Prion disease
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GG Glenner was right: yeast prions URE3 and Sup35 are congo red birefringent
Structure of SH3 cross beta fibril
Surgery increases risk of sporadic CJD
14-3-3 suffices for CJD diagnosis, neuron-specific enolase, S-100 not needed
Met/met at 129 predisposes to sporadic inclusion-body myositis
Scrapie and knockout mice: abnormal localization and activity of nNOS.
D178N: first Austrian kindred
Laminin binds another amyloid former, serum amyloid A.
Novel epitope for specific detection of exogenous prion protein
Risk of nvCJD in Blood: DNV assessment
TSE regulation in Germany a muddle
Scientists fight for right to withhold data

Surgery increases risk of sporadic CJD

BMJ 1999;318:625  6•March 99 free full-text by Zosia•Kmietowicz 
Surgery could be the leading risk factor for the development of the sporadic form of Creutzfeldt-Jakob disease (CJD), suggests an Australian study showing that people who have had more than three operations are twice as likely to contract the disease as those who have had no surgery.

The finding comes from a study carried out by the Australian National Creutzfeldt-Jakob Disease Registry at the University of Melbourne, designed to identify the risk factors for sporadic CJD (Lancet 1999; 353:693-7). The cause of sporadic CJD is unknown, whereas new variant CJD is linked to bovine spongiform encephalopathy (BSE) and is specific to the United Kingdom. Although very rare, occurring at a rate of about one in a million throughout the world, sporadic CJD is the more common of the two types of disease and accounts for about 85-90%of all cases.

The Australian study compared the medical history and characteristics of 241•definite and probable cases of CJD that occurred between 1970•and 1997,•with 784•volunteers matched as case controls. They found a significant association between surgical procedures and the development of sporadic CJD. This risk increased with the number of surgical treatments, doubling in people undergoing more than three operations from one in a million to two in a million.

Another risk factor linked to increased risk of sporadic CJD was residence or employment on a farm or market garden for more than 10•years. Blood transfusions, organ transplantation, and major dental work were not linked to increased risk.

Professor Colin Masters, who heads the Australian registry, said that the group was still uncertain how surgical episodes may cause contamination leading to increased risk of sporadic CJD. He speculated that dental work carried negligible risk of transmitting infection because it involved minimal exposure to infectious tissue.

Commenting on the implications of the findings, Professor Masters concluded: "Our research indicates that continual vigilance in the hospital setting may be important in reducing the risk of sporadic CJD."

Surgical treatment and risk of sporadic CJD: a case-control study.

Lancet 1999 Feb 27;353(9154):693-7 
Collins S, Law MG, Fletcher A, Boyd A, Kaldor J, Masters CL
Apart from the small number of iatrogenic and familial cases, the cause of most cases of Creutzfeldt-Jakob disease (CJD) is not known. We aimed to identify risk factors for sporadic CJD. In a case-control study, we compared the medical history and selected demographic characteristics of 241 definite (neuropathologically confirmed) and probable (clinically likely) patients with CJD, ascertained from the Australian National Creutzfeldt-Jakob Disease Registry between Jan 1, 1970, and October 31, 1997, and of 784 controls, recruited from the community by random telephone interview in August, 1997. Standard logistic regression was used for the comparisons.

Surgical procedures were significantly associated with the development of sporadic CJD. This risk progressively increased with the number of surgical treatments to a maximum for three procedures (odds ratio 2.13 [95% Cl 1.34-3.41], p=0.002). There was also a significant association between risk of CJD and residence or employment on a farm (p<0.001) or market garden (p=0.002) for longer than 10 years. We found no significant risk associated with a history of blood transfusion, organ transplantation, major dental work, or occupation.

Our findings accord with the hypothesis that a range of surgical treatments may serve as unrecognised contamination events and account for a proportion [why not tell us what proportion your data suggesst? -- webmaster] of cases of sporadic CJD. Possible biases in different methods and times for the acquisition of data on cases and controls suggest our findings need to be replicated in independent studies with community controls.

Met/met at 129 may predispose to sporadic inclusion-body myositis

6 Feb 98 Lancet
Johannes Lampe, Hagen Kitzler, Maggie C Walter, Hanns Lochm‡ller, Heinz Reichmann
Comment (webmaster): Given the previous work on the role of the prion protein in this disease, the news here would be met/met fibers are formed more readily or turned over more slowly than val/val. Inclusion-body myositis could be a chaperone over/under expression disorder, as seen in yeast. This paper suggests that the ascertainment of the disease may be favored when the prion protein is this allele (as in sporadic CJD). The same thing was observed years ago with apolipoprotein E type epsilon 4. IBMD is probably not directly related to loss of normal prion function.

The article itself is half a page. They looked at 22 cases of sIBM and 57 controls. 14 were met/met (64%); 1 val/val, and 7 met/val. Using a chi-squared test, they conclued met/met was over-represented (p=0.023). They did a good job of compiling normal met/met frequencies which run consistently at 40% in Europeans. The number of patients is too small to say whether val/val is enhanced over met/val, as expected from the like-like parinciple and sporadic CJD.

Fourteen newly recognized proteins at the human neuromuscular junctions--and their nonjunctional accumulation in inclusion-body myositis.

Ann N Y Acad Sci 1998 May 13;841:28-56 no abstract available
Askanas V, Engel WK, Alvarez RB
Inclusion body myositis (IBM) is a very thought-provoking disorder. I looked at the full text of some earlier papers. 14 different neuromuscular junction proteins accumulate when things go bad. It is like having both CJD and Alzheimer but within muscle fibers. No one has tested this muscle fiber directly for infectivity nor even strain-typed the fibrils (which are however proteaese K resistant and congophilic). FIBM maps to a 1-Mb interval on human chromosome 9 between D9S1791 and D9S50 and possibly encode a novel muscle or junctional regulatory protein; beta-tropomyosin is nearby but excluded. The over-production in FIBM could be primary or a result of feedback from proteins not reaching their targeted destination.

The disease is not known in livestock but it is expected at roughly the same (poorly know) incidence. A similar myopathy is found in transgenic mice expressing high levels of normal PrP. [Curr Opin Neurol 1993 Dec;6(6):872-81] Recycling of meat byproducts within a species has potential for amplifying disease, as do surgical procedures.

The 14 proteins that accumulate are normally found post-synaptically and intra-cellularly at the neuromuscular junction; prion protein is clearly a normal component of muscle fiber. In the sporadic and heriditary forms of IBM, the 14 proteins are over-produced [more prion mRNA etc.] and accumulate as congophilic aggregates but not at their normal junctional site.

The 14 proteins are:

prion protein
beta amyloid protein
beta amyloid precursor protein N- and C- terminal variants
alpha-1 antichymotrypsin [Abeta1-42 intercalates in its beta sheets]
hyperphosphorylated tau
apolipoprotein E
superoxide dismutase 1
ubiquitin
neural nitric oxide synthase
inducible nitric oxide synthase
nicotinic acetlycholine receptor
fibroblast growth factor
transforming growth factor beta-1
rapsyn
interleukin 1-alpha
interleukin 1-beta
interleukin 6

Prion protein is abnormally accumulated in inclusion-body myositis.

