSE (BASE) Transmitted from
Asymptomatic Aging Cattle to a Primate. PLoS ONE 3(8): e3017.
doi:10.1371/journal.pone.0003017
Editor: Neil Mabbott, University of
Edinburgh, United Kingdom
Received: April 24, 2008; Accepted: August 1,
2008; Published: August 20, 2008
Copyright: © 2008 Comoy et al. This is
an open-access article distributed under the terms of the Creative Commons
Attribution License, which permits unrestricted use, distribution, and
reproduction in any medium, provided the original author and source are
credited.
Funding: This work has been supported by the Network of
Excellence NeuroPrion.
Competing interests: CEA owns a patent covering
the BSE diagnostic tests commercialized by the company Bio-Rad.
*
E-mail:
mailto:emmanuel.comoy%40cea.fr
snip...
In summary, we have transmitted one atypical form of BSE
(BASE) to a cynomolgus macaque monkey that had a shorter incubation period than
monkeys infected with classical BSE, with distinctive clinical,
neuropathological, and biochemical features; and have shown that the molecular
biological signature resembled that seen in a comparatively uncommon subtype of
sporadic CJD. We cannot yet say whether BASE is more pathogenic for primates
(including humans) than cBSE, nor can we predict whether its molecular
biological features represent a clue to one cause of apparently sporadic human
CJD. However, the evidence presented here and by others justifies concern about
a potential human health hazard from undetected atypical forms of BSE, and
despite the waning epizoonosis of classical BSE, it would be premature to
abandon the precautionary measures that have been so successful in reversing the
impact of cBSE. We would instead urge a gradual, staged reduction that takes
into account the evolving knowledge about atypical ruminant diseases, and both a
permanent ban on the use of bovine central nervous system tissue for either
animal or human use, and its destruction so as to eliminate any risk of
environmental contamination.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0003017
Proc Natl Acad Sci U S A. 2004 March 2; 101(9): 3065–3070. Published
online 2004 February 17. doi: 10.1073/pnas.0305777101 PMCID: PMC365745 Medical
Sciences
Identification of a second bovine amyloidotic spongiform
encephalopathy: Molecular similarities with sporadic Creutzfeldt-Jakob disease
Cristina Casalone,*† Gianluigi Zanusso,†‡ Pierluigi Acutis,* Sergio
Ferrari,‡ Lorenzo Capucci,§ Fabrizio Tagliavini,¶ Salvatore Monaco,‡ and Maria
Caramelli*
Abstract
Transmissible spongiform encephalopathies
(TSEs), or prion diseases, are mammalian neurodegenerative disorders
characterized by a posttranslational conversion and brain accumulation of an
insoluble, protease-resistant isoform (PrPSc) of the host-encoded cellular prion
protein (PrPC). Human and animal TSE agents exist as different phenotypes that
can be biochemically differentiated on the basis of the molecular mass of the
protease-resistant PrPSc fragments and the degree of glycosylation.
Epidemiological, molecular, and transmission studies strongly suggest that the
single strain of agent responsible for bovine spongiform encephalopathy (BSE)
has infected humans, causing variant Creutzfeldt-Jakob disease. The
unprecedented biological properties of the BSE agent, which circumvents the
so-called ”species barrier” between cattle and humans and adapts to different
mammalian species, has raised considerable concern for human health. To date, it
is unknown whether more than one strain might be responsible for cattle TSE or
whether the BSE agent undergoes phenotypic variation after natural transmission.
Here we provide evidence of a second cattle TSE. The disorder was pathologically
characterized by the presence of PrP-immunopositive amyloid plaques, as opposed
to the lack of amyloid deposition in typical BSE cases, and by a different
pattern of regional distribution and topology of brain PrPSc accumulation. In
addition, Western blot analysis showed a PrPSc type with predominance of the low
molecular mass glycoform and a protease-resistant fragment of lower molecular
mass than BSE-PrPSc. Strikingly, the molecular signature of this previously
undescribed bovine PrPSc was similar to that encountered in a distinct subtype
of sporadic Creutzfeldt-Jakob disease.
snip...
