Prion diseases are fatal neurodegenerative disorders connected with accumulation of aggregated misfolded prion protein in the brain of affected individuals. The diseases are transmissible, no therapy is available and at present the diagnosis is confirmed only after neuropathological assessment post mortem. Our project is aimed on utilization of a new revolutionary method, Real-Time Quaking Induced Conversion (RT-QuIC) assay, for intravital diagnostics of prion diseases. The method already showed superior sensitivity and specificity in analysis of cerebrospinal fluid which led to its recent inclusion into internationally recognized diagnostic criteria for Creutzfeldt-Jakob disease. Our project specifically aims to assess diagnostic potential of RT-QuIC in analysis of easily accessible samples of urine and skin. The importance of early diagnosis confirmation using minimally invasive procedure lays in mitigation of the risk of prion nosocomial transmission, in immediate implementation of special patient care and in securing a room for therapeutic intervention in the future.

Prionové choroby jsou smrtelná neurodegenerativní onemocnění spojená s hromaděním agregovaného konformačně pozměněného prionového proteinu v mozku postižených jedinců. Onemocnění je přenosné, neexistuje účinná léčba a v současnosti lze jeho diagnózu potvrdit pouze neuropatologickým vyšetřením post mortem. Náš projekt je zaměřen na využití nové revoluční metody RT-QuIC (Real-Time Quaking Induced Conversion) pro potvrzení diagnózy onemocnění za života pacienta. Metoda RT-QuIC již prokázala vysokou specificitu a senzitivitu při analýze mozkomíšního moku, která tento rok vedla k jejímu zahrnutí do mezinárodních diagnostických kritérií Cretzfeldtovy-Jakobovy nemoci. Náš projekt specificky cílí na posouzení diagnostického potenciálu RT-QuIC u snadno dostupných vzorků moči a kůže. Důležitost rychlého potvrzení diagnózy pomocí minimálně invazivního postupu tkví nejen v prevenci rizika nozokomiálního přenosu prionů a včasné aplikaci specializované péče o pacienta, ale i ve vytvoření nezbytného prostoru pro vyvíjené terapeutické zásahy v budoucnosti.

• Klíčová slova
• RT-QuIC,
• MeSH
• Creutzfeldtova-Jakobova nemoc diagnóza   MeSH
• klinické chemické testy metody   MeSH
• kůže chemie   MeSH
• moč chemie   MeSH
• mozkomíšní mok chemie   MeSH
• prionová bílkovina chemie   MeSH
• prionové nemoci diagnóza   MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• neurologie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Prion disorders, or transmissible spongiform encephalophaties (TSE), are fatal neurodegenerative diseases affecting mammals. Prion-infectious particles comprise of misfolded pathological prion proteins (PrPTSE). Different TSEs are associated with distinct PrPTSE folds called prion strains. The high resistance of prions to conventional sterilization increases the risk of prion transmission in medical, veterinary and food industry practices. Recently, we have demonstrated the ability of disulfonated hydroxyaluminum phthalocyanine to photodynamically inactivate mouse RML prions by generated singlet oxygen. Herein, we studied the efficiency of three phthalocyanine derivatives in photodynamic treatment of seven mouse adapted prion strains originating from sheep, human, and cow species. We report the different susceptibilities of the strains to photodynamic oxidative elimination of PrPTSE epitopes: RML, A139, Fu-1 > mBSE, mvCJD > ME7, 22L. The efficiency of the phthalocyanine derivatives in the epitope elimination also differed (AlPcOH(SO3)2 > ZnPc(SO3)1-3 > SiPc(OH)2(SO3)1-3) and was not correlated to the yields of generated singlet oxygen. Our data suggest that the structural properties of both the phthalocyanine and the PrPTSE strain may affect the effectiveness of the photodynamic prion inactivation. Our finding provides a new option for the discrimination of prion strains and highlights the necessity of utilizing range of prion strains when validating the photodynamic prion decontamination procedures.

