scholarly journals Detection of RNA in the Plasma of Patients with Sporadic Creutzfeldt–Jakob Disease, Gerstmann–Straüssler Syndrome and Other Non-Transmissible Spongiform Encephalopathy Brain Disorders

2010 ◽  
Vol 3 ◽  
pp. MBI.S4043
Author(s):  
Kazuo Tsukui ◽  
Yasushi Iwasaki ◽  
Masamitsu Nagaoka ◽  
Kenji Tadokoro

The infectious agent of transmissible spongiform encephalopathy (TSE) was assumed to be the aggregate of abnormal prion protein isoform (PrPsc). We observed that lowering the pH of 3% SDS-inoculated plasma or brain homogenate after PK digestion to 4.5 (acidic SDS condition) enabled to precipitate proteinase K-resistant prion protein (PrPres) in plasma as well as PrPres in the brain with synthetic poly-A RNA as affinity aggregate. Therefore, we determined if RNA molecules could be used for discriminating TSE patients from healthy individuals. We also examined the plasma of patients with classical Creutzfeldt–Jakob disease (CJD) and other brain disorders who were not diagnosed with TSE. The results indicated that RNA approximately 1.5–2.0 kb in length was commonly observed in the plasma of patients with brain disorders but was not detected in the plasma of healthy volunteers. Enhanced expression of RNA and its protection from endogenous nucleases might occur in the former group of patients. Moreover, we speculate that the non-transmissible neuronal disorders overlap with prion diseases.

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Francesca Properzi ◽  
Maurizio Pocchiari

Transmissible spongiform encephalopathy (TSE) or prion diseases are fatal rare neurodegenerative disorders affecting man and animals and caused by a transmissible infectious agent. TSE diseases are characterized by spongiform brain lesions with neuronal loss and the abnormal deposition in the CNS, and to less extent in other tissues, of an insoluble and protease resistant form of the cellular prion protein (PrPC), namedPrPTSE. In man, TSE diseases affect usually people over 60 years of age with no evident disease-associated risk factors. In some cases, however, TSE diseases are unequivocally linked to infectious episodes related to the use of prion-contaminated medicines, medical devices, or meat products as in the variant Creutzfeldt-Jakob disease (CJD). Clinical signs occur months or years after infection, and during this silent periodPrPTSE, the only reliable marker of infection, is not easily measurable in blood or other accessible tissues or body fluids causing public health concerns. To overcome the limit ofPrPTSEdetection, several highly sensitive assays have been developed, but attempts to apply these techniques to blood of infected hosts have been unsuccessful or not yet validated. An update on the latest advances for the detection of misfolded prion protein in body fluids is provided.


2008 ◽  
Vol 416 (2) ◽  
pp. 297-305 ◽  
Author(s):  
Sabrina Cronier ◽  
Nathalie Gros ◽  
M. Howard Tattum ◽  
Graham S. Jackson ◽  
Anthony R. Clarke ◽  
...  

Disease-related PrPSc [pathogenic PrP (prion protein)] is classically distinguished from its normal cellular precursor, PrPC(cellular PrP) by its detergent insolubility and partial resistance to proteolysis. Although molecular diagnosis of prion disease has historically relied upon detection of protease-resistant fragments of PrPSc using PK (proteinase K), it is now apparent that a substantial fraction of disease-related PrP is destroyed by this protease. Recently, thermolysin has been identified as a complementary tool to PK, permitting isolation of PrPSc in its full-length form. In the present study, we show that thermolysin can degrade PrPC while preserving both PK-sensitive and PK-resistant isoforms of disease-related PrP in both rodent and human prion strains. For mouse RML (Rocky Mountain Laboratory) prions, the majority of PK-sensitive disease-related PrP isoforms do not appear to contribute significantly to infectivity. In vCJD (variant Creutzfeldt–Jakob disease), the human counterpart of BSE (bovine spongiform encephalopathy), up to 90% of total PrP present in the brain resists degradation with thermolysin, whereas only ∼15% of this material resists digestion by PK. Detection of PK-sensitive isoforms of disease-related PrP using thermolysin should be useful for improving diagnostic sensitivity in human prion diseases.


2017 ◽  
Vol 91 (21) ◽  
Author(s):  
Allison Kraus ◽  
Gregory J. Raymond ◽  
Brent Race ◽  
Katrina J. Campbell ◽  
Andrew G. Hughson ◽  
...  