Phenotypic
Similarities Between BASE and sCJD. The transmissibility of CJD brains was
initially demonstrated in primates (27), and classification of atypical cases as
CJD was based on this property (28). To date, no systematic studies of strain
typing in sCJD have been provided, and classification of different subtypes is
based on clinical, neuropathological, and molecular features (the polymorphic
PRNP codon 129 and the PrPSc glycotype) (8, 9, 15, 19). The importance of
molecular PrPSc characterization in assessing the identity of TSE strains is
underscored by several studies, showing that the stability of given
disease-specific PrPSc types is maintained upon experimental propagation of
sCJD, familial CJD, and vCJD isolates in transgenic PrP-humanized mice (8, 29).
Similarly, biochemical properties of BSE- and vCJD-associated PrPSc molecules
remain stable after passage to mice expressing bovine PrP (30). Recently,
however, it has been reported that PrP-humanized mice inoculated with BSE
tissues may also propagate a distinctive PrPSc type, with a
”monoglycosylated-dominant” pattern and electrophoretic mobility of the
unglycosylated fragment slower than that of vCJD and BSE (31). Strikingly, this
PrPSc type shares its molecular properties with the a PrPSc molecule found in
classical sCJD. This observation is at variance with the PrPSc type found in
M/V2 sCJD cases and in cattle BASE, showing a monoglycosylated-dominant pattern
but faster electrophoretic mobility of the protease-resistant fragment as
compared with BSE. In addition to molecular properties of PrPSc, BASE and M/V2
sCJD share a distinctive pattern of intracerebral PrP deposition, which occurs
as plaque-like and amyloid-kuru plaques. Differences were, however, observed in
the regional distribution of PrPSc. While in M/V2 sCJD cases the largest amounts
of PrPSc were detected in the cerebellum, brainstem, and striatum, in cattle
BASE these areas were less involved and the highest levels of PrPSc were
recovered from the thalamus and olfactory regions.
In conclusion,
decoding the biochemical PrPSc signature of individual human and animal TSE
strains may allow the identification of potential risk factors for human
disorders with unknown etiology, such as sCJD. However, although BASE and sCJD
share several characteristics, caution is dictated in assessing a link between
conditions affecting two different mammalian species, based on convergent
biochemical properties of disease-associated PrPSc types. Strains of TSE agents
may be better characterized upon passage to transgenic mice. In the interim
until this is accomplished, our present findings suggest a strict
epidemiological surveillance of cattle TSE and sCJD based on molecular criteria.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC365745/
FC5.1.1
Transmission Results in Squirrel Monkeys Inoculated with
Human sCJD, vCJD, and GSS Blood Specimens: the Baxter Study
Brown, P1;
Gibson, S2; Williams, L3; Ironside, J4; Will, R4; Kreil, T5; Abee, C3 1Fondation
Alliance BioSecure, France; 2University of South Alabama, USA; 3University of
Texas MD Anderson Cancer Center, USA; 4Western General Hospital, UK; 5Baxter
BioSience, Austria
Background: Rodent and sheep models of Transmissible
Spongiform Encephalopathy (TSE) have documented blood infectivity in both the
pre-clinical and clinical phases of disease. Results in a (presumably more
appropriate) non-human primate model have not been reported.
Objective:
To determine if blood components (red cells, white cells, platelets, and plasma)
from various forms of human TSE are infectious.
Methods: Blood
components were inoculated intra-cerebrally (0.1 ml) and intravenously (0.5 ml)
into squirrel monkeys from 2 patients with sporadic Creutzfeldt- Jakob disease
(sCJD) and 3 patients with variant Creutzfeldt-Jakob disease (vCJD). Additional
monkeys were inoculated with buffy coat or plasma samples from chimpanzees
infected with either sCJD or Gerstmann-Sträussler-Scheinker disease (GSS).
