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Markus Glatzel

Publications and source records attributed to Markus Glatzel.

At least 19 recordsLinked to original sources

Human transmissible spongiform encephalopathies in eleven countries: diagnostic pattern across time, 1993-2002.

BACKGROUND: The objective of this study was to describe the diagnostic panorama of human transmissible spongiform encephalopathies across 11 countries. METHODS: From data collected for surveillance purposes, we describe annual proportions of deaths due to different human transmissible spongiform encephalopathies in eleven EUROCJD-consortium countries over the period 1993-2002, as well as variations in the use of diagnostic tests. Using logistic models we quantified international differences and changes across time. RESULTS: In general, pre-mortem use of diagnostic investigations increased with time. International differences in pathological confirmation of sporadic Creutzfeldt-Jakob disease, stable over time, were evident. Compared to their counterparts, some countries displayed remarkable patterns, such as: 1) the high proportion, increasing with time, of variant Creutzfeldt-Jakob disease in the United Kingdom, (OR 607.99 95% CI 84.72-4363.40), and France (OR 18.35, 95% CI 2.20-152.83); 2) high, decreasing proportions of iatrogenic Creutzfeldt-Jakob disease in France, (OR 5.81 95% CI 4.09-8.24), and the United Kingdom, (OR 1.54 95% CI 1.03-2.30); and, 3) high and stable ratios of genetic forms in Slovakia (OR 21.82 95% CI 12.42-38.33) and Italy (OR 2.12 95% CI 1.69-2.68). CONCLUSION: Considerable international variation in aetiological subtypes of human transmissible spongiform encephalopathies was evident over the observation period. With the exception of variant Creutzfeldt-Jakob disease and iatrogenic Creutzfeldt-Jakob disease in France and the United Kingdom, these differences persisted across time.

Australia↗

Strain fidelity of chronic wasting disease upon murine adaptation.

Chronic wasting disease (CWD), a prion disease of deer and elk, is highly prevalent in some regions of North America. The establishment of mouse-adapted CWD prions has proven difficult due to the strong species barrier between mice and deer. Here we report the efficient transmission of CWD to transgenic mice overexpressing murine PrP. All mice developed disease 500 +/- 62 days after intracerebral CWD challenge. The incubation period decreased to 228 +/- 103 days on secondary passage and to 162 +/- 6 days on tertiary passage. Mice developed very large, radially structured cerebral amyloid plaques similar to those of CWD-infected deer and elk. PrP(Sc) was detected in spleen, indicating that murine CWD was lymphotropic. PrP(Sc) glycoform profiles maintained a predominantly diglycosylated PrP pattern, as seen with CWD in deer and elk, across all passages. Therefore, all pathological, biochemical, and histological strain characteristics of CWD appear to persist upon repetitive serial passage through mice. These findings indicate that the salient strain-specific properties of CWD are encoded by agent-intrinsic components rather than by host factors.

Amino Acid Sequence↗

The LPS receptor, CD14, in experimental autoimmune encephalomyelitis and multiple sclerosis.

Innate immune receptors are crucial for defense against microorganisms. Recently, a cross-talk between innate and adaptive immunity has been considered. Here, we provide first evidence for a role of the key innate immune receptor, LPS receptor (CD14) in pathophysiology of experimental autoimmune encephalomyelitis, the animal model of multiple sclerosis. Indicating a functional importance in vivo, we show that CD14 deficiency increased clinical symptoms in active experimental autoimmune encephalomyelitis. Consistent with these observations, CD14 deficient mice exhibited a markedly enhanced infiltration of monocytes and neutrophils in brain and spinal cord. Moreover, we observed an increased immunoreactivity of CD14 in biopsy and post mortem brain tissues of multiple sclerosis patients compared to age-matched controls. Thus, the key innate immune receptor, CD14, may be of pathophysiological relevance in experimental autoimmune encephalomyelitis and multiple sclerosis.

Animals↗

Cerebrovascular P-glycoprotein expression is decreased in Creutzfeldt-Jakob disease.

