Typical Creutzfeldt-Jakob Disease Research Articles

Development of an Automated Capillary Immunoassay to Detect Prion Glycotypes in Creutzfeldt-Jakob Disease

Creutzfeldt-Jakob disease (CJD) comprises a group of transmissible neurodegenerative diseases with vast phenotypic diversity. Sporadic CJD heterogeneity is predominantly influenced by the genotype at codon 129 of the prion-encoding gene and the molecular weight of PrPSc fragments after protease digestion, resulting in a classification of 6 subtypes of CJD (MM1, MM2, MV1, MV2, VV1, and VV2). The majority of cases with CJD can be distinguished using this classification system. However, a number of reported CJD cases are phenotypically unique from others within their same subtype, such as variably protease-sensitive prionopathies, or exist as a mixture of subtypes within the same patient. Western blotting of brain tissue, along with the genotyping of codon 129 of the prion-encoding gene, is considered the “gold standard” for the biochemical characterization of CJD. Western blotting requires a significant amount of prion protein for detection, is labor-intensive, and is also associated with high interassay variability. In addition to these limitations, a growing body of research suggests that unique subtypes of CJD are often undetected or misdiagnosed using standard diagnostic western blotting protocols. Consequently, we successfully optimized and developed a capillary-based western assay using the JESS Simple Western (ProteinSimple) to detect and characterize prion proteins from patients with CJD. We found that this novel assay consistently differentiated CJD type 1 and type 2 cases with a limit of detection 10 to 100× higher than traditional western blotting. Cases with CJD in which type 1 and type 2 coexist within the same brain region can be detected using type 1-specific and type 2-specific antibodies, and we found that there was remarkable specificity for the detection of cases with variably protease-sensitive prionopathy. The assay presented displays outstanding sensitivity, allowing for the preservation of valuable samples and enhancing current detection methods.

Defining the Prion Type of Fatal Familial Insomnia.

Fatal familial insomnia (FFI) belongs to the genetic human transmissible spongiform encephalopathies (TSE), such as genetic Creutzfeldt-Jakob disease (CJD) or Gerstmann-Straeussler-Scheinker syndrome (GSS). Here, we analyzed the properties of the pathological prion protein in six FFI cases by Western blot analysis, a protein aggregate stability assay, and aggregate deposition characteristics visualized with the paraffin-embedded tissue blot. While in all cases the unglycosylated fragment in Western blot analysis shared the same size with sporadic CJD prion type 2, the reticular/synaptic deposition pattern of the prion aggregates resembled the ones found in sporadic CJD type 1 (CJD types according to the Parchi classification from 1999). Regarding the conformational stability against denaturation with GdnHCl, FFI prion aggregates resembled CJD type 1 more than type 2. Our results suggest that the size of the proteinase-K-resistant fragments is not a valid criterion on its own. Additional criteria supplying information about conformational differences or similarities need to be taken into account. FFI may resemble a prion type with its own conformation sharing properties partly with type 1 and type 2 prions.

Novel Morphological Glial Alterations in the Spectrum of Prion Disease Types: A Focus on Common Findings.

Human prion diseases are a group of rare fatal neurodegenerative diseases with sporadic, genetic, and acquired forms. They are neuropathologically characterized by pathological prion protein accumulation, neuronal death, and vacuolation. Classical immunological response has long been known not to play a major in prion diseases; however, gliosis is known to be a common feature although variable in extent and poorly described. In this investigation, astrogliosis and activated microglia in two brain regions were assessed and compared with non-neurologically affected patients in a representative sample across the spectrum of Creutzfeldt–Jakob disease (CJD) forms and subtypes in order to analyze the influence of prion strain on pathological processes. In this report, we choose to focus on features common to all CJD types rather than the diversity among them. Novel pathological changes in both glial cell types were found to be shared by all CJD types. Microglial activation correlated to astrogliosis. Spongiosis, but not pathological prion protein deposition, correlated to both astrogliosis and microgliosis. At the ultrastructural level, astrocytic glial filaments correlated with pathological changes associated with prion disease. These observations confirm that neuroglia play a prominent role in the neurodegenerative process of prion diseases, regardless of the causative prion type.