Neuroreport 1993 Oct 25;5(1):25-8 
Askanas V, Bilak M, Engel WK, Alvarez RB, Tome F, Leclerc A
In muscle biopsies of 8 sporadic inclusion-body myositis (S-IBM) and 4 hereditary inclusion-body myopathy (H-IBM) patients, vacuolated muscle fibers contained within their vacuoles strongly immunoreactive inclusions with 2 polyclonal and 1 monoclonal antibodies against prion protein (PrP). By light-microscopy, PrP deposits co-localized with beta-amyloid protein (A beta) and ubiquitin (Ub). By immuno-electronmicroscopy, both PrP and A beta were present on amorphous material and on 6-10 nm amyloid-like fibrils; and PrP and Ub co-localized on cytoplasmic twisted tubulofilaments (TTFs) and on amorphous material. Our study provides the first demonstration of abnormally accumulated PrP in pathological tissue other than brain, and it suggests that PrP may play a role in the pathogenesis of IBM.

Abnormal accumulation of prion protein mRNA in muscle fibers of patients with sporadic inclusion-body myositis and hereditary inclusion-body myopathy.

Am J Pathol 1994 Dec;145(6):1280-4 
Sarkozi E, Askanas V, Engel WK
Sporadic inclusion-body myositis is the most common progressive muscle disease of older patients. The muscle biopsy demonstrates mononuclear cell inflammation and vacuolated muscle fibers containing paired helical filaments and 6 to 10-nm fibrils, both resembling those of Alzheimer brain, and Congo-red positivity. Hereditary inclusion-body myopathy designates patients cytopathologically similar but without inflammation. In both muscle diseases, prion, and several proteins characteristic of Alzheimer brain--eg, beta-amyloid protein and hyperphosphorylated tau (which normally are expressed mainly in neurons), and apolipoprotein E--are abnormally accumulated in vacuolated muscle fibers, by unknown mechanisms. We now demonstrate in both muscle diseases that prion mRNA is strongly expressed in the vacuolated muscle fibers, which suggests that their accumulated prion protein results, at least partly, from increased gene expression. This, to our knowledge, is the first demonstration of abnormally increased prion mRNA in human disease. Another novel finding is the increased prion mRNA in human muscle macrophages, and both increased prion protein and prion mRNA in regenerating muscle fibers. The latter indicates that prion may play a role in human muscle development.

Alzheimer's disease and Creutzfeldt-Jakob disease: overlap of pathogenic mechanisms.

Curr Opin Neurol 1993 Dec;6(6):872-81 
DeArmond SJ 
This article compares beta-amyloid precursor protein (beta-APP) disorders exemplified by Alzheimer's disease (AD), with prion protein (PrP) disorders, exemplified by Creutzfeldt-Jakob disease (CJD) in humans and scrapie in animals. Although there are obvious differences in the etiology and pathogenesis of both sets of disorders, a remarkable number of similarities exist. Both sets of disorders are characterized clinically by age-related sporadic and familial diseases. In both, an abnormal form of a neuronal membrane protein appears to play a key role in the pathogenesis: beta-A4 peptide in AD and PrPCJD in CJD. Both beta-A4 and PrPCJD are amyloidogenic. Neuritic plaques characteristic of AD were once thought to be exclusively associated with beta-A4 amyloid; however, some pedigrees with familial prion disease produced neuritic plaques with PrP amyloid cores. Finally, beta-APP accumulation in skeletal muscle has been implicated in the age-related muscle disorder, inclusion body myositis. A similar myopathy has recently been discovered in transgenic mice expressing high levels of normal PrP [Westaway et al. however do not mention IBM]]

Inclusion body myositis--a review.

Adv Anat Pathol 1998 May;5(3):164-9 
Vogel H 
Inclusion body myositis (IBM), a sporadic inflammatory myopathy, is the most frequently occurring progressive myopathy in adults older than 55 years. It more commonly affects men and usually is clinically and pathologically distinguishable from dermatomyositis or polymyositis. Muscle biopsy specimens will display inflammation in virtually all cases of sporadic IBM, along with rimmed vacuoles accompanied by the accumulation of beta-amyloid and other substances similar to those found in the degenerating neurons of Alzheimer's disease. The similarities between IBM and other inflammatory myopathies may contribute to its low level of diagnosis by pathologists. The proper recognition of IBM is important because, unlike other inflammatory myopathies, IBM is unresponsive to anti-inflammatory drugs.

Sporadic inclusion-body myositis and its similarities to Alzheimer disease brain. Recent approaches to diagnosis and pathogenesis, and relation to aging.

Scand J Rheumatol 1998;27(6):389-405 
Askanas V, Engel WK
Sporadic inclusion-body myositis (s-IBM) is the most common, debilitating and progressive muscle disease beginning at the age 50 or later. The most characteristic pathologic feature is vacuolar degeneration of muscle fibers accompanied by intrafiber congophilia and clusters ("tangles") of paired-helical filaments, containing phosphorylated tau. An unusual feature of sporadic inclusion-body myositis is accumulation within its abnormal muscle fibers of several proteins that are characteristic of Alzheimer disease brain, including epitopes of beta-amyloid precursor protein (betaAPP), phosphorylated tau, alpha-1-antichymotrypsin, apolipoprotein E, and presenilin-1. Indicators of oxidative stress are also present within abnormal s-IBM muscle fibers.... We present evidence that overexpression of adenovirus-transferred betaAPP gene in cultured human muscle fibers induces aspects of the inclusion-body myositis phenotype, and suggest that betaAPP-overexpression is an early event in the pathogenic cascade causing inclusion-body myositis.

Genetics of inclusion body myopathies.

Argov Z, Eisenberg I, Mitrani-Rosenbaum S
Curr Opin Rheumatol 1998 Nov;10(6):543-7
We review the current knowledge about the genetic susceptibility to develop inflammatory inclusion body myositis, especially in relation to the increased presence of the HLA DR3 allele in patients with familial and sporadic forms, indicating an autoimmune predisposition. The main focus of the review is the clinical and genetic presentations of the various hereditary inclusion body myopathies. Criteria for diagnosis and classification of these myopathies are presented. The spectrum of the recessive forms of hereditary inclusion body myopathies currently linked to chromosome 9p1-q1 is described, with emphasis on the up-to-date status of the gene search for these forms.

Sporadic inclusion-body myositis and hereditary inclusion-body myopathies: current concepts of diagnosis and pathogenesis.

Curr Opin Rheumatol 1998 Nov;10(6):530-42 
Askanas V, Engel WK 
A classification of the various h-IBM syndromes is presented. The several forms of the h-IBMs have different genetic transmissions and probably different genetic defects. In neither s-IBM nor the h-IBMs are the sequential steps of the pathogenic cascade understood. Because s-IBM and the h-IBMs have a number of characteristic pathologic features in common, we postulate that their different causes trigger the same upstream aberration leading to a similar downstream cascade of pathologic events, which are ultimately responsible for the characteristic muscle-fiber degeneration. Muscle-biopsy and experimental evidence is given supporting our hypothesis that overexpression of beta-amyloid precursor protein within abnormal muscle fibers is an early upstream event causing the pathogenic cascade. We also present evidence supporting our concept that muscle aging and oxidative stress are important factors contributing to the s-IBM-specific muscle fiber destruction. Additionally, the intriguing parallels between the pathologic phenotype of IBM muscle fibers and Alzheimer's disease brain are summarized.

Light and electron microscopic immunolocalization of presenilin 1 in abnormal muscle fibers of patients with sporadic inclusion-body myositis and autosomal-recessive inclusion-body myopathy.

Am J Pathol 1998 Apr;152(4):889-95 
Askanas V, Engel WK, Yang CC, Alvarez RB, Lee VM, Wisniewski T
Sporadic inclusion-body myositis (s-IBM) is the most common progressive muscle disease of older persons. The muscle biopsy demonstrates mononuclear cell inflammation and vacuolated muscle fibers containing paired helical filaments and 6- to 10-nm fibrils, both resembling those of Alzheimer disease brain and Congo red positivity. The term hereditary inclusion-body myopathies (h-IBMs) designates autosomal-recessive or autosomal-dominant disorders with muscle biopsies cytopathologically similar to s-IBM but without inflammation. Vacuolated muscle fibers of both s-IBM and the h-IBMs contain accumulations of several "Alzheimer-characteristic proteins" including beta-amyloid protein and beta-amyloid precursor protein, and their paired helical filaments are composed of phosphorylated tau. We used six well characterized antibodies against several residues of presenilin 1 (PS1) to immunostain muscle biopsies of 12 patients with s-IBM, 5 patients with autosomal-recessive inclusion-body myopathy, and 16 normal and disease controls. Seventy to eighty percent of the vacuolated muscle fibers of both s-IBM and autosomal-recessive inclusion-body myopathy had inclusions that were strongly PS1-immunoreactive, which by immunoelectron microscopy localized mainly to paired helical filaments and 6- to 10-nm filaments. None of the control biopsies had PS1-positive inclusions characteristic of the s- and h-IBM abnormal muscle fibers. Mutations of the newly discovered PS1 gene are responsible for early-onset familial Alzheimer disease (AD), and PS1 is abnormally accumulated in sporadic and familial AD brain. Our study provides the first demonstration of PS1 abnormality in non-neural tissue and in diseases other than AD and suggests that the cytopathogenesis in AD brain and IBM muscle may share similarities.

Apolipoprotein E and apolipoprotein E messenger RNA in muscle of inclusion body myositis and myopathies.

Ann Neurol 1996 Dec;40(6):864-72 
Mirabella M, Alvarez RB, Engel WK, Weisgraber KH, Askanas V  
Sporadic inclusion body myositis and the hereditary inclusion body myopathies are severe, progressive muscle diseases, characterized pathologically by vacuolated muscle fibers containing paired helical filaments. We immunostained muscle biopsy specimens from sporadic inclusion body myositis, hereditary inclusion body myopathy, disease control, and normal patients with several antibodies against apolipoprotein E (ApoE). Approximately 80 to 90% of the vacuolated muscle fibers of sporadic inclusion body myositis contained well-defined, strongly immunoreactive ApoE inclusions. In hereditary inclusion body myopathy, only rare vacuolated fibers had immunoreactive inclusions, whereas most had diffuse cytoplasmic ApoE immunoreactivity. Ultrastructurally, ApoE immunoreactivity in sporadic myositis was localized mainly to the paired helical filaments. By contrast, in the hereditary form, ApoE immunoreactivity occurred on material in close proximity to the paired helical filaments, but never was on the paired helical filaments. In both muscle diseases, ApoE was also on the 6- to 10-nm filaments and amorphous material. In the sporadic form, ApoE-immunoreactive deposits colocalized with Congo red-positive deposits; however, in muscle fibers from patients with hereditary disease there was no congophilia. ApoE messenger RNA was not detectable in muscle fibers from patients with hereditary or sporadic disease but was expressed abundantly in muscle macrophages. In all control and inclusion body myositis or myopathy biopsy specimens, ApoE immunoreactivity was strong at the postsynaptic domain of neuromuscular junctions; nonjunctional regions of normal fibers were negative for ApoE. ApoE immunoreactivity occurred diffusely in regenerating muscle fibers, a subset of which had detectable ApoE messenger RNA.

New advances in the understanding of sporadic inclusion-body myositis and hereditary inclusion-body myopathies.

Curr Opin Rheumatol 1995 Nov;7(6):486-96
Askanas V, Engel WK 
This review emphasizes new advances in seeking the pathogenic mechanisms of sporadic inclusion-body myositis and hereditary inclusion-body myopathy syndromes. Clinical and pathologic similarities and differences between sporadic and hereditary forms are described. Hypotheses are presented regarding the possible causes and consequences of abnormally accumulated intramyofiber beta-amyloid precursor protein (beta APP) (including beta-amyloid protein and C- and N-terminal epitopes), hyperphosphorylated tau, alpha 1-antichymotrypsin, apolipoprotein E, prion protein, ubiquitin, nicotinic acetylcholine receptor and its 43-kD associated protein, fibroblast growth factor, and transforming growth factor-beta. Also increased are beta APP mRNA and prion protein mRNA. Striking similarities between the pathology of muscle specimens from sporadic inclusion-body myositis and samples from the brains of patients with Alzheimer's disease in regard to Congo red positivity and accumulations of several proteins are discussed. Because most of the proteins that pathologically accumulate throughout the abnormal muscle fibers also accumulate focally at normal human neuromuscular junctions, the possible "junctionalization" of nonjunctional nuclei as a pathogenic mechanism in the muscle fiber is discussed.

Amyloidosis causing a progressive myopathy.

Muscle Nerve 1995 Sep;18(9):1016-8 
Nadkarni N, Freimer M, Mendell JR 
A 62-year-old woman developed profound weakness secondary to a progressive myopathy associated with primary systemic amyloidosis. The characteristic apple-green birefringent amyloid deposits were demonstrated surrounding individual muscle fibers in Congo red stained sections. Electron microscopy demonstrated amyloid filaments in close apposition to muscle fibers exhibiting excessive corrugations of the sarcolemmal membrane. The pathological features of progressive amyloid myopathy associated with primary systemic amyloidosis are distinct from the intracellular amyloid deposits characteristic of sporadic inclusion body myositis and inherited inclusion body myopathy.

Apolipoprotein E type epsilon 4 allele frequency is not increased in patients with sporadic inclusion-body myositis.

Neurosci Lett 1995 Jan 2;183(1-2):35-8 Harrington CR, Anderson JR, Chan KK The apolipoprotein E genotype was determined for 11 patients with sporadic inclusion-body myositis. Seven cases had the genotype epsilon 3/epsilon 3, the other four cases, epsilon 3/epsilon 4. The frequency of the epsilon 4 allele in this group of patients (0.182) was not significantly increased compared with elderly controls (0.147; n = 58), in contrast to Alzheimer's disease in which there was a significant increase (0.328; n = 67). The epsilon 2 allele was not found in any of the 11 sporadic inclusion-body myositis patients and its frequency was decreased in Alzheimer's disease. Despite certain pathological similarities that exist between inclusion body myositis and Alzheimer's disease, their association with particular apolipoprotein E genotypes is distinct.

Idiopathic inflammatory myopathies: inclusion-body myositis, polymyositis, and dermatomyositis.

Curr Opin Neurol 1994 Oct;7(5):448-56 
Askanas V, Engel WK, Mirabella M
In this review, the main emphasis is on new advances concerning sporadic inclusion-body myositis and hereditary inclusion-body myopathy. Polymyositis and dermatomyositis are reviewed briefly. Hypotheses are presented regarding the possible cause and significance of abnormally accumulated beta-amyloid protein, two other epitopes of beta-amyloid precursor protein, hyperphosphorylated tau, alpha 1-antichymotrypsin, ubiquitin, and prion protein in sporadic inclusion-body myositis and hereditary inclusion-body myopathy. Because most of those proteins are also accumulated at the neuromuscular junction, "junctionalization" of other muscle fiber nuclei is a possibility. Attention is given to the fact that vacuolated muscle fibers in hereditary inclusion-body myopathy may represent early changes because they are virtually free of congophilic amyloid deposit but, like sporadic inclusion-body myositis, contain large accumulations of beta-amyloid protein and prion.