• MeSH
• fotochemoterapie metody   MeSH
• fotosenzibilizující látky farmakologie   MeSH
• indoly chemie   MeSH
• lidé MeSH
• mozek účinky léků   metabolismus   účinky záření   MeSH
• myši MeSH
• organokovové sloučeniny chemie   MeSH
• ovce MeSH
• oxidace-redukce MeSH
• prionová bílkovina metabolismus   MeSH
• prionové nemoci farmakoterapie   metabolismus   patologie   MeSH
• sbalování proteinů MeSH
• singletový kyslík MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Gerstmann-Sträussler-Scheinker syndrome (GSS) is a hereditary neurodegenerative disease characterized by extracellular aggregations of pathological prion protein (PrP) forming characteristic plaques. Our study aimed to evaluate the micromorphology and protein composition of these plaques in relation to age, disease duration, and co-expression of other pathogenic proteins related to other neurodegenerations. Hippocampal regions of nine clinically, neuropathologically, and genetically confirmed GSS subjects were investigated using immunohistochemistry and multichannel confocal fluorescent microscopy. Most pathognomic prion protein plaques were small (2-10 μm), condensed, globous, and did not contain any of the other investigated proteinaceous components, particularly dystrophic neurites. Equally rare (in two cases out of nine) were plaques over 50 μm having predominantly fibrillar structure and exhibit the presence of dystrophic neuritic structures; in one case, the plaques also included bulbous dystrophic neurites. Co-expression with hyperphosphorylated protein tau protein or amyloid beta-peptide (Aβ) in GSS PrP plaques is generally a rare observation, even in cases with comorbid neuropathology. The dominant picture of the GSS brain is small, condensed plaques, often multicentric, while presence of dystrophic neuritic changes accumulating hyperphosphorylated protein tau or Aβ in the PrP plaques are rare and, thus, their presence probably constitutes a trivial observation without any relationship to GSS development and progression.

• MeSH
• dospělí MeSH
• Gerstmannova-Strausslerova-Scheinkerova nemoc * genetika   metabolismus   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• missense mutace * MeSH
• patologická konformace proteinů * genetika   metabolismus   patologie   MeSH
• prionová bílkovina * genetika   metabolismus   MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

Human prion disorders (transmissible spongiform encephalopathies, TSEs) are unique, progressive, and fatal neurodegenerative diseases caused by aggregation of misfolded prion protein in neuronal tissue. Due to the potential transmission, human TSEs are under active surveillance in a majority of countries; in the Czech Republic data are centralized at the National surveillance center (NRL) which has a clinical and a neuropathological subdivision. The aim of our article is to review current knowledge about human TSEs and summarize the experience of active surveillance of human prion diseases in the Czech Republic during the last 20 years. Possible or probable TSEs undergo a mandatory autopsy using a standardized protocol. From 2001 to 2020, 305 cases of sporadic and genetic TSEs including 8 rare cases of Gerstmann-Sträussler-Scheinker syndrome (GSS) were confirmed. Additionally, in the Czech Republic, brain samples from all corneal donors have been tested by the NRL immunology laboratory to increase the safety of corneal transplants since January 2007. All tested 6590 corneal donor brain tissue samples were negative for prion protein deposits. Moreover, the routine use of diagnostic criteria including biomarkers are robust enough, and not even the COVID-19 pandemic has negatively impacted TSEs surveillance in the Czech Republic.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Despite an early understanding of amyotrophic lateral sclerosis (ALS) as a disease affecting the motor system, including motoneurons in the motor cortex, brainstem, and spinal cord, today, many cases involving dementia and behavioral disorders are reported. Therefore, we currently divide ALS not only based on genetic predisposition into the most common sporadic variant (90% of cases) and the familial variant (10%), but also based on cognitive and/or behavioral symptoms, with five specific subgroups of clinical manifestation-ALS with cognitive impairment, ALS with behavioral impairment, ALS with combined cognitive and behavioral impairment, the fully developed behavioral variant of frontotemporal dementia in combination with ALS, and comorbid ALS and Alzheimer's disease (AD). Generally, these cases are referred to as amyotrophic lateral sclerosis-frontotemporal spectrum disorder (ALS-FTSD). Clinical behaviors and the presence of the same pathognomonic deposits suggest that FTLD and ALS could be a continuum of one entity. This review was designed primarily to compare neuropathological findings in different types of ALS relative to their characteristic locations as well as the immunoreactivity of the inclusions, and thus, foster a better understanding of the immunoreactivity, distribution, and morphology of the pathological deposits in relation to genetic mutations, which can be useful in specifying the final diagnosis.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The possibilities for diagnosing prion diseases have shifted significantly over the last 10 years. The RT-QuIC assay option has been added for neuropsychiatric symptoms, supporting biomarkers and final post-mortem confirmation. Samples of brain homogenates used for final diagnosis, archived for many years, provide the possibility for retrospective studies. We used a second-generation RT-QuIC assay to detect seeding activity in different types of sporadic and genetic prion diseases in archival brain homogenates and post-mortem CSF samples that were 2 to 15 years old. Together, we tested 92 archival brain homogenates: 39 with definite prion disease, 28 with definite other neurological disease, and 25 with no signs of neurological disorders. The sensitivity and specificity of the assay were 97.4% and 100%, respectively. Differences were observed in gCJD E200K, compared to the sporadic CJD group. In 52 post-mortem CSF samples-24 with definite prion disease and 28 controls-we detected the inhibition of seeding reaction due to high protein content. Diluting the samples eliminated such inhibition and led to 95.8% sensitivity and 100% specificity of the assay. In conclusion, we proved the reliability of archived brain homogenates and post-mortem CSF samples for retrospective analysis by RT-QuIC after long-term storage, without changed reactivity.