Animals were monitored for a period of 5 years, and all dying or sacrificed
animals had post-mortem neuropathological examinations and Western blots to
determine the presence or absence of the misfolded prion protein (PrPTSE).
Results: No transmissions occurred in any of the animals inoculated with
blood components from patients with sporadic or variant CJD. All donor
chimpanzees (sCJD and GSS) became symptomatic within 6 weeks of their
pre-clinical phase plasmapheresis, several months earlier than the expected
onset of illness. One monkey inoculated with purified leukocytes from a
pre-clinical GSS chimpanzee developed disease after 36 months.
Conclusion: No infectivity was found in small volumes of blood
components from 4 patients with sporadic CJD and 3 patients with variant CJD.
***However, a single transmission from a chimpanzee-passaged strain of GSS shows
that infectivity may be present in leukocytes, and the shock of general
anaesthesia and plasmspheresis appears to have triggered the onset of illness in
pre-clinical donor chimpanzees.
Saturday, September 5, 2009
TSEAC MEETING FEBRUARY 12, 2004 THE BAXTER STUDY GSS
snip...
http://tseac.blogspot.com/2011/06/tseac-meeting-august-1-2011-donor.html
Saturday, September 5, 2009
TSEAC MEETING FEBRUARY 12, 2004 THE
BAXTER STUDY GSS
snip...
But the first thing is our own study,
and as I mentioned, it's a Baxter primate study, and those are the major
participants. And the goal was twofold, and here is the first one: to see
whether CJD, either sporadic or familial -- actually it turns out to be the
familial CJD is incorrect. It really should be the Fukuoka strain of
Gerstmann-Straussler-Scheinker disease. So it's really GSS instead of familial
CJD -- when passaged through chimps into squirrel monkeys using purified blood
components, very pure blood components.
So this addresses the question
that was raised just recently about whether or not red cell infectivity that's
been found in rodents is really in the red cells or is it contaminated.
We prepared these samples with exquisite care, and they are
ultra-ultra-ultra purified. There's virtually no contamination of any of the
components that we looked at ? platelets, red cells, plasma, white cells -- with
any other component.
These are a sort of new set of slides, and what
I've tried to do is make them less complicated and more clear, but I'm afraid I
haven't included the build. So you'll just have to try and follow what I explain
with this little red pointer.
There were three initial patients. Two of
them had sporadic CJD. One of them had Gerstmann-Straussler-Scheinker syndrome.
Brain tissue from each individual patient was inoculated intracerebrally into a
pair of chimpanzees. All right?
From those chimps, either plasma or
ultra purified -- in fact, everything is ultra-purified. I'll just talk about
purified plasma, purified white cells -- were inoculated intracerebrally and
intravenously to get the maximum amount of infective load into a pair of
squirrel monkeys.
The same thing was done for each of these three sets.
This monkey died from non-CJD causes at 34 months post inoculation.
Let
me go back for a second. I didn't point out the fact that these were not
sacrificed at this point. These chimpanzees were apheresed at 27 weeks when they
were still asymptomatic. In this instance, we apheresed them terminally when
they were symptomatic.
And before I forget, I want to mention just a
little sidelight of this. Chimpanzees in our experience -- and I think we may be
the only people that have ever inoculated chimpanzees, and that's no longer a
possibility, so this was 20, 30 years ago -- the shortest incubation period of
any chimpanzee that we have ever seen with direct intracerebral inoculation is
13 months.
So we chose 27 weeks, which is about seven months, and
incidentally typically the incubation period is more like 16 or 18 months. The
shortest was 13 months. We chose the 27th week, which is about six and a half
months, thinking that this would be about halfway through the incubation period,
which we wanted to check for the presence or absence of infectivity.
But
within four weeks after the apheresis, which was conducted under general
anesthesia for three or four hours apiece, every single one of the six
chimpanzees became symptomatic. That is another experiment that I would love to
conclude, perhaps because this is simply not heard of, and it very much smells
like we triggered clinical illness. We didn't trigger the disease, but it
certainly looks like we triggered symptomatic disease at a point that was much
earlier than one would have possibly expected.