Amyloid filaments in inclusion body myositis. Novel findings provide insight into nature of filaments.

Arch Neurol 1991 Dec;48(12):1229-34 
Mendell JR, Sahenk Z, Gales T, Paul L 
Inclusion body myositis (IBM) represents a serious debilitating disease of muscle without identifiable cause or treatment. Muscle biopsy specimens have characteristic rimmed vacuoles, varying degrees of inflammation, and, most importantly, cytoplasmic and intranuclear filamentous inclusions of unknown composition. Fresh-frozen sections of muscle biopsy specimens from 24 IBM cases were stained with Congo red dye (pH, 10.5 to 11.0). Control biopsy specimens included polymyositis, dermatomyositis, hereditary vacuolar myopathies of unknown cause, acid maltase deficiency, distal myopathy, oculopharyngeal dystrophy, and chloroquine myopathy. Sections were also immunostained with antibody to transthyretin, human P component, and immunoglobulin light chains. In the vacuolated fibers in IBM, amyloidogenic green-birefringent deposits were seen. Some deposits were delicate and wispy appearing, and others were plaque-like. The size of deposits varied, measuring 1 x 2 to 8 microns, and rarely up to 20 microns in length. The number of amyloid-positive fibers correlated with the number of vacuolated fibers.

Similar deposits were seen in one case of distal myopathy and one hereditary vacuolar myopathy. Other control cases were negative for amyloid deposits. Antibody staining for known amyloidogenic proteins was negative. This study demonstrates that the filaments in IBM share properties with amyloid proteins. The location implies that this amyloid material is formed intracellularly, rather than having a systemic derivation. The association of amyloid deposits with autophagic vacuoles in IBM raises the likely possibility that the filaments represent a modification of a normal protein within an acidic degradative vacuolar compartment. An alternative possibility, considering the shared properties of IBM filaments and prions (which include size and amyloidogenic properties), is that IBM represents a human prion disease.

The URE3 prion is an aggregated form of Ure2p that can be cured by overexpression of Ure2p fragments

PNAS Vol. 96, Issue 4, 1498-1503, February 16, 1999
Herman K. Edskes, Vaughn T. Gray, and Reed B. Wickner
The URE3 nonchromosomal genetic element is a prion of Ure2p, a regulator of nitrogen catabolism in Saccharomyces cerevisiae. Ure2p1-65 is the prion domain of Ure2p, sufficient to propagate URE3 in vivo. We show that full length Ure2p-green fluorescent protein (GFP) or a Ure2p1-65-GFP fusion protein is aggregated in cells carrying URE3 but is evenly distributed in cells lacking the URE3 prion. This indicates that URE3 involves a self-propagating aggregation of Ure2p. Overexpression of Ure2p1-65 induces the de novo appearance of URE3 by 1,000-fold in a strain initially [ure-o], but cures URE3 from a strain initially carrying the URE3 prion. Overexpression of several other fragments of Ure2p or Ure2-GFP fusion proteins also efficiently cures the prion. We suggest that incorporation of fragments or fusion proteins into a putative URE3 "crystal" of Ure2p poisons its propagation.

Yeast cells grown on a rich source of nitrogen, such as ammonia, repress transcription of genes needed for using a poor nitrogen source. Ure2p mediates this "nitrogen catabolite repression" by blocking the positive transcription regulator, Gln3p. Among the genes so regulated is Dal5p, a transporter for allantoate, a poor but usable nitrogen source. Ureidosuccinate (USA) is an intermediate in uracil biosynthesis whose chance resemblance to allantoate makes it a substrate for uptake by Dal5p. Thus, ure2 mutants can take up ureidosuccinate (USA+) on ammonia-containing media whereas wild-type cells cannot. The wild-type Ure2p is found as a dimer

Although URE3 could be efficiently cured by growth of cells on medium containing 5•mM guanidine, from these cured cells could again be isolated strains that had acquired URE3 de novo (reversible curability); Overproduction of Ure2p increased the frequency with which URE3 arose by 100-fold. Ure2p is protease-resistant in URE3 strains, compared with normal strains. Moreover, URE3 arises de novo, and it is the Ure2 protein (not the mRNA or high copy gene) whose overproduction induces this event. The N-terminal 65•residues of Ure2p comprise the "prion domain" of the molecule, being sufficient when overproduced to induce de novo formation of URE3 and to propagate it and necessary in cis for a Ure2p molecule to be affected by the presence of URE3. Deletion of the prion domain leaves a C-terminal fragment capable of carrying out nitrogen regulation (the "nitrogen-regulation domain"). We show here that Ure2-GFP fusion proteins form intracellular aggregates specifically in URE3 strains. In the course of this work, we found that overexpression of such fusion proteins and certain fragments of Ure2p can cure the URE3 prion, suggesting a means to approach treatment of other prion diseases.

The aggregate's size distribution is unlike that expected if Ure2p were associated, specifically in URE3 strains, with an organelle such as the mitochondria, vacuole, nucleus, or endoplasmic reticulum, but we cannot completely rule out this type of explanation. The leading model for the mechanism of prion propagation is the "crystal seed" model, in which fragments of amyloid serve to prime the polymerization of the normal protein to make more amyloid. The energy of interaction of the normal form with the amyloid is used to drive the polymerization and a change in conformation of the protein. As with any crystal, the growth of the crystal of amyloid is poisoned by heterogeneity of the crystallizing molecules.

We have found that overexpression of Ure2p-GFP fusion proteins cure URE3, an indication of interference with the propagation mechanism. Fragments of Ure2p not including GFP also cure a URE3 based on full length Ure2p, but overproduction of full length Ure2p itself does not cure. It is striking that overexpression of the Ure2p prion domain fragment can both induce the de novo appearance of URE3 in a strain that was previously [ure-o] and can cure URE3 from a strain that began with the prion.

We suggest that, in the first case, the prion domain fragment can easily form a [an initial] crystal seed because it is not stabilized by the Ure2p C-terminal domain whereas, in the latter case, it interrupts the growth of the crystal formed of full length Ure2p. The "strain" of prion cured by the overproduced Ure2p1-65 was induced by overproduction of the full length Ure2p (20). It is possible that Ure2p1-65 induces a different prion strain and that they are, in some sense, incompatible. Overexpression of the C-terminal part of Ure2p also cures, perhaps by association with the C-termini of intact molecules.

The fact that overexpression of Hsp104 cures PSI suggests the possibility that cells may react to the sudden overproduction of Ure2p fusions or fragments by producing some chaperone or other molecule that reverses the prion change. Alternatively, the overproduced molecule may consume a limiting factor that is necessary for URE3 prion propagation.

Could this curing of URE3 by expressing fragments of the offending protein be applied to curing of other prion diseases or amyloid diseases in general? Peptides or other compounds that could fit in the crystal or filament growing points, but not provide a new growing point themselves, could poison amyloid propagation, just as fragments of Ure2p cure URE3.

Prion Domain Initiation of Amyloid Formation in Vitro from Native Ure2p.