The abnormal conformation and assembly of proteins in the central nervous system is increasingly thought to be a critical pathogenic mechanism in neurodegenerative disorders such as Creutzfeldt-Jakob disease (CJD) and Alzheimer's disease (AD). CJD is marked primarily by the buildup of misfolded prion protein (PrP(Sc)) in brain, whereas the accrual of beta-amyloid protein (Abeta) and tau protein are characteristic for AD. Prior studies have shown that the ATP-binding cassette transporter P-glycoprotein (P-gp) is a cellular efflux pump for Abeta, and that age-associated deficits in P-gp may be involved in the pathogenesis of Alzheimer's disease. In the present study, we investigated the relationship between P-gp and idiopathic CJD, and found that CJD, like AD, is associated with a decrease in the expression of cerebrovascular P-gp. In some instances, Abeta and PrP deposits coexist in cases of CJD, suggesting the possibility of pathogenic interactions. Since there is, to date, no evidence that PrP itself is a substrate for P-gp, we hypothesize that the age-related deficits in P-gp could promote the accumulation of PrP(Sc) either by promoting the buildup of Abeta (which could act as a seed for the aggregation of PrP(Sc)), or by overloading the ubiquitin-proteasomal catabolic system, and thereby facilitating the accumulation of PrP. Alternatively, the loss of P-gp could be a non-specific response to neurodegenerative changes in the central nervous system. In either case, dysfunction of this critical toxin-elimination pathway in CJD and AD suggests that selectively increasing cerebrovascular P-gp function could open new therapeutic pathways for the prevention and/or treatment of a number of proteopathic disorders of the central nervous system.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Prion infections, blood and transfusions.

Prion infections lead to invariably fatal diseases of the CNS, including Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE), and scrapie in sheep. There have been hundreds of instances in which prions have been transmitted iatrogenically among humans, usually through neurosurgical procedures or administration of pituitary tissue extracts. Prions have not generally been regarded as blood-borne infectious agents, and case-control studies have failed to identify CJD in transfusion recipients. Previous understanding was, however, questioned by reports of prion infections in three recipients of blood donated by individuals who subsequently developed variant CJD. On reflection, hematogenic prion transmission does not come as a surprise, as involvement of extracerebral compartments such as lymphoid organs and skeletal muscle is common in most prion infections, and prions have been recovered from the blood of rodents and sheep. Novel diagnostic strategies, which might include the use of surrogate markers of prion infection, along with prion removal strategies, might help to control the risk of iatrogenic prion spread through blood transfusions.

Animals↗

Analysis of prion strains by PrPSc profiling in sporadic Creutzfeldt-Jakob disease.

BACKGROUND: Prion diseases are a group of invariably fatal neurodegenerative disorders affecting humans and a wide range of mammals. An essential part of the infectious agent, termed the prion, is composed of an abnormal isoform (PrPSc) of a host-encoded normal cellular protein (PrPC). The conversion of PrPC to PrPSc is thought to play a crucial role in the development of prion diseases and leads to PrPSc deposition, mainly in the central nervous system. Sporadic Creutzfeldt-Jakob disease (sCJD), the most common form of human prion disease, presents with a marked clinical heterogeneity. This diversity is accompanied by a molecular signature which can be defined by histological, biochemical, and genetic means. The molecular classification of sCJD is an important tool to aid in the understanding of underlying disease mechanisms and the development of therapy protocols. Comparability of classifications is hampered by disparity of applied methods and inter-observer variability. METHODS AND FINDINGS: To overcome these difficulties, we developed a new quantification protocol for PrPSc by using internal standards on each Western blot, which allows for generation and direct comparison of individual PrPSc profiles. By studying PrPSc profiles and PrPSc type expression within nine defined central nervous system areas of 50 patients with sCJD, we were able to show distinct PrPSc distribution patterns in diverse subtypes of sCJD. Furthermore, we were able to demonstrate the co-existence of more than one PrPSc type in individuals with sCJD in about 20% of all patients and in more than 50% of patients heterozygous for a polymorphism on codon 129 of the gene encoding the prion protein (PRNP). CONCLUSION: PrPSc profiling represents a valuable tool for the molecular classification of human prion diseases and has important implications for their diagnosis by brain biopsy. Our results show that the co-existence of more than one PrPSc type might be influenced by genetic and brain region-specific determinants. These findings provide valuable insights into the generation of distinct PrPSc types.

Aged↗

Genetic prion disease: the EUROCJD experience.

A total of 10-15% of human transmissible spongiform encephalopathies (TSEs) or prion diseases are characterised by disease-specific mutations in the prion protein gene (PRNP). We examined the phenotype, distribution, and frequency of genetic TSEs (gTSEs) in different countries/geographical regions. We collected standardised data on gTSEs between 1993 and 2002 in the framework of the EUROCJD collaborative surveillance project. Our results show that clinicopathological phenotypes include genetic Creutzfeldt-Jakob disease (gCJD), fatal familial insomnia (FFI), and Gerstmann-Sträussler-Scheinker disease (GSS). Genetic TSE patients with insert mutation in the PRNP represent a separate group. Point and insertional mutations in the PRNP gene varies significantly in frequency between countries. The commonest mutation is E200K. Absence of a positive family history is noted in a significant proportion of cases in all mutation types (12-88%). FFI and GSS patients develop disease earlier than gCJD. Base pair insertions associated with the Creutzfeldt-Jakob disease (CJD) phenotype, GSS, and FFI cases have a longer duration of illness compared to cases with point mutations and gCJD. Cerebrospinal fluid 14-3-3 immunoassay, EEG, and MRI brain scan are useful in the diagnosis of CJD with point mutations, but are less sensitive in the other forms. Given the low prevalence of family history, the term "gTSE" is preferable to "familial TSE". Application of genetic screening in clinical practice has the advantage of early diagnosis and may lead to the identification of a risk of a TSE.