Maybe it will never be
done because it would probably open the floodgates of litigation. There's no end
of little things that you can find out from CJD patients after the fact. For
example, the neighbor's dog comes over, barks at a patient, makes him fall down,
and three weeks later he gets CJD. So you have a lawsuit against the neighbor.
I mean, this is not an unheard of matter, but I do think that physical
stress in the form of anesthesia and four hours of whatever goes on with
anesthesia, low blood pressure, sometimes a little hypoxemia looks like it's a
bad thing.
So here we have the 31st week. All of the chimps are
symptomatic, and here what we did was in order to make the most use of the
fewest monkeys, which is always a problem in primate research, we took these
same three patients and these six chimps. Only now we pooled these components;
that is to say, we pooled the plasma from all six chimps. We pooled
ultra-purified white cells from all six chimps because here we wanted to see
whether or not we could distinguish a difference between intracerebral route of
infection and intravenous route of infection.
With respect to platelets
and red blood cells, we did not follow that. We inoculated both intracerebral
and intravenously, as we had done earlier because nobody has any information on
whether or not platelets and red cells are infectious, and so we wanted again to
get the maximum.
This is an IV versus IC goal. This one, again, is just
getting the maximum load in to see whether there is, in fact, any infectivity in
pure platelets, in pure red cells.
And of all of the above, the only
transmission of disease related to the inoculation was in a squirrel monkey that
received pure leukocytes from the presymptomatic apheresis. So that goes some
way to address the question as to whether or not it's a matter of contamination.
To date the red cells have not been -- the monkeys that receive red cells have
not been observed for more than a year because that was a later experiment.
So we still can't say about red cells, but we're about four and a half
years down the road now, and we have a single transmission from purified
leukocytes, nothing from plasma and nothing from platelets.
That was the
first part of the experiment. The second part was undertaken with the
cooperation of Bob Will and others supplying material to us. These were a couple
of human, sporadic cases of CJD and three variant cases of CJD from which we
obtained buffy coat and plasma separated in a normal way. That is, these are not
purified components.
The two cases of sporadic CJD, the plasma was
pooled from both patients. The buffy coat was pooled from both patients, and
then inoculated intracerebrally and intravenously into three squirrel monkeys
each. This is a non-CJD death five years after inoculation. The other animals
are still alive.
For variant CJD we decided not to pool. It was more
important to eliminate the possibility that there was just a little bit of
infectivity in one patient that would have been diluted to extinction, if you
like, by mixing them if it were to so occur with two patients, for example, who
did not have infectivity. So each one of these was done individually, but the
principle was the same: plasma and buffy coat for each patient was inoculated
into either two or three squirrel monkeys. This is, again, a non-CJD related
death.
In addition to that, we inoculated rain as a positive control
from the two sporadic disease cases of human -- from the two human sporadic
cases at ten to the minus one and ten to the minus three dilutions. We have done
this many, many times in the past with other sporadic patients. So we knew what
to expect, and we got exactly what we did expect, namely, after an incubation
period not quite two years, all four monkeys developed disease at this dilution
and at the minus three dilution, not a whole lot of difference between the two.
Now, these are the crucial monkeys because each one of these monkeys
every three to four months was bled and the blood transfused into a new healthy
monkey, but the same monkey all the time. So this monkey, for example, would
have received in the course of 21 months about six different transfusions of
blood from this monkey into this monkey, similarly with this pair, this pair,
and this pair. So you can call these buddies. This is sort of the term that was
used. These monkeys are still alive.
In the same way, the three human
variant CJD specimens, brain, were inoculated into four monkeys, and again, each
one of these monkeys has been repeatedly bled at three to four month intervals
and that blood transfused into a squirrel monkey, the same one each time.
Ideally we would love to have taken bleeding at three months and inoculated a
monkey and then let him go, watch him, and then done the same thing at six
months. It would have increased the number of monkeys eightfold and just
unacceptably expensive. So we did the best we could.