Science 1999 Feb 26;283(5406):1339-1343 
Taylor KL, Cheng N, Williams RW, Steven AC, Wickner RB
The [URE3] non-Mendelian genetic element of Saccharomyces cerevisiae is an infectious protein (prion) form of Ure2p, a regulator of nitrogen catabolism. Here, synthetic Ure2p1-65 were shown to polymerize to form filaments 40 to 45 angstroms in diameter with more than 60 percent beta sheet. Ure2p1-65 specifically induced full-length native Ure2p to copolymerize under conditions where native Ure2p alone did not polymerize. Like Ure2p in extracts of [URE3] strains, these 180- to 220-angstrom-diameter filaments were protease resistant. The Ure2p1-65-Ure2p cofilaments could seed polymerization of native Ure2p to form thicker, less regular filaments. All filaments stained with Congo Red to produce the green birefringence typical of amyloid. This self-propagating amyloid formation can explain the properties of [URE3].

Amyloid is defined as a filamentous protein structure that stains with the dye Congo Red (CR) to produce green birefringence under polarized light and is characterized by protease resistance and an antiparallel •sheet structure (13: cite to GG Glenner 1980 review, also R. Kisilevsky and P. E. Fraser, Crit. Rev. Biochem. Mol. Biol. 32, 361 (1997)).

The 354-residue Ure2p is normally a dimer [unpublished]. Overexpression of the first 65•residues of Ure2p (the prion domain) induces de novo formation of the [URE3] prion at >1000-fold the spontaneous rate. Deletion of the first 65•residues leaves a COOH-terminal fragment (the nitrogen regulation domain) competent in nitrogen regulation but unaffected by the [URE3] prion. The prion domain can also propagate [URE3] in the absence of the nitrogen regulation domain. Thus, the NH2-terminal 65•residues are necessary for Ure2p to be altered to the prion form and sufficient to induce the change in normal Ure2p.

A report [by Wuthrich's group] of filament formation by the NH2-terminal domain 2-114 of Sup35p aged for 1 week at pH 2 also alludes [ie, observed -- webmaster] to filament formation by the Ure2p prion domain under these conditions, but these filaments were not described. Here, a copolymer filament apparently had a backbone of a prion domain protofilament surrounded by the remainder of Ure2p. The latter portion was digested by proteinase K, with accumulation of the resistant 7-•to 10-kD fragment.... Ure2p165-Ure2p and Ure2p165 filaments bound 14.8•and 3.0•CR molecules per monomer, with dissociation constant (Kd) values of 1.7 and 0.81•µM, respectively...Ure2p amyloid formation is a seeded process capable of continued propagation in vitro.

We suggest that the filament structure formed by Ure2p165 also forms the core of the equimolar cofilament with intact Ure2p and of the propagated fiber composed mainly of intact Ure2p, with the prion domain stacking in •sheets and the COOH-terminal domain protruding to form the wavy, thicker structure. [This is probably an alternating copolymer with the prion-like domain driving the cross-beta structure and exploiting its role in the natural dimer structure. There is possible relevence to heterozygous sporadic and familial CJD-- webmaster]

We suggest that, in [URE3] cells, amyloid filaments recruit most of the Ure2p in the cytoplasm. Ure2p in filaments is inactive or unable to enter the nucleus. Mating of [URE3] and [ure-o] cells transmits filaments to the cytoplasm of all progeny cells, which seed further filament formation. However, final proof that this is [URE3] requires characterization of Ure2p from [URE3] strains and transmission of [URE3] to yeast cells by amyloid filaments formed in vitro.

Characterization of the interaction domains of Ure2p, a prion-like protein of yeast.

Biochem J 1999 Mar 1;338(Pt 2):403-407
Fernandez-Bellot E, Guillemet E, Baudin-Baillieu A, Gaumer S, Komar AA, Cullin C
In the yeast Saccharomyces cerevisiae, the non-Mendelian inherited genetic element [URE3] behaves as a prion. A hypothesis has been put forward which states that [URE3] arises spontaneously from its cellular isoform Ure2p (the product of the URE2 gene), and propagates through interactions of the N-terminal domain of the protein, thus leading to its aggregation and loss of function. In the present study, various N- and C-terminal deletion mutants of Ure2p were constructed and their cross-interactions were tested in vitro and in vivo using affinity binding and a two-hybrid analysis. We show that the self-interaction of the protein is mediated by at least two domains, corresponding to the first third of the protein (the so-called prion-forming domain) and the C-terminal catalytic domain.

Comment (webmaster): Both yeast prion-like disorders involve loss-of-function through trapping of normal protein in fibrils. This does not seem to be the case in AD or CJD where the fibril itself seems to have toxic properties. A yeast cell of course divides long before any gradual toxicity could emerge.

Secondly, a glance at the prion-like regions shows immediately that these two proteins fit with Glenner's conformational disease scheme as glutamine (resp. asparagine for Ure2p) repeat disorders. In fact, the prion-like domains are easily predictable [indeed the webmaster did this a year or two back] and the two amyloid-inclined proteins themselves could have been found simply by analyzing the yeast proteome. This aspect of Ure2p is shown dramatically below -- the prion-like region probably extends to residue 7 (or 89 considering glutamines), not 65.

GenBank  1302253 Ure2p      
     1 MMNNNGNQVS NLSNALRQVN IGNRNSNTTT DQSNINFEFS 
    41 TGVNNNNNNN SSSNNNNVQN NNSGRNGSQN NDNENNIKNT 
    81 LEQHRQQQQA FSDMSHVEYS RITKFFQEQP LEGYTLFSHR 
   121 SAPNGFKVAI VLSELGFHYN TIFLDFNLGE HRAPEFVSVN 
   161 PNARVPALID HGMDNLSIWE SGAILLHLVN KYYKETGNPL 
   201 LWSDDLADQS QINAWLFFQT SGHAPMIGQA LHFRYFHSQK 
   241 IASAVERYTD EVRRVYGVVE MALAERREAL VMELDTENAA 
   281 AYSAGTTPMS QSRFFDYPVW LVGDKLTIAD LAFVPWNNVV 
   321 DRIGINIKIE FPEVYKWTKH MMRRPAVIKA LRGE
MMN
N
N
GN
QVSN
LSN
ALRQVN
IGN
RN
SN
TTTDQSN
IN
FEFSTGVN
N
N
N
N
N
N
SSSN
N
N
N
VQN
N
N
SGRN (residue 66)
GSQN
N
DN
EN
N
IKN (residue 79)
TLEQHRQQQQ (residue 89)
AFSDMSHVEYSRITKFFQEQPLEGYTLFSHRSAPN
GFKVAIVLSELGFHYN
TIFLDFN
LGEHRAPEFVSVN
PN
ARVPALIDHGMDN
LSIWESGAILLHLVN
KYYKETGN
PLLWSDDLADQSQIN
AWLFFQTSGHAPMIGQALHFRYFHSQKIASAVERYTDEVRRVYGVVEMALAERREALVMELDTEN
AAAYSAGTTPMSQSRFFDYPVWLVGDKLTIADLAFVPWN
N
VVDRIGIN
IKIEFPEVYKWTKHMMRRPAVIKALRGE

The yeast non-Mendelian factor [ETA+] is a variant of [PSI+], a prion-like form of release factor eRF3.

EMBO J 1999 Mar 1;18(5):1182-1191
Zhou P, Derkatch IL, Uptain SM, Patino MM, Lindquist S, Liebman SW
The yeast non-Mendelian factor [ETA+] is lethal in the presence of certain mutations in the SUP35 and SUP45 genes, which code for the translational release factors eRF3 and eRF1, respectively. One such mutation, sup35-2, is now shown to contain a UAG stop codon prior to the essential region of the gene. The non-Mendelian inheritance of [ETA+] is reminiscent of the yeast [PSI+] element, which is due to a self-propagating conformation of Sup35p. Here we show that [ETA+] and [PSI+] share many characteristics.