The characterization of AD/PART co-pathology in CJD suggests independent pathogenic mechanisms and no cross-seeding between misfolded A\u03b2 and prion proteins

Current evidence indicating a role of the human prion protein (PrP) in amyloid-beta (Aβ) formation or a synergistic effect between Aβ and prion pathology remains controversial. Conflicting results also concern the frequency of the association between the two protein misfolding disorders and the issue of whether the apolipoprotein E gene (APOE) and the prion protein gene (PRNP), the major modifiers of Aβ- and PrP-related pathologies, also have a pathogenic role in other proteinopathies, including tau neurofibrillary degeneration. Here, we thoroughly characterized the Alzheimer’s disease/primary age-related tauopathy (AD/PART) spectrum in a series of 450 cases with definite sporadic or genetic Creutzfeldt-Jakob disease (CJD). Moreover, we analyzed: (i) the effect of variables known to affect CJD pathogenesis and the co-occurring Aβ- and tau-related pathologies; (II) the influence of APOE genotype on CJD pathology, and (III) the effect of AD/PART co-pathology on the clinical CJD phenotype. AD/PART characterized 74% of CJD brains, with 53.3% and 8.2% showing low or intermediate-high levels of AD pathology, and 12.4 and 11.8% definite or possible PART. There was no significant correlation between variables affecting CJD (i.e., disease subtype, prion strain, PRNP genotype) and those defining the AD/PART spectrum (i.e., ABC score, Thal phase, prevalence of CAA and Braak stage), and no difference in the distribution of APOE ε4 and ε2 genotypes among CJD subtypes. Moreover, AD/PART co-pathology did not significantly affect the clinical presentation of typical CJD, except for a tendency to increase the frequency of cognitive symptoms. Altogether, the present results seem to exclude an increased prevalence AD/PART co-pathology in sporadic and genetic CJD, and indicate that largely independent pathogenic mechanisms drive AD/PART and CJD pathology even when they coexist in the same brain.

The Role of the Mammalian Prion Protein in the Control of Sleep.

Sleep disruption is a prevalent clinical feature in many neurodegenerative disorders, including human prion diseases where it can be the defining dysfunction, as in the case of the “eponymous” fatal familial insomnia, or an early-stage symptom as in certain types of Creutzfeldt-Jakob disease. It is important to establish the role of the cellular prion protein (PrPC), the key molecule involved in prion pathogenesis, within the sleep-wake system in order to understand fully the mechanisms underlying its contribution to both healthy circadian rhythmicity and sleep dysfunction during disease. Although severe disruption to the circadian rhythm and melatonin release is evident during the pathogenic phases of some prion diseases, untangling whether PrPC plays a role in circadian rhythmicity, as suggested in mice deficient for PrPC expression, is challenging given the lack of basic experimental research. We provide a short review of the small amount of direct literature focused on the role of PrPC in melatonin and circadian rhythm regulation, as well as suggesting mechanisms by which PrPC might exert influence upon noradrenergic and dopaminergic signaling and melatonin synthesis. Future research in this area should focus upon isolating the points of dysfunction within the retino-pineal pathway and further investigate PrPC mediation of pinealocyte GPCR activity.