ABSTRACT Accumulation of fibrillar protein aggregates is a hallmark of many diseases. While numerous proteins form fibrils by prion-like seeded polymerization in vitro, only some are transmissible and pathogenic in vivo. To probe the structural features that confer transmissibility to prion protein (PrP) fibrils, we have analyzed synthetic PrP amyloids with or without the human prion disease-associated P102L mutation. The formation of infectious prions from PrP molecules in vitro has required cofactors and/or unphysiological denaturing conditions. Here, we demonstrate that, under physiologically compatible conditions without cofactors, the P102L mutation in recombinant hamster PrP promoted prion formation when seeded by minute amounts of scrapie prions in vitro. Surprisingly, combination of the P102L mutation with charge-neutralizing substitutions of four nearby lysines promoted spontaneous prion formation. When inoculated into hamsters, both of these types of synthetic prions initiated substantial accumulation of prion seeding activity and protease-resistant PrP without transmissible spongiform encephalopathy (TSE) clinical signs or notable glial activation. Our evidence suggests that PrP's centrally located proline and lysine residues act as conformational switches in the in vitro formation of transmissible PrP amyloids. IMPORTANCE Many diseases involve the damaging accumulation of specific misfolded proteins in thread-like aggregates. These threads (fibrils) are capable of growing on the ends by seeding the refolding and incorporation of the normal form of the given protein. In many cases such aggregates can be infectious and propagate like prions when transmitted from one individual host to another. Some transmitted aggregates can cause fatal disease, as with human iatrogenic prion diseases, while other aggregates appear to be relatively innocuous. The factors that distinguish infectious and pathogenic protein aggregates from more innocuous ones are poorly understood. Here we have compared the combined effects of prion seeding and mutations of prion protein (PrP) on the structure and transmission properties of synthetic PrP aggregates. Our results highlight the influence of specific sequence features in the normally unstructured region of PrP that influence the infectious and neuropathogenic properties of PrP-derived aggregates.


2006 ◽  
Vol 53 (2) ◽  
pp. 399-405 ◽  
Author(s):  
Stéphane Lezmi ◽  
Frédéric Ronzon ◽  
Anna Bencsik ◽  
Alexandre Bedin ◽  
Didier Calavas ◽  
...  

To study the pathogenesis of bovine spongiform encephalopathy infection in small ruminants, two Lacaune sheep with the AA136RR154QQ171 and one with the AA136RR154RR171 genotype for the prion protein, were inoculated with a brain homogenate from a French cattle BSE case by peripheral routes. Sheep with the ARQ/ARQ genotype are considered as susceptible to prion diseases contrary to those with the ARR/ARR genotype. The accumulation of disease-associated prion protein (PrP(d)) was analysed by biochemical and immunohistochemical methods. No PrP(d) accumulation was detected in samples from the ARR/ARR sheep 2 years post inoculation. In the two ARQ/ARQ sheep that had scrapie-like clinical symptoms, PrP(d) was found in the central, sympathetic and enteric nervous systems and in lymphoid organs. Remarkably, PrP(d) was also detected in some muscle types as well as in all peripheral nerves that had not been reported previously thus revealing a widespread distribution of BSE-associated PrP(d) in sheep tissues.


2007 ◽  
Vol 88 (10) ◽  
pp. 2905-2914 ◽  
Author(s):  
Victoria A. Lawson ◽  
James D. Stewart ◽  
Colin L. Masters

The unconventional nature of the infectious agent of prion diseases poses a challenge to conventional infection control methodologies. The extraneural tissue distribution of variant and sporadic Creutzfeldt–Jakob disease has increased concern regarding the risk of prion disease transmission via general surgical procedures and highlighted the need for decontamination procedures that can be incorporated into routine processing. In this study, the ability of preparations of enzymatic medical instrument cleaners to reduce the infectivity associated with a rodent-adapted strain of human prion disease, previously reported to be resistant to decontamination, was tested. Efficient degradation of the disease-associated prion protein by enzymatic cleaning preparations required high treatment temperatures (50–60 °C). Standard decontamination methods (1 M NaOH for 1 h or autoclaving at 134 °C for 18 min) reduced infectivity associated with the human-derived prion strain by less than 3 log10 LD50. In contrast, a 30 min treatment with the optimized enzymatic cleaning preparation protocols reduced infectivity by more than 3 log10 LD50 and when used in conjunction with autoclave cycles eliminated detectable levels of infectivity. The development of prion decontamination procedures that are compatible with routine cleaning and sterilization of medical and surgical instruments may reduce the risk of the transmission of prion disease in general surgery.


2002 ◽  
Vol 76 (9) ◽  
pp. 4357-4363 ◽  
Author(s):  
Michael B. A. Oldstone ◽  
Richard Race ◽  
Diane Thomas ◽  
Hanna Lewicki ◽  
Dirk Homann ◽  
...  