Indeed, like [PSI+], the maintenance of [ETA+] requires the N-terminal region of Sup35p and depends on an appropriate level of the chaperone protein Hsp104. Moreover, [ETA+] can be induced de novo by excess Sup35p, and [ETA+] cells have a weak nonsense suppressor phenotype characteristic of weak [PSI+]. We conclude that [ETA+] is actually a weak, unstable variant of [PSI+]. We find that although some Sup35p aggregates in [ETA+] cells, more Sup35p remains soluble in [ETA+] cells than in isogenic strong [PSI+] cells. Our data suggest that the amount of soluble Sup35p determines the strength of translational nonsense suppression associated with different [PSI+] variants.

The PNM2 mutation in the prion protein domain of SUP35 has distinct effects on different variants of the [PSI+] prion in yeast.

Curr Genet 1999 Mar 9;35(2):59-67 
Derkatch IL, Bradley ME, Zhou P, Liebman SW
We have previously described different variants of the yeast prion [PSI+] that can be obtained and maintained in the same genetic background. These [PSI+] variants, which differ in the efficiency of nonsense suppression, mitotic stability and the efficiency of curing by GuHCl, may correspond to different [PSI+] prion conformations of Sup35p or to different types of prion aggregates. Here we investigate the effects of overexpressing a mutant allele of SUP35 and find different effects on weak and strong [PSI+] variants: the suppressor phenotype of weak [PSI+] factors is increased, whereas the suppressor effect of strong [PSI+] factors is reduced.

The SUP35 mutation used was originally described as a "Psi no more" mutation (PNM2) because it caused loss of [PSI+]. However, none of the [PSI+] variants in the strains used in our study were cured by PNM2. Indeed, when overexpressed, PNM2 induced the de novo appearance of both weak and strong [PSI+] variants with approximately the same efficiency as the overexpressed wild-type SUP35 allele. Our data suggest that the change in the region of oligopeptide repeats in the Sup35p N-terminus due to the PNM2 mutation modifies, but does not impair, the function of the prion domain of Sup35p.

Cryo-electron microscopy structure of an SH3 amyloid fibril and model of the molecular packing

EMBO Journal Vol. 18,pp. 815-821 1999
Josª L. Jimªnez1.. and Helen Saibil
   
Amyloid fibrils are assemblies of misfolded proteins and are associated with pathological conditions such as Alzheimer's disease and the spongiform encephalopathies. In the amyloid diseases, a diverse group of normally soluble proteins self-assemble to form insoluble•fibrils. X-ray fibre diffraction studies have shown that the protofilament cores of fibrils formed from the various proteins all contain a cross-beta-scaffold, with beta-strands perpendicular and beta-sheets parallel to•the fibre axis. We have determined the threedimensional structure of an amyloid fibril, formed by the SH3 domain of phosphatidylinositol-3'-kinase, using cryo-electron microscopy and image processing at 25•’•resolution.

The structure is a double helix of two protofilament pairs wound around a hollow core, with a helical crossover repeat of ~600 ’•and an axial subunit repeat of ~27 ’. The native SH3 domain is too compact to fit into the fibril density, and must unfold to adopt a longer, thinner shape in the amyloid form. The 20x40-’ protofilaments can only accommodate one pair of flat beta-sheets stacked against each other, with very little inter-strand twist. We propose a model for the polypeptide packing as a basis for understanding the structure of amyloid fibrils in general.

14-3-3 protein, neuron-specific enolase, and S-100 protein in cerebrospinal fluid of patients with Creutzfeldt-Jakob disease.

Dement Geriatr Cogn Disord 1999 Jan-Feb;10(1):40-6 
Beaudry P, Cohen P, Brandel JP, Delasnerie-Laupretre N, Richard S, Launay JM, Laplanche JL
We explored simultaneously 14-3-3 protein, neuron-specific enolase (NSE), and one astroglial protein, S-100, recently proposed as Creutzfeld-Jakob disease (CJD) markers, in the cerebrospinal fluid (CSF) of 129 patients with suspected CJD. Cutoff values for NSE and S-100 were established at 25 and 2.5 ng/ml, respectively. The highest sensitivity was observed for S-100 (94.2%) followed by 14-3-3 (89.8%) and NSE (79.7%), while the highest specificity in CJD diagnosis was obtained with 14-3-3 protein (100%) as compared with NSE (91.5%) and S-100 (85.4%). No influence of sex, genotype at codon 129 of the prion protein gene, time between sampling, and death or disease duration has been found.

Based on 90 cases initially referred as 'probable' or 'possible' CJD, with 14-3-3, NSE, or S-100 we could correctly discriminate between 'CJD' or 'non-CJD' categories in 94.4, 86.5, and 90% of the cases, respectively. When limited to 'possible CJD' cases, diagnosis based on one of the three CSF proteins was accurate in 98, 90.7 and 87.3%, respectively. In view of the fact that the CSF 14-3-3 protein test alone has the highest specificity and good sensitivity, it appears that there is no additional advantage at the moment to include NSE and/or S-100 protein in the exploration of clinically suspected CJD cases.

Subtypes of S100 proteins must be identified

British Medical Journal, 318:538  February 20, 1999  C W Heizmann
It is absolutely necessary to determine which S100 protein is measured in studies, such as that by Otto et al,1 that use these proteins to diagnose Creutzfeldt-Jakob disease. Eighteen S100 proteins are now known, and they have a divergent pattern of cell specific and tissue specific expression, distinct subcellular localisations, different affinities for Ca++ but also for Zn++ and Cu++, and distinct intracellular and extracellular functions.

Several S100 proteins are abundant in the brain . S100B and S100A6, for example, are expressed there in different subpopulations of neurones and glial cells.4 Therefore, the subtype of S100 protein must be identified if the diagnosis of Creutzfeldt-Jakob disease is to be valid. Furthermore, commercially available antibodies used in most studies are directed against a mixture of bovine brain S100 proteins; depending on the manufacturer, these react mostly against S100B but also against other S100 proteins.5 The studies by Otto et al probably determined concentrations of S100B. S100B, however, is closely associated with Alzheimer's disease. In addition, blood concentrations of S100B are of prognostic value for malignant melanoma and are a measure for brain damage after cardiac arrest.

All these complications could be circumvented by developing more specific and sensitive tests for measuring the individual brain S100 proteins in neurodegenerative disorders. Several well defined antibodies to S100 are now available.

Scrapie-infected mice and PrP knockout mice share abnormal localization and activity of neuronal nitric oxide synthase.

J Neurochem 1999 Mar;72(3):1224-31
Keshet GI, Ovadia H, Taraboulos A, Gabizon R
..The physiological role of PrPc, a glycolipid-anchored glycoprotein, is still unknown. We have shown previously that neuronal nitric oxide synthase (nNOS) activity is impaired in the brains of mice sick with experimental scrapie as well as in scrapie-infected neuroblastoma cells. In this work we investigated the cell localization of nNOS in brains of wild-type and scrapie-infected mice as well as in mice in which the PrP gene was ablated.

We now report that whereas in wild-type mice, nNOS, like PrPc, is associated with detergent-insoluble cholesterol-rich membranous microdomains (rafts), this is not the case in brains of scrapie-infected or in those of adult PrP(0/0) mice. Also, adult PrP(0/0), like scrapie-infected mice, show reduced nNOS activity. We suggest that PrPc may play a role in the targeting of nNOS to its proper subcellular localization. The similarities of nNOS properties in PrP(0/0) as compared with scrapie-infected mice suggest that at least this role of PrPc may be impaired in scrapie-infected brains.