Report and literature review on two cases with different kinds of Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD), also known as corticostriate spinal degeneration, subacute spongiform encephalopathy or infectious spongiform encephalopathy, is a type of degenerative disease of the central nervous system caused by prion protein (PrP) infection, which is the most common type of human PrP disease. CJD is genetic and infectious, and is one of the most common causes of rapid progressive dementia with rare clinical occurrence. Herein, we report the clinical conditions of 2 cases of patients with different type of CJD we treated and followed up recently, and a review of relevant literature. The patient in case 1 was admitted due to ‘dizziness with hypomnesis, and mental and behavior disorder’. He was considered to suffer from a central nervous system infection - a viral encephalitis, but one month later, a repeated cranial MRI showed lace sign of bilateral frontotemporal parietal lobe in DWI sequence, an AEEG indicated periodic synchronous discharge, and the detection of cerebrospinal fluid 14-3-3 protein was positive. It was suggested to be diagnosed as the sporadic CJD. The patient in case 2 was admitted because of ‘progressive hypomnesis’. Cerebrospinal fluid 14-3-3 protein detection was negative, but the V203I-related mutation was found in the PRNP gene detection. The patient was suggested to be diagnosed as genetic CJD. Both patients died in a short time. An earlier diagnosis can provide a time window for treatment, and avoid unnecessary transmission in hospital, as well as doctor-patient dispute.

Prion-specific and surrogate CSF biomarkers in Creutzfeldt-Jakob disease: diagnostic accuracy in relation to molecular subtypes and analysis of neuropathological correlates of p-tau and A\u03b242 levels

The differential diagnosis of Creutzfeldt-Jakob disease (CJD) from other, sometimes treatable, neurological disorders is challenging, owing to the wide phenotypic heterogeneity of the disease. Real-time quaking-induced prion conversion (RT-QuIC) is a novel ultrasensitive in vitro assay, which, at variance with surrogate neurodegenerative biomarker assays, specifically targets the pathological prion protein (PrPSc). In the studies conducted to date in CJD, cerebrospinal fluid (CSF) RT-QuIC showed good diagnostic sensitivity (82–96%) and virtually full specificity. In the present study, we investigated the diagnostic value of both prion RT-QuIC and surrogate protein markers in a large patient population with suspected CJD and then evaluated the influence on CSF findings of the CJD type, and the associated amyloid-β (Aβ) and tau neuropathology. RT-QuIC showed an overall diagnostic sensitivity of 82.1% and a specificity of 99.4%. However, sensitivity was lower in CJD types linked to abnormal prion protein (PrPSc) type 2 (VV2, MV2K and MM2C) than in typical CJD (MM1). Among surrogate proteins markers (14-3-3, total (t)-tau, and t-tau/phosphorylated (p)-tau ratio) t-tau performed best in terms of both specificity and sensitivity for all sCJD types. Sporadic CJD VV2 and MV2K types demonstrated higher CSF levels of p-tau when compared to other sCJD types and this positively correlated with the amount of tiny tau deposits in brain areas showing spongiform change. CJD patients showed moderately reduced median Aβ42 CSF levels, with 38% of cases having significantly decreased protein levels in the absence of Aβ brain deposits. Our results: (1) support the use of both RT-QuIC and t-tau assays as first line laboratory investigations for the clinical diagnosis of CJD; (2) demonstrate a secondary tauopathy in CJD subtypes VV2 and MV2K, correlating with increased p-tau levels in the CSF and (3) provide novel insight into the issue of the accuracy of CSF p-tau and Aβ42 as markers of brain tauopathy and β-amyloidosis.

Creutzfeldt-Jakob disease.