• Publikační typ
• časopisecké články MeSH

Neurodegenerative diseases are characterized by the deposition of specific protein aggregates, both intracellularly and/or extracellularly, depending on the type of disease. The extracellular occurrence of tridimensional structures formed by amyloidogenic proteins defines Alzheimer's disease, in which plaques are composed of amyloid β-protein, while in prionoses, the same term "amyloid" refers to the amyloid prion protein. In this review, we focused on providing a detailed didactic description and differentiation of diffuse, neuritic, and burnt-out plaques found in Alzheimer's disease and kuru-like, florid, multicentric, and neuritic plaques in human transmissible spongiform encephalopathies, followed by a systematic classification of the morphological similarities and differences between the extracellular amyloid deposits in these disorders. Both conditions are accompanied by the extracellular deposits that share certain signs, including neuritic degeneration, suggesting a particular role for amyloid protein toxicity.

• MeSH
• Alzheimerova nemoc metabolismus   MeSH
• amyloid metabolismus   MeSH
• amyloidní beta-protein metabolismus   MeSH
• amyloidní plaky metabolismus   MeSH
• amyloidogenní proteiny metabolismus   MeSH
• amyloidóza metabolismus   MeSH
• Creutzfeldtova-Jakobova nemoc metabolismus   MeSH
• lidé MeSH
• mozek metabolismus   patologie   MeSH
• neurity metabolismus   patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND INFORMATION: Cellular prion protein (PrPC ) is infamous for its role in prion diseases. The physiological function of PrPC remains enigmatic, but several studies point to its involvement in cell differentiation processes. To test this possibility, we monitored PrPC changes during the differentiation of prion-susceptible CAD 5 cells, and then we analysed the effect of PrPC ablation on the differentiation process. RESULTS: Neuronal CAD 5 cells differentiate within 5 days of serum withdrawal, with the majority of the cells developing long neurites. This process is accompanied by an up to sixfold increase in PrPC expression and enhanced N-terminal β-cleavage of the protein, which suggests a role for the PrPC in the differentiation process. Moreover, the majority of PrPC in differentiated cells is inside the cell, and a large proportion of the protein does not associate with membrane lipid rafts. In contrast, PrPC in proliferating cells is found mostly on the cytoplasmic membrane and is predominantly associated with lipid rafts. To determine the importance of PrPC in cell differentiation, a CAD 5 PrP-/- cell line with ablated PrPC expression was created using the CRISPR/Cas9 system. We observed no considerable difference in morphology, proliferation rate or expression of molecular markers between CAD 5 and CAD 5 PrP-/- cells during the differentiation initiated by serum withdrawal. CONCLUSIONS: PrPC characteristics, such as cell localisation, level of expression and posttranslational modifications, change during CAD 5 cell differentiation, but PrPC ablation does not change the course of the differentiation process. SIGNIFICANCE: Ablation of PrPC expression does not affect CAD 5 cell differentiation, although we observed many intriguing changes in PrPC features during the process. Our study does not support the concept that PrPC is important for neuronal cell differentiation, at least in simple in vitro conditions.

• MeSH
• buněčná diferenciace * MeSH
• buněčné linie MeSH
• membránové mikrodomény MeSH
• myši MeSH
• neurony cytologie   metabolismus   MeSH
• posttranslační úpravy proteinů MeSH
• priony metabolismus   MeSH
• PrPC proteiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Prion disorders are fatal neurodegenerative diseases caused by the autocatalytic conversion of a natively occurring prion protein (PrPC ) into its misfolded infectious form (PrPTSE ). The proven resistance of PrPTSE to common disinfection procedures increases the risk of prion transmission in medical settings. Herein, we present the effective photodynamic inactivation (PDI) of prions by disulfonated hydroxyaluminum phthalocyanine (AlPcOH(SO3 )2 ) utilizing two custom-built red light sources. The treatment eliminates PrPTSE signal in infectious mouse brain homogenate with efficiency that depends on light intensity but has a low effect on the overall protein content. Importantly, singlet oxygen (O2 (1 Δg )) is the only species significantly photogenerated by AlPcOH(SO3 )2 , and it is responsible for the PDI of prions. More intensive light conditions show not only higher O2 (1 Δg ) production but also decreases in AlPcOH(SO3 )2 photostability. Our findings suggest that PDI by AlPcOH(SO3 )2 -generated O2 (1 Δg ) represents a promising approach for prion inactivation that may be useful in future decontamination strategies for delicate medical tools.

• MeSH
• fotochemoterapie * MeSH
• fotosenzibilizující látky chemie   farmakologie   MeSH
• indoly chemie   farmakologie   MeSH
• kyseliny sulfonové chemie   MeSH
• mozek účinky léků   metabolismus   účinky záření   MeSH
• myši MeSH
• prionová bílkovina metabolismus   MeSH
• singletový kyslík metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH