Tau protein je jedním z neurocytoskeletálních proteinů podílejících se na patogenezi závažných neurologických onemocnění, zejména Alzheimerovy nemoci. Vyznačuje se značnou strukturní variabilitou, která se odráží v existenci jeho četných proteoforem. Tento přehled si klade za cíl poskytnout stručné informace o struktuře tau proteinu a jeho proteoformách, které se zdají být perspektivní jako biomarkery pro klinické použití. Jsou diskutovány biologické tekutiny vhodné pro laboratorní vyšetření v klinické praxi, tj. mozkomíšní mok a krev (plazma/sérum). Celkový tau protein a jeho fosforylované formy (hlavně protein pT181-tau, fosforylovaný na threoninovém zbytku 181) již našly klinické uplatnění v diagnostice Alzheimerovy nemoci.
The tau protein is one of the neurocytoskeletal proteins that participate in the pathogenesis of serious neurological diseases, especially Alzheimer's disease. The tau protein is characterized by considerable structural variability, which is reflected in the existence of its numerous proteoforms. This review aims to provide brief information on the structure of tau protein and its proteoforms, which seem promising biomarkers for clinical use. Biological fluids, suitable for laboratory examination in clinical practice, i.e., cerebrospinal fluid and blood (plasma/serum), are discussed. Total tau protein and its phosphorylated forms (mainly the pT181-tau protein, phosphorylated at the threonine residue 181) have already found clinical application in diagnosis of Alzheimer's disease.
- Publikační typ
- abstrakt z konference MeSH
In this prospective longitudinal study, we quantified regional brain volume and susceptibility changes during the first two years after the diagnosis of multiple sclerosis (MS) and identified their association with cerebrospinal fluid (CSF) markers at baseline. Seventy patients underwent MRI (T1 and susceptibility weighted images processed to quantitative susceptibility maps, QSM) with neurological examination at the diagnosis and after two years. In CSF obtained at baseline, the levels of oxidative stress, products of lipid peroxidation, and neurofilaments light chain (NfL) were determined. Brain volumetry and QSM were compared with a group of 58 healthy controls. In MS patients, regional atrophy was identified in the striatum, thalamus, and substantia nigra. Magnetic susceptibility increased in the striatum, globus pallidus, and dentate and decreased in the thalamus. Compared to controls, MS patients developed greater atrophy of the thalamus, and a greater increase in susceptibility in the caudate, putamen, globus pallidus and a decrease in the thalamus. Of the multiple calculated correlations, only the decrease in brain parenchymal fraction, total white matter, and thalamic volume in MS patients negatively correlated with increased NfL in CSF. Additionally, negative correlation was found between QSM value in the substantia nigra and peroxiredoxin-2, and QSM value in the dentate and lipid peroxidation levels.
- MeSH
- atrofie patologie MeSH
- lidé MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie metody MeSH
- mozek diagnostické zobrazování patologie MeSH
- nemoci centrálního nervového systému * patologie MeSH
- oxidační stres MeSH
- prospektivní studie MeSH
- roztroušená skleróza * diagnostické zobrazování patologie MeSH
- šedá hmota patologie MeSH
- železo MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
AIMS: Antiphosphatidylethanolamine antibodies (aPE) represent one type of antiphospholipid antibody (aPL) directed against the neutral phospholipids - phosphatidylethanolamines. The aim of this study was to evaluate levels and avidities of aPE in several groups of patients and compare them with conventional aPLs. METHODS: aPE were analysed in a cohort consisting of 68 hospitalized patients. The other cohort comprised 22 patients with immunologically-mediated diseases. The control group consisted of 20 healthy persons. ELISA methods were used for determination of aPL. Avidities of aPE were tested by modified ELISA with urea as a chaotropic agent. RESULTS: aPE IgG/IgM were significantly higher in the group of patients with venous thromboembolism than those with non-thrombotic internal disorders (P=0.02 for both Ig classes). aPE IgG/IgM elevated above cut-off values were found in 10.8% of patients with venous thromboembolism and as a single aPL in 6.5%. Levels of aPE IgG higher than our limit (>6 U/mL) were detected in 29% of patients with immunologically-mediated diseases with other positive aPL. Low-, intermediate- and high-avidity aPE IgG were found in patients of both cohorts. The avidities of aPE IgG differed from those of anticardiolipin antibodies IgG. Neither aPE IgG levels nor avidity dynamics significantly changed during follow-up. CONCLUSION: aPE may be related to venous thromboembolism and may be part of the repertoire of aPL in immunologically-mediated diseases. There are patients with thrombosis negative for conventional aPL but positive for aPE. aPE IgG may have different avidities.
- MeSH
- Hominidae * MeSH
- imunoglobulin G MeSH
- imunoglobulin M analýza MeSH
- lidé MeSH
- systémový lupus erythematodes * MeSH
- trombóza * MeSH
- žilní tromboembolie * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Early diagnosis and treatment of patients with multiple sclerosis (MS) are associated with better outcomes; however, diagnostic delays remain a major problem. OBJECTIVE: Describe the prevalence, determinants and consequences of delayed diagnoses. METHODS: This single-centre ambispective study analysed 146 adult relapsing-remitting MS patients (2016-2021) for frequency and determinants of diagnostic delays and their associations with clinical, cognitive, imaging and biochemical measures. RESULTS: Diagnostic delays were identified in 77 patients (52.7%), including 42 (28.7%) physician-dependent cases and 35 (24.0%) patient-dependent cases. Diagnosis was delayed in 22 (15.1%) patients because of misdiagnosis by a neurologist. A longer diagnostic delay was associated with trends towards greater Expanded Disability Status Scale (EDSS) scores (B = 0.03; p = 0.034) and greater z-score of the blood neurofilament light chain (B = 0.35; p = 0.031) at the time of diagnosis. Compared with patients diagnosed at their first clinical relapse, patients with a history of >1 relapse at diagnosis (n = 63; 43.2%) had a trend towards greater EDSS scores (B = 0.06; p = 0.006) and number of total (B = 0.13; p = 0.040) and periventricular (B = 0.06; p = 0.039) brain lesions. CONCLUSION: Diagnostic delays in MS are common, often determined by early misdiagnosis and associated with greater disease burden.
- MeSH
- dospělí MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mozek patologie MeSH
- opožděná diagnóza MeSH
- prevalence MeSH
- recidiva MeSH
- relabující-remitující roztroušená skleróza * diagnóza epidemiologie patologie MeSH
- roztroušená skleróza * diagnóza epidemiologie patologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Tento přehled si klade za cíl seznámit klinické a laboratorní pracovníky s nejdůležitějšími preanalytickými a analytickými aspekty stanovení lehkých řetězců neurofilament (NfL) v biologických tekutinách. NfL představují perspektivní nespecifický biomarker poškození neuronů a axonů, k němuž dochází u celé řady neurologických onemocnění. Před zavedením vyšetřování NfL do širší klinické praxe je nutné charakterizovat preanalytické a analytické stránky stanovení, které mohou významným způsobem ovlivnit správnost výsledku analýzy. Při hodnocení koncentrací NfL je zapotřebí brát v úvahu věk pacienta a vliv může mít i body mass index. Výhodou NfL je jejich dlouhodobá stabilita při různých teplotách skladování i odolnost vůči opakovaným cyklům zmrazování a rozmrazování. Koncentrace NfL v klinických studiích se stanovují především imunoanalytickými metodami, které se liší citlivostí. Pro stanovení NfL existuje několik imunoanalytických přístupů vhodných pro spolehlivé vyšetření v mozkomíšním moku (MMM) i v séru/plazmě. Volba optimálního analytického přístupu závisí mimo jiné na koncentracích NfL v biologických tekutinách. Pro stanovení NfL v MMM lze využít metod ELISA, které vykazují dostačující citlivost pro vyšší koncentrace NfL vyskytující se v této biologické tekutině. Postupně zaváděné nové technologie charakterizované výrazně vyšší citlivostí ve srovnání s metodou ELISA umožnily spolehlivé vyšetřování NfL i v séru či plazmě. Podrobněji jsou zmiňovány principy metod postavené na technologii Simoa®, SimplePlexTM a imunomagnetické redukce.