That, again, is a
non-CJD death, as is this.
This was of interest mainly to show that the
titer of infectivity in brain from variant CJD is just about the same as it from
sporadic. We didn't do a minus five and a minus seven in sporadic because we
have an enormous experience already with sporadic disease in squirrel monkeys,
and we know that this is exactly what happens. It disappears at about ten to the
minus five. So the brain titer in monkeys receiving human vCJD is identical to
the brain titer in monkeys that have been inoculated with sporadic CJD.
That's the experiment. All of the monkeys in aqua are still alive. They
are approaching a five-year observation period, and I think the termination of
this experiment will now need to be discussed very seriously in view of a
probable six-year incubation period in the U.K. case. The original plan was to
terminate the experiment after five years of observation with the understanding
that ideally you would keep these animals for their entire life span, which is
what we used to do when had unlimited space, money, and facilities. We can't do
that anymore.
It's not cheap, but I think in view of the U.K. case, it
will be very important to think very seriously about allowing at least these
buddies and the buddies from the sporadic CJD to go on for several more years
because although you might think that the U.K. case has made experimental work
redundant, in point of fact, anything that bears on the risk of this disease in
humans is worthwhile knowing, and one of the things we don't know is frequency
of infection. We don't know whether this case in the U.K. is going to be unique
and never happen again or whether all 13 or 14 patients have received blood
components are ultimately going to die. Let's hope not.
The French
primate study is primarily directed now by Corinne Lasmezas. As you know, the
late Dominique Dromont was the original, originally initiated this work, and
they have very active primate laboratory in France, and I'm only going to show
two very simple slides to summarize what they did.
The first one is
simply to show you the basis of their statement that the IV route of infection
looks to be pretty efficient because we all know that the intracerebral route of
infection is the most efficient, and if you look at this where they inoculated
the same infective load either intracerebrally or intravenously, the incubation
periods were not substantially different, which suggests but doesn't prove, but
doesn't prove that the route of infection is pretty efficient.
Lower
doses of brain material given IV did extend the incubation period and presumably
it's because of the usual dose response phenomenon that you see in any
infectious disease.
With a whopping dose of brain orally, the incubation
period was even lower. Again, just one more example of inefficiency of the route
of infection and the necessity to use more infective material to get
transmissions.
And they also have blood inoculated IV which is on test,
and the final slide or at least the penultimate slide shows you what they have
on test and the time of observation, that taken human vCJD and like us
inoculated buffy coat, they've also inoculated whole blood which we did not do.
So to a great extent their studies are complementary to ours and makes
it all worthwhile.
We have about -- oh, I don't know -- a one to
two-year lead time on the French, but they're still getting into pretty good
observation periods. Here's three-plus years.
They have variant CJD
adapted to the macaque. That is to say this one was passaged in macaque monkeys,
the cynomolgus, and they did the same thing. Again, we're talking about a study
here in which like ours there are no transmissions. I mean, we have that one
transmission from leukocytes, and that's it.
Here is a BSE adapted to
the macaque. Whole blood, and then they chose to inoculate leukodepleted whole
blood, in both instances IV. Here they are out to five years without a
transmission.
And then finally oral dosing of the macaque, which had
been infected with -- which was infected with BSE, but a macaque passaged BSE,
whole blood buffy coat and plasma, all by the IC route, and they're out to three
years.
So with the single exception of the leukocyte transmission from
our chimp that was inoculated with a sporadic case of CJD or -- excuse me --
with a GSS, Gerstmann-Straussler, in neither our study nor the French study,
which are not yet completed have we yet seen a transmission.
And I will
just close with a little cartoon that appeared in the Washington Post that I
modified slightly lest you get too wound up with these questions of the risk
from blood. This should be a "corrective."
(Laughter.)
DR.
BROWN: Thanks.
Questions?
CHAIRPERSON PRIOLA: Yes. Any questions
for Dr. Brown? Dr. Linden.