Adult↗

Progressive scoliosis in central core disease.

Central core disease (CCD) is a rare congenital myopathy with autosomal dominant inheritance. Here, we report on two cases of progressive scoliosis in CCD, pointing out the value of a muscle biopsy to establish the correct diagnosis. The first case involves a 13-year-old boy with severe progressive scoliosis and joint contractures. The patient was initially diagnosed with arthropgryposis multiplex congenita. The second case involves a 45-year-old man with severe scoliosis that had slowly progressed over the years. Both patients suffered from unexplained muscle weakness and severe restriction of pulmonary function. The correct diagnoses were established through muscle biopsies taken from the paravertebral musculature during scoliosis surgery. Correction of the spinal deformities was achieved through posterior instrumentation in both patients, with prior anterior release in one patient. Although scoliosis is a common feature in CCD, the correct diagnosis can be missed in scoliosis patients. Therefore, we recommend a muscle biopsy in patients with scoliosis, unexplained muscle weakness and multiple joint problems.

Adolescent↗

Sporadic Creutzfeldt-Jakob disease: a comparison of pathological findings and diffusion weighted imaging.

To investigate a possible relationship between the severity of pathological and radiological lesions in diffusion-weighted MRI (DWI) we compared DWI findings from 6 sequential brain MRI scans with pathological features of numerous tissue blocks of different cortical and subcortical regions in a case of autopsy-proven sporadic CJD. Whereas DWI and pathological examination revealed multifocal, cortical and deep hyperintensities at corresponding localizations, no correlation between the degree of severity of radiologically visible and pathological damage was found. The characteristic focal involvement and extension of lesions of the cortex and the basal ganglia bilaterally shown by DWI may be an argument for the spreading of the disease per contiguitatem.

Cell Death↗

Human prion diseases: molecular and clinical aspects.

Compared with that of other human pathogens, the proposed replicative cycle of prions is disarmingly simple. It encompasses misfolding of a single protein, the cellular prion protein (PrPC), into a disease-associated form called PrPSc. This is followed by PrPSc aggregation and possibly fragmentation of aggregates, which may augment the number of replicative units. Although there is no formal proof of the correctness of this model, a wealth of evidence indicates that pathogen-encoded informational nucleic acids are dispensable for prion replication. Despite the simplicity of the replicative process, the human phenotypic range of prion diseases is extremely variable and includes the sporadic, inherited, and acquired forms of Creutzfeldt-Jakob disease. In addition, prion diseases occur in a wide range of animals and can be propagated within and between animal species. The present review article discusses current concepts and controversies surrounding the basic biological features of prions.

Animals↗

Coexistence of multiple PrPSc types in individuals with Creutzfeldt-Jakob disease.

BACKGROUND: The molecular typing of sporadic Creutzfeldt-Jakob disease (CJD) is based on the size and glycoform ratio of protease-resistant prion protein (PrP(Sc)), and on PRNP haplotype. On digestion with proteinase K, type 1 and type 2 PrP(Sc) display unglycosylated core fragments of 21 kDa and 19 kDa, resulting from cleavage around amino acids 82 and 97, respectively. METHODS: We generated anti-PrP monoclonal antibodies to epitopes immediately preceding the differential proteinase K cleavage sites. These antibodies, which were designated POM2 and POM12, recognise type 1, but not type 2, PrP(Sc). FINDINGS: We studied 114 brain samples from 70 patients with sporadic CJD and three patients with variant CJD. Every patient classified as CJD type 2, and all variant CJD patients, showed POM2/POM12 reactivity in the cerebellum and other PrP(Sc)-rich brain areas, with a typical PrP(Sc) type 1 migration pattern. INTERPRETATION: The regular coexistence of multiple PrP(Sc) types in patients with CJD casts doubts on the validity of electrophoretic PrP(Sc) mobilities as surrogates for prion strains, and questions the rational basis of current CJD classifications.

Antibodies, Monoclonal↗

No influence of amyloid-beta-degrading neprilysin activity on prion pathogenesis.