Comment (webmaster): This is an interesting result. A relationship with nitric oxide was suggested here earlier on the basis of structural studies. The modified arginine of the prion protein could conceivably be the anchor to nNOS, given that arginine is the latter enzyme's substrate.

Fatal familial insomnia: a new Austrian family.

Brain 1999 Jan;122 (Pt 1):5-16 
Almer G, Hainfellner JA, Brucke T, Jellinger K, Kleinert R, Bayer G, Windl O,
Kretzschmar HA, Hill A, Sidle K, Collinge J, Budka H
We present clinical, pathological and molecular features of the first Austrian family with fatal familial insomnia. Detailed clinical data are available in five patients and autopsy in four patients. Age at onset of disease ranged between 20 and 60 years, and disease duration between 8 and 20 months. Severe loss of weight was an early symptom in all five patients. Four patients developed insomnia and/or autonomic dysfunction, and all five patients developed motor abnormalities. Analysis of the prion protein (PrP) gene revealed the codon 178 point mutation D178N and methionine homozygosity at position 129.

In all brains, neuropathology showed widespread cortical astrogliosis, widespread brainstem nuclei and tract degeneration, and olivary 'pseudohypertrophy' with vacuolated neurons, in addition to neuropathological features described previously, such as thalamic and olivary degeneration. Western blotting of one brain and immunocytochemistry in four brains revealed quantitative and regional dissociation between PrP(res)(the protease resistant form of PrP) deposition and histopathology. In the cerebellar cortex of one patient, PrP(res) deposits were prominent in the molecular layer and displayed a peculiar patchy and strip-like pattern with perpendicular orientation to the surface. In another patient, a single vacuolated neuron in the inferior olivary nuclei contained prominent intravacuolar granular PrP(res) deposits, resembling changes of brainstem neurons in bovine spongiform encephalopathy.

Characterization of high affinity binding between laminin and the acute-phase protein, serum amyloid A.

Ancsin JB, Kisilevsky R
J Biol Chem 1997 Jan 3;272(1):406-13 
Serum amyloid A isoforms, apoSAA1 and apoSAA2, are acute-phase proteins of unknown function and can be precursors of amyloid AA peptides (AA) found in animal and human amyloid deposits. These deposits are often a complication of chronic inflammatory disorders and are associated with a local disturbance in basement membrane (BM). In the course of trying to understand the pathogenesis of this disease laminin, a major BM glycoprotein, has been discovered to bind saturably, and with high affinity to murine acute-phase apoSAA. This interaction involves a single class of binding sites, which are ionic in nature, conformation-dependent, and possibly involve sulfhydryls. Binding activity was significantly enhanced by Zn2+, an effect possibly mediated through Cys-rich zinc finger-like sequences on laminin. ...

Since laminin binds apoSAA with high affinity and has previously been shown to codeposit with AA amyloid fibrils, we postulate that laminin interacts with apoSAA and facilitates nucleation events leading to fibrillogenesis. This work also provides further support for the hypothesis that a disturbance in BM metabolism contributes to the genesis of amyloid. The specificity and avidity of the laminin-apoSAA interaction also implies that it may be a normal event occurring during the inflammatory process, which mediates one or more of the functions recently proposed for apoSAA.

[Recall prion protein binds the laminin receptor precursor at the same site that laminin does. -- webmaster]

A novel epitope for the specific detection of exogenous prion proteins

Virology 1999 Mar 1;255(1):26-31 
Vorberg I, Buschmann A, Harmeyer S, Saalm ller A, Pfaff E, Groschup MH
...PrP conversion experiments in scrapie infected tissue culture cells, transgenic mice, and cell-free systems usually require unique epitopes and corresponding monoclonal antibodies (MAbs) for the immunological discrimination of exogenously introduced and endogenous PrP compounds (e.g., MAb 3F4, which is directed to an epitope on hamster and human but not on murine PrP).

The novel MAb designated L42 reacts to PrP of a variety of species, including cattle, sheep, goat, dog, human, cat, mink, rabbit, and guinea pig [still not sequenced -- webmaster], but does not bind to mouse, hamster, and rat PrP. Therefore, MAb L42 may allow future in vitro conversion and transgenic studies on PrPs of the former species. The MAb L42 epitope on PrPC includes a tyrosine residue at position 144, whereas mouse, rat, and hamster PrPs incorporate tryptophane at this site.

We generated PrP expression vectors coding for authentic or mutated murine PrPCs (i.e., codon 144 encoding tyrosine instead of tryptophan). After transfection into neuroblastoma cells, MAb L42 did not react with immunoblotted wild-type murine PrPC, whereas L42 epitope-tagged murine PrPC was strongly recognized. Immunoblot and fluorescence-activated cell sorting data revealed that tagged PrPC was correctly posttranslationally processed and translocated to the cell surface.

Risk of nvCJD in Blood: DNV assessment

Feb 26, 1999  Philip Comer De Norkse Veritas consultant
The risk assessment study that DNV were asked to do by the UK Dept of Health has now been made public (see recent press release from DOH on www.doh.gov.uk that also deals with the SEACV decision on pentosan). The full report is available on the DNV web site. An overview of the report below.

Assessment of Risk from new variant CJD in Blood and Blood Products

The epidemic of BSE in the cattle herd of the United Kingdom is now well under control, with the numbers of new cases reducing significantly every year. The situation for the new variant Creutzfeldt Jacob Disease (nvCJD), which is believed to result from exposure to BSE infectivity in meat products, is less clear. There have so far been a total of 35 cases, but experts are still not able to put any realistic upper bound on the total number of cases that could occur. Estimates compatible with the present number of cases and our current knowledge, range from under a hundred to several million.

One of the concerns about nvCJD is that if a large number of people have been exposed to the BSE agent in food, and so may be incubating nvCJD, then they may be able to pass on that infection through blood donations. As a result, the Spongiform Encephalopathy Advisory Committee (SEAC), who are the advisors on these issues to the UK government, advised that risk assessments be carried out to inform decisions on any measures that may be necessary to protect recipients of blood and blood products from the transmissible agent of nvCJD.

In January 1998, DNV'S London office were awarded a contract by the UK Department of Health to carry out the risk assessment study, and the Final Report "Assessment of the Risk of Exposure to nvCJD Infectivity in Blood and Blood Products", was published on the 18th February 1999.

The study reviewed the available evidence for infectivity in blood, and concluded that blood from people with nvCJD may contain infectivity that could be transmitted through blood transfusions, although this has not been proved conclusively.

The study has considered the way in which blood is collected and processed, how the various blood components (red cells, fresh frozen plasma and platelets) are used for patient treatments and the exposure of patients to plasma derivatives such as Factor VIII, Immunoglobulin (IgG) and albumin. Estimates of infectivity in each of the main blood components and in plasma fractions have been derived from the data from some animal experiments, and the range of possible values identified. These are used to estimate infectivity in standard doses of a range of plasma products such as Factor VIII, albumin, IgG, etc. The exposure of a defined set of representative patient groups to nvCJD infectivity has then been assessed to estimate the number of new infections and the number of nvCJD cases that could result. The results have been presented in terms of the numbers of infections or cases per infected donation.

The sensitivity of the results to variations in the main assumptions has been assessed and the effectiveness of a number of risk-reducing measures evaluated, for example, leucodepletion, elimination of UK sourced plasma, prevention of transfusion recipients from giving blood and prophylactic treatment using pentosan polysulphate.