This review will explore the clinical and pathological findings of the various forms of Creutzfeldt-Jakob disease (CJD). Clinical findings of CJD are characterized by rapidly progressive cognitive dysfunction, diffusion-weighted magnetic resonance imaging (DWI) hyperintensity, myoclonus, periodic sharp-wave complexes on electroencephalogram and akinetic mutism state. Neuropathologic findings of CJD are characterized by spongiform changes in gray matter, gliosis-particularly hypertrophic astrocytosis-neuropil rarefaction, neuron loss and prion protein (PrP) deposition. The earliest pathological symptom observed by HE staining in the cerebral cortex is spongiform change. This spongiform change begins several months before clinical onset, and is followed by gliosis. Subsequently, neuropil rarefaction appears, followed by neuron loss. Regions showing fine vacuole-type spongiform change reflect synaptic-type PrP deposition and type 1 PrPSc deposition, whereas regions showing large confluent vacuole-type spongiform changes reflect perivacuolar-type PrP deposition and type 2 PrPSc deposition. Hyperintensities of the cerebral gray matter observed in DWI indicate the pathology of the spongiform change in CJD. The cerebral cortical lesions with large confluent vacuoles and type 2 PrPSc show higher brightness and more continuous hyperintensity on DWI than those with fine vacuoles and type 1 PrPSc . CJD cases showing diffuse myelin pallor of cerebral white matter have been described as panencephalopathic-type, and this white matter pathology is mainly due to secondary degeneration caused by cerebral cortical involvement, particularly in regard to neuron loss. In conclusion, clinical and neuroimaging findings and neuropathologic observations are well matched in both typical and atypical cases in CJD. The clinical diagnosis of CJD is relatively easy for typical CJD cases such as the MM1-type. However, even in atypical cases it seems that clinical findings can be used for an accurate diagnosis.

Diagnostic Accuracy of a Combined Analysis of Cerebrospinal Fluid t-PrP, t-tau, p-tau, and Aβ42 in the Differential Diagnosis of Creutzfeldt-Jakob Disease from Alzheimer's Disease with Emphasis on Atypical Disease Variants.

According to recent studies, the determination of cerebrospinal fluid (CSF) total tau (t-tau)/phosphorylated tau (p-tau) ratio and total prion protein (t-PrP) levels significantly improves the accuracy of the diagnosis of Alzheimer’s disease (AD) in atypical cases with clinical or laboratory features mimicking Creutzfeldt-Jakob disease (CJD). However, this has neither been validated nor tested in series including atypical CJD variants. Furthermore, the added diagnostic value of amyloid-β (Aβ)42 remains unclear. To address these issues, we measured t-PrP, 14-3-3, t-tau, p-tau, and Aβ42 CSF levels in 45 typical and 44 atypical/rapidly progressive AD patients, 54 typical and 54 atypical CJD patients, and 33 controls. CJD patients showed significantly lower CSF t-PrP levels than controls and AD patients. Furthermore, atypical CJD was associated with lower t-PrP levels in comparison to typical CJD. T-tau, 14-3-3, or t-PrP alone yielded, respectively, 80.6, 63.0, and 73.0% sensitivity and 75.3, 92.1, and 75% specificity in distinguishing AD from CJD. On receiver operating characteristic (ROC) curve analyses of biomarker combinations, the (t-tau×Aβ42)/(p-tau×t-PrP) ratio achieved the best accuracy, with 98.1% sensitivity and 97.7% specificity overall, and 96.2% sensitivity and 95.5% specificity for the “atypical” disease groups. Our results show that the combined analysis of CSF t-PrP, t-tau, p-tau, and Aβ42 is clinically useful in the differential diagnosis between CJD and AD. Furthermore, the finding of reduced CSF t-PrP levels in CJD patients suggest that, likewise Aβ42 in AD, CSF t-PrP levels reflect the extent of PrPc conversion into abnormal PrP (PrPSc) and the burden of PrPSc deposition in CJD.

Analysis of Conformational Stability of Abnormal Prion Protein Aggregates across the Spectrum of Creutzfeldt-Jakob Disease Prions.