Transmissible spongiform encephalopathies are characterized by the accumulation of PrPSc, a protease-resistant form of a host-derived protein termed PrPC. Substantial evidence indicates that PrPSc represents an essential component of the infectious agent, which is termed prion. The accumulation of PrPSc within the central nervous system of prion-infected organisms is a dynamic process that is regulated both by production and by clearance of PrPSc. Although several proteases have been implicated in proteolysis of PrPC, the mechanisms underlying proteolysis of PrPSc remain unclear. Here, it was investigated whether neprilysin, a metalloprotease known to degrade extracellular amyloidogenic proteins such as amyloid-beta, plays a role in prion pathogenesis in vivo. As neprilysin has a broad substrate specificity and is localized subcellularly in the vicinity of PrP, it represents a plausible candidate for prion degradation. Prions were therefore administered to mice lacking or overexpressing neprilysin in brain. However, the gene dosage of neprilysin did not modulate accumulation of PrPSc in brain. Also, incubation times and clinical course of prion disease, as well as brain infectivity titres at terminal stage, were unaffected. These data rule out neprilysin as a major modulator of PrPSc accumulation and prion pathogenesis.

Amyloid beta-Peptides↗

Intrinsic resistance of oligodendrocytes to prion infection.

Within the CNS, the normal form of cellular prion protein (PrP(C)) is expressed on neurons, oligodendrocytes, and astrocytes. The contribution of these cell types to prion replication and pathogenesis is unclear. To assess the role of oligodendrocytes, we expressed PrP(C) under the control of the myelin basic protein (MBP) promoter in mice lacking endogenous PrP(C). PrP(C) was detected in oligodendrocytes and Schwann cells but not in neurons and astrocytes. MBP-PrP mice never developed scrapie after intracerebral, intraperitoneal, or intraocular challenge with scrapie prions. Transgenic brains did not contain protease-resistant prion protein and did not transmit scrapie when inoculated into PrP(C)-overexpressing indicator mice. To investigate whether prion spread within the CNS depends on oligodendrocytic PrP(C), we implanted PrP(C)-overexpressing neuroectodermal grafts into MBP-PrP brains. After intraocular prion inoculation, none of the grafts showed spongiform encephalopathy or prion infectivity. Hence oligodendrocytes do not support cell-autonomous prion replication, establishment of subclinical disease, and neural spread of prions. Prion resistance sets oligodendrocytes aside from both neurons and astrocytes.

Animals↗

Creutzfeldt-Jakob disease and inclusion body myositis: abundant disease-associated prion protein in muscle.

Pathologicalprion protein (PrP(Sc)) is the hallmark of prion diseases affecting primarily the central nervous system. Using immunohistochemistry, paraffin-embedded tissue blot, and Western blot, we demonstrated abundant PrP(Sc) in the muscle of a patient with sporadic Creutzfeldt-Jakob disease and inclusion body myositis. Extraneural PrP(C)-PrP(Sc) conversion in Creutzfeldt-Jakob disease appears to become prominent when PrP(C) is abundantly available as substrate, as in inclusion body myositis muscle.

Aged↗

Serial EEG findings in sporadic and iatrogenic Creutzfeldt-Jakob disease.

OBJECTIVE: To study temporal and spatial development of EEG patterns in sporadic and iatrogenic Creutzfeldt-Jakob disease patients. METHODS: Temporal and spatial development of EEG patterns in 4 patients with sporadic Creutzfeldt-Jakob disease and 2 patients with iatrogenic Creutzfeldt-Jakob disease due to implantation of contaminated brain depth electrodes were investigated. A total of 56 EEGs were analyzed, over time spans ranging from 1272 to 3 days prior to death. RESULTS: Frontal intermittent rhythmical delta activity (FIRDA) was seen at early timepoints in 4/6 patients and might represent an early EEG pattern that is associated, with human prion diseases. EEG patterns associated with CJD are sensitive to midazolam. Initial EEG changes were seen at the site of prion exposure in iatrogenic Creutzfeldt-Jakob disease patients, before they could be observed at distant sites, suggesting that prion disease was initiated at the site of prion exposure. CONCLUSIONS: Serial EEG recordings are a valuable tool not only in the early diagnosis of sporadic CJD, but also in the determination of prion exposure in iatrogenic Creutzfeldt-Jakob disease. SIGNIFICANCE: FIRDA occur at an early stage of CJD and are progressively replaced by the classical PSWC. The EEG patterns of CJD are sensitive to midazolam. The initial EEG changes in iatrogenic CJD are seen at the site of prion exposure.

Adult↗