DR. LINDEN: I just want to make sure I
understand your study design correctly. When you mention the monkeys that have
the IV and IC inoculations, the individual monkeys had both or --
DR.
BROWN: Yes, yes, yes. That's exactly right.
DR. LINDEN: So an individual
monkey had both of those as opposed to some monkeys had one and some had the
other?
DR. BROWN: Correct, correct. Where IC and IV are put down
together was IC plus IV into a given monkey.
DR. LINDEN: Into a given
monkey. Okay.
And the IC inoculations, where were those given?
DR. BROWN: Right parietal cortex, Southern Alabama.
(Laughter.)
DR. BROWN: Oh, it can't be that clear. Yeah, here, Pierluigi.
CHAIRPERSON PRIOLA: Dr. Epstein.
DR. BROWN: Pierluigi always
damns me with feint praise. He always says that's a very interesting study, but.
I'm waiting for that, Pierluigi.
I think Jay Epstein --
DR.
GAMBETTI: I will say that there's an interesting study and will say, but I just
--
(Laughter.)
DR. GAMBETTI: -- I just point of review. You talk
about a point of information. You say that -- you mention GSS, I guess, and the
what, Fukuowa (phonetic) --
DR. BROWN: Yes, Fukuoka 1.
DR.
GAMBETTI: Fukuowa, and is that from the 102, if I remember correctly, of the --
DR. BROWN: Yes, that is correct.
DR. GAMBETTI: Because that is
the only one that also --
DR. BROWN: No, it's not 102. It's 101. It's
the standard. It's a classical GSS. Oh, excuse me. You're right. One, oh, two is
classical GSS. It's been so long since I've done genetics. You're right.
DR. GAMBETTI: Because that is the only one I know, I think, that I can
remember that has both the seven kv fragment that is characteristic of GSS, but
also the PrPsc 2730. So in a sense, it can be stretching a little bit compared
to the sporadic CJD.
DR. BROWN: Yeah, I think that's right. That's why I
want to be sure that I made you aware on the very first slide that that was not
accurate, that it truly was GSS.
There's a GSS strain that has been
adapted to mice, and it's a hot strain, and therefore, it may not be
translatable to sporadic disease, correct. All we can say for sure is that it is
a human TSE, and it is not variant. I think that's about it.
DR.
GAMBETTI: I agree, but this is also not perhaps the best --
DR. BROWN:
No, it is not the best. We understand --
DR. GAMBETTI: -- of GSS either.
DR. BROWN: Yeah. If we had to do it over again, we'd look around for a
-- well, I don't know. We'd probably do it the same way because we have two
sporadics already on test they haven't transmitted, and so you can take your
pick of what you want to pay attention to.
Jay?
DR. EPSTEIN:
Yes, Paul. Could you just comment? If I understood you correctly, when you did
the pooled apheresis plasma from the six chimps when they were symptomatic at 31
weeks, you also put leukocytes into squirrel monkeys in that case separately IV
and IC, but in that instance you have not seen an infection come down in
squirrel monkey, and the question is whether it's puzzling that you got
transmission from the 27-week asymptomatic sampling, whereas you did not see
transmission from the 31-week sampling in symptomatic animals.
DR.
BROWN: Yes, I think there are two or three possible explanations, and I don't
know if any of them are important. The pre-symptomatic animal was almost
symptomatic as it turned out so that we were pretty close to the period at which
symptoms would being, and whether you can, you know, make much money on saying
one was incubation period and the other was symptomatic in this particular case
because both bleedings were so close together. That's one possibility.
The other possibility is we're dealing with a very irregular phenomenon
and you're not surprised at all by surprises, so to speak so that a single
animal, you could see it almost anywhere.
The third is that we, in fact,
did just what I suggested we didn't want to do for the preclinical, namely, by
pooling we got under the threshold. See?
You can again take that for
what it's worth. It is a possible explanation, and again, until we know what the
levels of infectivity are and whether by pooling we get under the threshold of
transmission, we simply cannot make pronouncements.
CHAIRPERSON PRIOLA:
Dr. DeArmond.
DR. DeARMOND: Yeah, it was very interesting data, but the
--
(Laughter.)
DR. BROWN: I just love it. Go ahead.
DR.
DeARMOND: Two comments. The first one was that the GSS cases, as I remember from
reading your publications -- I think Gibbs was involved with them -- when you
transmitted the GSS into animals, into monkeys, perhaps I think it was chimps,
the transmission was more typical of CJD rather than GSS. There were no amyloid
plaques. It was vacuolar degeneration so that you may be transmitting a peculiar
form, as I criticized once in Bali and then you jumped all over me about.
DR. BROWN: I may do it again.
DR. DeARMOND: Calling me a bigot
and some other few things like that.
(Laughter.)
DR. BROWN:
Surely not. I wouldn't have said that.
DR. DeARMOND: So there could be
something strange about that particular --
DR. BROWN: Yeah. I think you
and Pierluigi are on the same page here. This may be an unusual strain from a
number of points of view.
DR. DeARMOND: The other question though has to
do with species barrier because the data you're showing is kind of very
reassuring to us that it's hard to transmit from blood, but the data from the
sheep and from the hamsters and some of the work, I think, that has been done by
others, that it's easy in some other animals to transmit, hamster to hamster,
mouse to mouse.
Could you comment on the --
DR. BROWN: That's
exactly why we went to primates. That's exactly it, because a primate is closer
to a human than a mouse is, and that's just common sense.
And so to try
and get a little closer to the human situation and not totally depend on rodents
for transferrable data, that is why you would use a primate. Otherwise you
wouldn't use them. They're too expensive and they cause grief to animal care
study people and protocol makers and the whole thing.
Primate studies
are a real pain.
DR. DeARMOND: But right now it's inconclusive and you
need more time on it.
DR. BROWN: I believe that's true. I think if we
cut it off at six years you could still say it was inconclusive, and cutting it
off at all will be to some degree inconclusive, and that's just the way it is.
DR. DeARMOND: So what has to be done? Who do you have to convince, or
who do we all have to convince to keep that going?
DR. BROWN: Thomas?
Without trying to be flip at all, the people that would be the first
people to try to convince would be the funders of the original study. If that
fails, and it might for purely practical reasons of finance, then we will have
to look elsewhere because I really don't want to see those animals sacrificed,
not those eight buddies. Those are crucial animals, and they don't cost a whole
lot to maintain. You can maintain eight -- well, they cost a lot from my point
of view, but 15 to $20,000 a year would keep them going year after year.
CHAIRPERSON PRIOLA: Dr. Johnson.
DR. JOHNSON: Yeah, Paul, I'm
intrigued as you are by the shortening of the incubation period. Have you in all
of the other years of handling these animals when they were transfused, when
they were flown out to Louisiana at night -- a lot of the stressful things have
happened to some of these chimps. Have you ever noticed that before or is this a
new observation?
DR. BROWN: Brand new.
MR. JOHNSON: Brand new.
Okay.
CHAIRPERSON PRIOLA: Bob, did you want to say something? Dr.
Rohwer.
DR. ROHWER: The Frederick fire, wasn't that correlated with a
lot of --
DR. BROWN: Not that I k now of, but you may --
DR.
ROHWER: Well, that occurred shortly after I came to NIH, and what I remember is
that there were a whole bunch of conversions that occurred within the few months
following the fire. That was fire that occurred adjacent to the NINDS facility,
but in order to protect it, they moved the monkeys out onto the tarmac because
they weren't sure it wouldn't burn as well.
DR. BROWN: Well, if you're
right, then it's not brand new, but I mean, I'm not sure how we'll ever know
because if I call Carlton and ask him, I'm not sure but what I would trust the
answer that he gives me, short of records.
You know, Carlot is a very
enthusiastic person, and he might say, "Oh, yeah, my God, the whole floor died
within three days," but I would want to verify that.
On the other hand,
it may be verifiable. There possibly are records that are still extant.