ABSTRACT Transmissible spongiform encephalopathy or prion diseases are fatal neurodegenerative disorders of humans and animals often initiated by oral intake of an infectious agent. Current evidence suggests that infection occurs initially in the lymphoid tissues and subsequently in the central nervous system (CNS). The identity of infected lymphoid cells remains controversial, but recent studies point to the involvement of both follicular dendritic cells (FDC) and CD11c+ lymphoid dendritic cells. FDC generation and maintenance in germinal centers is dependent on lymphotoxin alpha (LT-α) and LT-β signaling components. We report here that by the oral route, LT-α −/− mice developed scrapie while LT-β −/− mice did not. Furthermore, LT-α −/− mice had a higher incidence and shorter incubation period for developing disease following inoculation than did LT-β −/− mice. Transplantation of lymphoid tissues from LT-β −/− mice, which have cervical and mesenteric lymph nodes, into LT-α −/− mice, which do not, did not alter the incidence of CNS scrapie. In other studies, a virus that is tropic for and alters functions of CD11c+ cells did not alter the kinetics of neuroinvasion of scrapie. Our results suggest that neither FDC nor CD11c+ cells are essential for neuroinvasion after high doses of RML scrapie. Further, it is possible that an as yet unidentified cell found more abundantly in LT-α −/− than in LT-β −/− mice may assist in the amplification of scrapie infection in the periphery and favor susceptibility to CNS disease following peripheral routes of infection.


2017 ◽  
Vol 92 (1) ◽  
Author(s):  
Hideyuki Hara ◽  
Hironori Miyata ◽  
Nandita Rani Das ◽  
Junji Chida ◽  
Tatenobu Yoshimochi ◽  
...  

ABSTRACTConformational conversion of the cellular isoform of prion protein, PrPC, into the abnormally folded, amyloidogenic isoform, PrPSc, is a key pathogenic event in prion diseases, including Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy (BSE) in animals. We previously reported that the octapeptide repeat (OR) region could be dispensable for converting PrPCinto PrPScafter infection with RML prions. We demonstrated that mice transgenically expressing mouse PrP with deletion of the OR region on the PrP knockout background, designated Tg(PrPΔOR)/Prnp0/0mice, did not show reduced susceptibility to RML scrapie prions, with abundant accumulation of PrPScΔOR in their brains. We show here that Tg(PrPΔOR)/Prnp0/0mice were highly resistant to BSE prions, developing the disease with markedly elongated incubation times after infection with BSE prions. The conversion of PrPΔOR into PrPScΔOR was markedly delayed in their brains. These results suggest that the OR region may have a crucial role in the conversion of PrPCinto PrPScafter infection with BSE prions. However, Tg(PrPΔOR)/Prnp0/0mice remained susceptible to RML and 22L scrapie prions, developing the disease without elongated incubation times after infection with RML and 22L prions. PrPScΔOR accumulated only slightly less in the brains of RML- or 22L-infected Tg(PrPΔOR)/Prnp0/0mice than PrPScin control wild-type mice. Taken together, these results indicate that the OR region of PrPCcould play a differential role in the pathogenesis of BSE prions and RML or 22L scrapie prions.IMPORTANCEStructure-function relationship studies of PrPCconformational conversion into PrPScare worthwhile to understand the mechanism of the conversion of PrPCinto PrPSc. We show here that, by inoculating Tg(PrPΔOR)/Prnp0/0mice with the three different strains of RML, 22L, and BSE prions, the OR region could play a differential role in the conversion of PrPCinto PrPScafter infection with RML or 22L scrapie prions and BSE prions. PrPΔOR was efficiently converted into PrPScΔOR after infection with RML and 22L prions. However, the conversion of PrPΔOR into PrPScΔOR was markedly delayed after infection with BSE prions. Further investigation into the role of the OR region in the conversion of PrPCinto PrPScafter infection with BSE prions might be helpful for understanding the pathogenesis of BSE prions.


2005 ◽  
Vol 86 (1) ◽  
pp. 241-246 ◽  
Author(s):  
Robert A. Somerville ◽  
Scott Hamilton ◽  
Karen Fernie

Transmissible spongiform encephalopathies (TSEs), sometimes known as prion diseases, are caused by an infectious agent whose molecular properties have not been determined. Traditionally, different strains of TSE diseases are characterized by a series of phenotypic properties after passage in experimental animals. More recently it has been recognized that diversity in the degree to which an abnormal form of the host protein PrP, denoted PrPSc, is glycosylated and the migration of aglycosyl forms of PrPSc on immunoblots may have some differential diagnostic potential. It has been recognized that these factors are affected by the strain of TSE agent but also by other factors, e.g. location within the brain. This study shows in some cases, but not others, that host PrP genotype has a major influence on the degree of PrPSc glycosylation and migration on gels and provides further evidence of the effect of brain location. Accordingly both the degree of glycosylation and the apparent molecular mass of PrPSc may be of some value for differential diagnosis between TSE strains, but only when host effects are taken into account. Furthermore, the data inform the debate about how these differences arise, and favour hypotheses proposing that TSE agents affect glycosylation of PrP during its biosynthesis.