The wide phenotypic variability of prion diseases is thought to depend on the interaction of a host genotype with prion strains that have self-perpetuating biological properties enciphered in distinct conformations of the misfolded prion protein PrP(Sc) This concept is largely based on indirect approaches studying the effect of proteases or denaturing agents on the physicochemical properties of PrP(Sc) aggregates. Furthermore, most data come from studies on rodent-adapted prion strains, making current understanding of the molecular basis of strains and phenotypic variability in naturally occurring diseases, especially in humans, more limited. To fill this gap, we studied the effects of guanidine hydrochloride (GdnHCl) and heating on PrP(Sc) aggregates extracted from 60 sporadic Creutzfeldt-Jakob disease (CJD) and 6 variant CJD brains. While denaturation curves obtained after exposure of PrP(Sc) to increasing GdnHCl concentrations showed similar profiles among the 7 CJD types analyzed, PrP(Sc) exposure to increasing temperature revealed significantly different and type-specific responses. In particular, MM1 and VV2, the most prevalent and fast-replicating CJD types, showed stable and highly resistant PrP(Sc) aggregates, whereas VV1, a rare and slowly propagating type, revealed unstable aggregates that easily dissolved at low temperature. Taken together, our results indicate that the molecular interactions mediating the aggregation state of PrP(Sc), possibly enciphering strain diversity, are differently targeted by GdnHCl, temperature, and proteases. Furthermore, the detected positive correlation between the thermostability of PrP(Sc) aggregates and disease transmission efficiency makes inconsistent the proposed hypothesis that a decrease in conformational stability of prions results in an increase in their replication efficiency. Prion strains are defined as infectious isolates propagating distinctive phenotypic traits after transmission to syngeneic hosts. Although the molecular basis of prion strains is not fully understood, it is largely accepted that variations in prion protein conformation drive the molecular changes leading to the different phenotypes. In this study, we exposed abnormal prion protein aggregates encompassing the spectrum of human prion strains to both guanidine hydrochloride and thermal unfolding. Remarkably, while exposure to increasing temperature revealed significant strain-specific differences in the denaturation profile of the protein, treatment with guanidine hydrochloride did not. The findings suggest that thermal and chemical denaturation perturb the structure of prion protein aggregates differently. Moreover, since the most thermostable prion protein types were those associated with the most prevalent phenotypes and most rapidly and efficiently transmitting strains, the results suggest a direct correlation between strain replication efficiency and the thermostability of prion protein aggregates.

Management of Dysphagia in a Patient with Creutzfeldt-Jakob Disease

Creutzfeldt-Jakob disease (CJD) is an incredibly rare and progressive neurodegenerative disorder that belongs to a category of diseases known as “transmissible spongiform encephalopathies”, or prion diseases. This inevitably fatal disease affects approximately one person per million annually worldwide, with an incidence of 300 cases yearly in the United States. CJD is characterized by the excessive accumulation of an abnormal natural occurring protein, PrPc. As the disease process advances, destruction of the cerebral architecture in sensory, motor, and associated areas can lead to oropharyngeal dysphagia. Management of this condition is mainly palliative, and a certain subset of patients will require a gastrostomy feeding tube for enteral nutrition. Our case discusses challenging issues with regards to GI management in these individuals, including options for enteric feeding. A 57-year-old female with a PMH significant for MDD, DM, HTN, and hypothyroidism presented to the psychiatry ward at the behest of her family due to personality changes. The patient's family history was pertinent for her grandmother dying at the age of 36 of an unknown rapidly progressing disease that lasted over the span of 36 months. The patient began exhibiting symptoms of progressive neurological decline over a period of three months. The patient eventually became non-verbal and semi-catatonic. Given the patient's family history, she then underwent evaluation for CJD. CSF studies for Tau and 14-3-3 protein returned positive. GI was consulted for endoscopy with PEG placement due to worsening and non-reversible dysphagia. Given her diagnosis, it was decided that percutaneous fluoroscopically guided gastrostomy tube placement was the safest course of action. The patient was subsequently admitted to hospice. This case details the challenges that a gastroenterology service can encounter in the evaluation and treatment of extremely rare CJD cases. There is still very little literature detailing appropriate invasive measures for these patients, and the specific type of CJD cannot be diagnosed without a post-mortem brain biopsy. In cases of variant CJD, there is evidence that lymphatic tissue such as tonsils, Peyer's patches, and the appendix store pathological prions, thus increasing the risk of exposing and contaminating endoscopy instruments. Given this risk factor, for patients with known or suspected CJD, percutaneous gastrostomy guided by ultrasound and fluoroscopy is the most preferable method of placement. Per current literature, endoscopically assisted PEG placement should be used only as a last resort, and the instrument should be placed in quarantine until the post-mortem diagnosis is confirmed. If vCJD is confirmed, the endoscope cannot be used again and should remain in quarantine indefinitely for laboratory analysis.