DR. ROHWER: Actually I thought I heard the story from you.
(Laughter.)
DR. BROWN: You didn't because it's brand new for me.
I mean, either that or I'm on the way
(Laughter.)
CHAIRPERSON
PRIOLA: Dr. Bracey.
DR. BRACEY: I was wondering if some of the
variability in terms of the intravenous infection route may be related to
intraspecies barriers, that is, the genetic differences, the way the cells, the
white leukocytes are processed, whether or not microchimerism is established, et
cetera.
DR. BROWN: I don't think that processing is at fault, but the
question, the point that you raise is a very good one, and needless to say, we
have material with which we can analyze genetically all of the animals, and
should it turn out that we get, for example, -- I don't know -- a transmission
in one variant monkey and no transmissions in another and a transmission in
three sporadic monkeys, we will at that point genetically analyze every single
animal that has been used in this study, but we wanted to wait until we could
see what would be most useful to analyze.
but the material is there, and
if need be, we'll do it.
CHAIRPERSON PRIOLA: Okay. Thank you very much,
Dr. Brown.
I think we'll move on to the open public hearing section of
the morning.
snip...
http://www.fda.gov/ohrms/dockets/ac/04/transcripts/4019t1.DOC
snip...
see full text ;
http://tseac.blogspot.com/2009/09/tseac-meeting-february-12-2004-baxter.html
(Laughter.)
Saturday, January 20, 2007
Fourth case of
transfusion-associated vCJD infection in the United Kingdom
http://vcjdtransfusion.blogspot.com/2007/01/fourth-case-of-transfusion-associated.html
(Laughter.)
Friday, June 29, 2012
Highly Efficient
Prion Transmission by Blood Transfusion
http://transmissiblespongiformencephalopathy.blogspot.com/2012/06/highly-efficient-prion-transmission-by.html
(Laughter.)
Wednesday, August 24, 2011
All
Clinically-Relevant Blood Components Transmit Prion Disease following a Single
Blood Transfusion: A Sheep Model of vCJD
http://transmissiblespongiformencephalopathy.blogspot.com/2011/08/all-clinically-relevant-blood.html
(Laughter.)
Sunday, July 20, 2008
Red Cross told to
fix blood collection or face charges 15 years after warnings issued, few changes
made to ensure safety
http://vcjdblood.blogspot.com/2008/07/red-cross-told-to-fix-blood-collection.html
Saturday, December 08, 2007
Transfusion Transmission of Human
Prion Diseases
http://vcjdblood.blogspot.com/2006/12/vcjd-case-study-highlights-blood.html
Tuesday, October 09, 2007
nvCJD TSE BLOOD UPDATE
http://vcjdblood.blogspot.com/2007/10/nvcjd-tse-blood-update.html
Saturday, December 08, 2007
Transfusion Transmission of Human
Prion Diseases
http://vcjdblood.blogspot.com/2007/12/transfusion-transmission-of-human-prion.html
Saturday, January 20, 2007
Fourth case of
transfusion-associated vCJD infection in the United Kingdom
http://vcjdtransfusion.blogspot.com/2007/01/fourth-case-of-transfusion-associated.html
vCJD case study highlights blood transfusion risk 9 Dec 2006 by Terry
S. Singeltary Sr.
THIS was like closing the barn door after the mad cows
got loose. not only the red cross, but the FDA has failed the public in
protecting them from the TSE aka mad cow agent. TSE agent ie bse, base, cwd,
scrapie, tme, ...
vCJD case study highlights blood transfusion risk -
http://www.mrc.ac.uk/Newspublications/News/MRC003431
http://vcjdblood.blogspot.com/2006/12/vcjd-case-study-highlights-blood.html
http://vcjdblood.blogspot.com/
Friday, April 19, 2013
APHIS 2013 Stakeholder Meeting (March
2013) BSE TSE PRION
http://madcowusda.blogspot.com/2013/04/aphis-2013-stakeholder-meeting-march.html