2001 ◽  
Vol 79 (5) ◽  
pp. 613-628 ◽  
Author(s):  
Peter Mastrangelo ◽  
David Westaway

The prion protein gene Prnp encodes PrPSc, the major structural component of prions, infectious pathogens causing a number of disorders including scrapie and bovine spongiform encephalopathy (BSE). Missense mutations in the human Prnp gene, PRNP, cause inherited prion diseases such as familial Creutzfeldt–Jakob Disease. In uninfected animals, Prnp encodes a GPI-anchored protein denoted PrPC, and in prion infections, PrPCis converted to PrPScby templated refolding. Although Prnp is conserved in mammalian species, attempts to verify interactions of putative PrP-binding proteins by genetic means have proven frustrating in that two independent lines of Prnp gene ablated mice (Prnp0/0mice: ZrchI and Npu) lacking PrPCremain healthy throughout development. This indicates that PrPCserves a function that is not apparent in a laboratory setting or that other molecules have overlapping functions. Shuttling or sequestration of synaptic Cu(II) via binding to N-terminal octapeptide residues and (or) signal transduction involving the fyn kinase are possibilities currently under consideration. A new point of entry into the issue of prion protein function has emerged from identification of a paralog, Prnd, with 25% coding sequence identity to Prnp. Prnd lies downstream of Prnp and encodes the Dpl protein. Like PrPC, Dpl is presented on the cell surface via a GPI anchor and has three α-helices: however, it lacks the conformationally plastic and octapeptide repeat domains present in its well-known relative. Interestingly, Dpl is overexpressed in two other lines of Prnp0/0mice (Ngsk and Rcm0) via intergenic splicing events. These lines of Prnp0/0mice exhibit ataxia and apoptosis of cerebellar cells, indicating that ectopic synthesis of Dpl protein is toxic to CNS neurons: this inference has now been confirmed by the construction of transgenic mice expressing Dpl under the direct control of the PrP promoter. Remarkably, Dpl-programmed ataxia is rescued by wt Prnp transgenes. The interaction between the Prnp and Prnd genes in mouse cerebellar neurons may have a physical correlate in competition between Dpl and PrPCwithin a common biochemical pathway that, when misregulated, leads to apoptosis.Key words: spongiform encephalopathy, neurodegenerative disease, paralogs, scrapie, CJD.


2020 ◽  
Vol 44 ◽  
Author(s):  
Christiane Stehmann ◽  
Matteo Senesi ◽  
Shannon Sarros ◽  
Amelia McGlade ◽  
Marion Simpson ◽  
...  

Nationwide surveillance of Creutzfeldt-Jakob disease and other human prion diseases is performed by the Australian National Creutzfeldt-Jakob Disease Registry (ANCJDR). National surveillance encompasses the period since 1 January 1970, with prospective surveillance occurring from 1 October 1993. Over this prospective surveillance period, considerable developments have occurred in pre-mortem diagnostics; in the delineation of new disease subtypes; and in a heightened awareness of prion diseases in healthcare settings. Surveillance practices of the ANCJDR have evolved and adapted accordingly. This report summarises the activities of the ANCJDR during 2019. Since the ANCJDR began offering diagnostic cerebrospinal fluid (CSF) 14-3-3 protein testing in Australia in September 1997, the annual number of referrals has steadily increased. In 2019, 513 domestic CSF specimens were referred for 14-3-3 protein testing and 85 persons with suspected human prion disease were formally added to the national register. As of 31 December 2019, just under half (42 cases) of the 85 suspect case notifications remain classified as ‘incomplete’; 16 cases were excluded through either detailed clinical follow-up (3 cases) or neuropathological examination (13 cases); 20 cases were classified as ‘definite’ and seven as ‘probable’ prion disease. For 2019, sixty-three percent of all suspected human prion disease related deaths in Australia underwent neuropathological examination. No cases of variant or iatrogenic CJD were identified. Two possibly causal novel prion protein gene (PRNP) sequence variations were identified. Keywords: Creutzfeldt-Jakob disease, prion disease, transmissible spongiform encephalopathy, disease surveillance


Sign in / Sign up

Export Citation Format

Share Document