Report about Four Novel Mutations in the Prion Protein Gene

Background/Aims: Since detection of the prion protein gene (PRNP) more than 30 mutations have been discovered. Some have only been found in single case reports without known intrafamilial accumulation or neuropathological proof so that the causal connection between mutation and disease could not be proved. Those patients often present atypical clinical phenotypes, and it is not unusual that they are classified as diseases other than Creutzfeldt-Jakob disease (CJD). Methods: Cases of suspected CJD have been reported to the national reference center for prion diseases. Clinical and diagnostic data were collected, and a classification of definite, possible or probable prion disease was made. Molecular analysis of PRNP was performed by capillary sequencing. Results: We have described 4 cases with atypical clinical and diagnostic findings and unknown mutations in PRNP so far. Conclusion: Three patients fulfilled the criteria of probable CJD, and 1 patient fulfilled the criteria of possible CJD but the clinical picture in none of the patients was typical CJD; hence, it remained questionable whether the mutations were causal of the disease.

Can Mortality Data Provide Reliable Indicators for Creutzfeldt-Jakob Disease Surveillance? A Study in France from 2000 to 2008

Background: Surveillance of Creutzfeldt-Jakob disease (CJD) is still an important issue because of the variant CJD epidemic, which is in decline and also because of the emergence of novel forms of animal transmissible spongiform encephalopathy with zoonotic potential and the risk of nosocomial and blood transfusion-related transmission. Active surveillance has been implemented in most European countries and requires important human resources and funding. Here, we studied whether national mortality and morbidity statistics can be used as reliable indicators. Methods: CJD data collected by the French national CJD surveillance centre were compared with data registered in the national mortality statistics. Results: From 2000 to 2008, the two sources reported fairly similar numbers of CJD deaths. However, analysis of individual data showed important between-sources disagreement. Nearly 24% of CJD reported by the mortality register were false-positive diagnoses and 21.6% of the CJD cases diagnosed by the surveillance centre were not registered as CJD in the national mortality statistics. One out of 22 variant CJD cases was not reported as having any type of CJD in the mortality statistics. Conclusions:These findings raise doubt about the possibility of a reliable CJD surveillance only based on mortality data.

Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) occurs in Australia at a rate of 1.17 per annum. There are three main subtypes: sporadic, iatrogenic and familial. A clinical definition of CJD exists which incorporates clinical history and examination, MRI and14-3-3 protein findings. Around 15% of cases are due to a pathogenic mutation in the prion protein gene (PRNP). Iatrogenic CJD can be either due to direct inoculation or peripheral exposure. vCJD is a subtype of iatrogenic CJD occurring predominantly in the UK and associated with a younger age group. CJD is due to the formation of an abnormal form of the prion protein, PrP^res, which has a high beta pleated sheet content and propagates within the brain through a conversion reaction of normal PrP^c. PrP^res is resistant to protease degradation and as such, handling of CJD tissues is usually restricted to laboratories trained in CJD. Samples are categorised as class 6.2 infectious substances and are category B. The definitive diagnosis of CJD is established following post-mortem neuropathological examination. The classical CJD triad is neuronal degeneration, gliosis and PrP^res deposition as indicated by immunoperoxidase. Variation on these changes can occur depending on the type of CJD. Additional information can be obtained by Western blotting and PET blot techniques.