DNV consulted widely in the preparation of the report, and the report was sent out by the Department of Health for peer review by a panel of international experts prior to being finalised for publication.

TSE regulation in Germany a muddle

[No title available]. [Article in German] 
DTW Dtsch Tierarztl Wochenschr 1998 Dec;105(12):475-81 
Fertig H
The decisive European legal provisions to fight bovine sponfiform encephalopathy in the context of the rendering and meat-hygiene legislation are the Commission Decisions 96/449/EC "on the approval of alternative heat treatment systems for processing animal waste with a view to the inactivation of spongiform encephalopathy agents" and 97/534/EC "on the prohibition of the use of material presenting risks as regards transmissible spongiform encephalopathies". Both decisions are based on Council Directives which do not provide the necessary authorization for these decisions by the Commission. Consequently, both have to be regarded as legally invalid. Furthermore, the legal acts to convert these decisions into German law (Rendering Plants Regulation and Meat-Hygiene Regulation) have to be considered invalid--partly due to formal and partly due to factual reasons. Because of the thus created legal uncertainty the legal provisions in question can only come fully into force after the elimination of this specifically described legal shortcomings or after clarification of the legal situation by the responsible court

Scientists fight for right to withhold data

Colin•macilwain 11 February 1999 Nature 397, 459
A law forcing scientists to hand over raw data under the Freedom of Information Act (FOIA) could be weakened by new proposals from the White House. But the plan by the White House Office of Management and Budget (OMB) to interpret the law narrowly has done little to dampen resistance from universities and scientific societies, who want it revoked. They acknowledge the OMB move as an effort to take researchers' concerns into account. But they still fear the law would expose researchers to harassment from people who wish to interfere with their work, while making it difficult to protect confidential data related to medical studies or intellectual property claims.

The proposed rule, published on 4 February, explains how the OMB will implement a piece of legislation added to last October's Omnibus Appropriations bill by Senator Richard Shelby (Republican, Alabama). Shelby's law, incorporated at the last minute, requires non-government scientists on federal grants to hand over all raw data to third parties who request it under the FOIA.

The OMB rule, on the other hand, would only require raw data to be made available when the final research findings had already been published, and only if that research had been "used by the federal government in developing policy or rules". Comments are invited until 5 April, after which the OMB will issue a binding rule.

A 1980 Supreme Court ruling confirmed that university researchers and other people on grants are not subject to FOIA requests, which are mainly used as a means to obtain government documents. Scientists fear that the new law will expose researchers in controversial areas -- such as global warming or the epidemiological study of the effects of pollutants -- to demands from interest groups who want to see all their notebooks, papers and computer records.

Shelby had quietly inserted his legislation into the 4,000-page omnibus appropriations bill in response to a case in 1997, when industrial groups failed to persuade Harvard University to hand over the raw data behind a piece of published research cited by the Environmental Protection Agency in support of tightening regulations on fuel emissions. The study included medical details provided on condition of anonymity: researchers said that, even with names taken out, people could still be identified. A few other scientists have been allowed to use the data. But industry groups such as the American Petroleum Institute say that the data should be available for review by any qualified investigators with "a legitimate scientific interest".

"A researcher's notebooks are full of raw material, just like an FBI file, not all of which is of equal standing," says David Korn, senior vice-president for research at the American Association of Medical Colleges. "To require all of that to be made publicly available is just bad science policy."

Korn describes the proposed White House rule as "a very valiant effort" to implement the law in a manner that is acceptable to the research community. But he adds: "I think the problem is that the basic statute is bad, and a lot of people believe that you can never make a bad law good." It is "very probable" that the association of medical colleges would now back legislation to repeal the Shelby legislation, he says. "We still think this is very troubling."

"We believe that OMB has made a good-faith effort, and has demonstrated sensitivity to our community's concerns," said Nils Hasselmo, president of the Association of American Universities, which represents the leading US research universities. "We are consulting with our campuses and other scientific societies to provide extensive comments to OMB."

George Brown (California), the senior Democrat on the House Science Committee, has already proposed such legislation. But, says Korn: "Republican members are going to have to get on to this if it is going to go anywhere." Republican supporters of science such as John Porter (Illinois) have joined Brown in expressing their concern on the issue. But it will be awkward for them to propose the immediate repeal of a provision which was added to the appropriations bill by leading senators of their own party.

Shelby's office said that he had not yet reviewed the proposed rule. Lawyers at the National Institutes of Health (NIH), meanwhile, have warned scientists that they will have to pay themselves for extra administrative work they do to satisfy demands made under the new law. NIH won't be able to pay for such work, they say, and even if NIH obtains a fee from the organization asking for the data, the money will go straight to the US Treasury.

Ill-advised 'freedom' of scientific information

11 February 1999  Nature 397, 455 (1999) © Macmillan Publishers Ltd. 
The sharing of data by researchers ought to be encouraged. But a compulsion to release raw data and notes in current US openness laws is the wrong way to achieve it, as is a proposed amendment.

The principle of granting maximum public access to government records, as embodied in the Freedom of Information Act (FOIA), is a sound one which has strengthened democracy in the United States, and from which secretive regimes elsewhere in the world have much to learn. However, a new law, passed last October, that would shed similar light on scientific records, threatens to undermine academic research, while contributing nothing to open government.

Like so many of Washington's finest ruses, the new legislation was passed in the dead of night, without hearings or outside consultation. Senator Richard Shelby (Republican, Alabama) had it quietly inserted into last October's unwieldy, 4,000-page omnibus spending act, as a prerequisite for the funding of the White House's small but powerful Office of Management and Budget (OMB). The sponsors of the measure were apparently concerned at the time about the unwillingness of researchers at the Harvard School of Public Health to release raw data behind an epidemiological study of the health effects of small carbon particles ('particulates'), which was used by the Environmental Protection Agency as a basis for regulation.

The act itself says that OMB should amend an existing circular to ensure that "all data" produced under a federal research grant be made available to the public through the procedures established under FOIA. That set off alarm bells in the scientific community, which feared that FOIA requests might be used to obtain scientific data even before publication of research findings -- opening the door to the merciless harassment of scientists by hostile third parties.

Last week the OMB issued a draft amendment that would make data accessible under FOIA only after research findings had been published and used by the government "in developing policy or rules" (see page 459). The OMB proposal still casts a wide net, however. A great deal of scientific research is arguably used by the government in that way. The sequestration and re-interpretation of a scientist's notes and computer records after publication may prove to be only marginally less disruptive than it would have been beforehand. Some scientists will avoid controversial fields of endeavour, such as pollution-related research, if the controversy is accompanied by the threat of inquisitions into their records and methods by well-financed special interest groups. Patients and commercial partners may doubt that the exemptions allowed by FOIA will protect their privacy.

The proposed change would also pull the academic research enterprise more closely under the wing of the federal government. The US Supreme Court has properly resisted the notion that academics on federal grants are agents of government, or that they be subject to the bureaucracy which enables government departments to comply with laws such as FOIA. Such subservience to government would quickly stifle the freedom on which the United States has built its scientific strength. That factor seems to have been ignored by Shelby and Trent Lott (Republican, Mississippi), the leader of the Senate, in their rush to legislate.

Universities and scientific societies are hoping that by 5 April, when its public consultation period ends, OMB will receive a loud and clear message from the scientific community about its proposed rule. That message should be that the law needs to be repealed, while acknowledging a need for an enhanced availability of primary data. The development of mechanisms to achieve that, with the full involvement of the scientific community, holds far more promise than the draconian measure which has unfortunately been passed into law.

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