Similarities between Forms of Sheep Scrapie and Creutzfeldt-Jakob Disease Are Encoded by Distinct Prion Types

Transmissible spongiform encephalopathies such as scrapie in sheep, Creutzfeldt-Jakob disease (CJD) in humans, and bovine sporadic encephalopathy in cattle are characterized by the accumulation of a misfolded protein: the pathological prion protein. Ever since bovine sporadic encephalopathy was discovered as the likely cause of the new variant of CJD in humans, parallels between human and animal transmissible spongiform encephalopathies must be viewed under the aspect of a disease risk for humans. In our study we have compared prion characteristics of different forms of sheep scrapie with those of different phenotypes of sporadic CJD. The disease characteristics of sporadic CJD depend considerably on the prion type 1 or 2. Our results show that there are obvious parallels between sporadic CJD type 1 and the so-called atypical/Nor98 scrapie. These parelleles apply to the deposition form of pathological prion protein in the brain, detected by the paraffin-embedded-tissue blot and the prion aggregate stability with regard to denaturation by the chaotropic salt guanidine hydrochloride. The same applies to sporadic CJD type 2 and classical scrapie. The observed parallels between types of sporadic CJD and types of sheep scrapie demonstrate that distinct groups of prion disease exist in different species. This should be taken into consideration when discussing interspecies transmission.

Prospects for Preventative Vaccines Against Prion Diseases

Emergence of variant type of Creutzfeldt-Jakob disease (vCJD) in humans due to infection from bovine spongiform encephalopathy contaminated beef and recent reports of human-to-human transmission of vCJD via blood transfusion have raised great concern about an epidemic of vCJD. The disease is currently difficult to diagnose during pre-clinical stages and requires a very long incubation period for neurological symptoms to be evident. This therefore suggests that the disease is already latently spreading and that opportunity for infection is thus growing among human populations. Interestingly, passive immunization with antibodies against prion protein (PrP), a major component of the prion infectious agents, was shown to protect mice from infection, indicating the possibility of prion vaccines. However, PrP is a host protein therefore immune tolerance to PrP has hampered development of them. Here, the so far reported attempts to overcome the tolerance to elicit protective immunity to prions are briefly reviewed.

An unusually presenting case of sCJD—The VV1 subtype

Creutzfeldt–Jakob disease (CJD) is a rapidly progressive neurodegenerative disease caused by prions. Typically CJD presents with a triad of rapidly progressive dementia, abnormal movements (e.g., myoclonus) and electroencephalographic (EEG) changes. Recently, CJD has been subdivided into subtypes based on host genetic polymorphisms and the characteristics of the pathological prion protein. Different subtypes likely have different clinical and laboratory presentations. We describe a case of sporadic CJD of the VV1 subtype. We describe our patient's clinical symptoms, time course, laboratory workup, structural and functional neuroimaging data, EEG data and CJD biomarkers. Our patient presented with clinical symptoms atypical for CJD. Because of that, her clinical symptoms were initially attributed to psychiatric reasons. After extensive clinical and laboratory investigation, we concluded that the patient probably had CJD. Postmortem neuropathological results confirmed this clinical hypothesis. We compare our patient's clinical, laboratory and neuroimaging data to the data on typical CJD as well as the data on the few CJD VV1 cases described in the literature. We discuss our case's relevance to the diagnosis of CJD.

Characterisation of new monoclonal antibodies reacting with prions from both human and animal brain tissues

Post-mortem diagnosis of transmissible spongiform encephalopathies (prion diseases) is primarily based on the detection of a protease resistant, misfolded disease associated isoform (PrP Sc) of the prion protein (PrP C) on neuronal cells. These methods depend on antibodies directed against PrP C and capable of reacting with PrP Sc in situ (immunohistochemistry on nervous tissue sections) or with the unfolded form of the protein (western and paraffin embedded tissue (PET) blotting). Here, high-affinity monoclonal antibodies (mAbs 1.5D7, 1.6F4) were produced against synthetic PrP peptides in wild-type mice and used for western blotting and immunohistochemistry to detect several types of human prion-disease associated PrP Sc, including sporadic Creutzfeldt-Jakob Disease (CJD) (subtypes MM1 and VV2), familial CJD and Gerstmann-Sträussler-Scheinker (GSS) disease PrP Sc as well as PrP Sc of bovine spongiform encephalopathy (bovine brain), scrapie (ovine brain) and experimental scrapie in hamster and in mice. The antibodies were also used for PET-blotting in which PrP Sc blotted from brain tissue sections onto a nitrocellulose membrane is visualized with antibodies after protease and denaturant treatment allowing the detection of protease resistant PrP forms (PrP RES) in situ. Monoclonal antibodies 1.5D7 and 1.6F4 were raised against the reported epitope (PrP153–165) of the commercial antibody 6H4. While 1.5D7 and 1.6F4 were completely inhibitable by PrP153–165, 6H4 was not, indicating that the specificity of 6H4 is not defined completely by PrP153–165. The two antibodies performed similarly to 6H4 in western blotting with human samples, but showed less reactivity and enhanced background staining with animal samples in this method. In immunohistochemistry 1.5D7 and 1.6F4 performed better than 6H4 suggesting that the binding affinity of 1.5D7 and 1.6F4 with native (aggregated) PrP Sc in situ was higher than that of 6H4. On the other hand in PET-blotting, 6H4 reached the same level of reactivity as 1.5D7 and 1.6F4. This shows that 6H4 needs denatured PrP RES to reach maximal reactivity, confirming earlier results. As an exception, human PrP RES still reacted relatively poorly with 6H4 in PET-blotting, while 1.5D7 and 1.6F4 reacted well with PrP RES from most human CJD types. Taken together this implies that the binding epitope of 1.5D7 and 1.6F4 is accessible in the aggregates of undenatured PrP Sc (IHC) while the binding site of 6H4 is at least partly inaccessible. In techniques incorporating a denaturing and/or disaggregating step 6H4 showed good binding indicating increased accessibility of the binding site. An exception to this is human samples in PET-blotting suggesting that huPrP RES might not be as easily unfolded by denaturation as BSE and scrapie PrP RES. Also of interest was the ability of 1.5D7 and 1.6F4 to discriminate between two allelic variants of PrP CJD Sc (VV vs. MM) in immunohistochemistry as opposed to the normally used antibody 3F4.

Does the Presentation of Creutzfeldt-Jakob Disease Vary by Age or Presumed Etiology? A Meta-Analysis of the Past 10 Years

Does the Presentation of Creutzfeldt-Jakob Disease Vary by Age or Presumed Etiology? A Meta-Analysis of the Past 10 Years

Cholinesterases and Unified Neurophysics

The enigmatic diseases of the ‘Mad Cow’ type (BSE) were approached from the fundamental level of ethereal particle spin (chirality). A revised definition of chirality then gave a logical explanation for structure and function in both physics and biology. Cholinesterases (ChEs) appeared to govern stereo-chemical hydrodynamics by the release of free protons to activate hem-transported molecular oxygen. Oxidation will increase stability of bio-molecules and recycle hydrogen to water. Biology stands for the only break in universal symmetry (parity violation) by its ChE-oxidative hydrodynamics and explains the matter-antimatter issue. In the brain, basic physical events will be inhibited, delayed or converted by ChE’s hydrodynamic autonomy, which basically equals continuous inflammation. The pathophysiology in a lot of neurological diseases of the Bowine Spongioform Encephalitis -scrapie- Alzheimer’s disease - Creutzfeldt-Jakob Disease type in cattle, sheep and man, like the relentless process of aging by long-term oxidative effects was elucidated by the present short glimpses into physics.