The aim of this review is to inform clinical and laboratory workers about the most important pre-analytical and analytical aspects of neurofilament light chain (NfL) determination in biological fluids. NfLs represent a promising nonspecific biomarker of neuronal and axonal damage that occurs in a variety of neurological diseases. Before introducing NfL determination into routine clinical practice, it is necessary to characterize the pre-analytical and analytical aspects of the assays, which can significantly affect the accuracy of the analysis results. When evaluating NfL concentrations, the patient‘s age should be taken into account and body mass index may also have an effect. The advantages of NfLs are their long-term storage stability at different temperatures as well as resistance to repeated freezing and thawing cycles. NfL concentrations in clinical trials are determined primarily by immunoassay methods that vary in sensitivity. There are several immunoassay technologies for the determination of NfL suitable for reliable determination in cerebrospinal fluid (CSF) and serum/plasma. The choice of the optimal analytical approach depends, among other things, on the concentration of NfL in biological fluids. ELISA methods can be used to determine NfL in CSF, which show sufficient sensitivity for higher concentrations of NfL occurring in this biological fluid. Newly introduced technologies characterized by significantly higher sensitivity in comparison with the ELISA methods enabled reliable examination of NfL also in serum/plasma. The principles of methods based on Simoa® technology, SimplePlexTM, and immunomagnetic reduction are mentioned in more detail.
- MeSH
- biologické markery analýza chemie MeSH
- intermediární filamenta * chemie MeSH
- lidé MeSH
- mozkomíšní mok chemie MeSH
- preanalytická fáze metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
BACKGROUND: Serum neurofilament light chain (sNfL) is a marker of neuroaxonal injury. There is a lack of studies investigating the dynamics of relationships between sNfL levels and radiological disease activity over long-term follow-up in multiple sclerosis (MS). OBJECTIVES: To investigate the relationship among repeated measures of sNfL, lesion burden accumulation, brain volume loss and clinical measures. METHODS: We investigated 172 patients in the early stages of MS (McDonald 2017 criteria). Clinical exams were performed every 3 months and brain magnetic resonance imaging (MRI) scans were collected annually over 48 months. sNfL levels were measured in serum by Simoa assay at the time of treatment initiation and then annually over 36 months. RESULTS: In repeated-measures analysis, considering all time points, we found a strong relationship between percentage changes of sNfL and lesion burden accumulation assessed by T1 lesion volume (p < 0.001) and T2 lesion number (p < 0.001). There was no relationship between percentage changes of sNfL and brain volume loss over 36 months (p > 0.1). Early sNfL levels were associated with delayed brain volume loss after 48 months (p < 0.001). Patients with No Evidence of Disease Activity (NEDA-3) status showed lower sNfL levels compared with active MS patients. CONCLUSIONS: sNfL is associated with ongoing neuroinflammation and predictive of future neurodegeneration in early MS.
- MeSH
- biologické markery MeSH
- intermediární filamenta MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mozek diagnostické zobrazování MeSH
- neurofilamentové proteiny MeSH
- roztroušená skleróza * diagnostické zobrazování MeSH
- zánět diagnostické zobrazování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Neurofilament light chain level in serum (sNfL) and cerebrospinal fluid (CSF-NfL) is a promising biomarker of disease activity in multiple sclerosis (MS). However, predictive value of neurofilaments for development of cognitive decline over long-term follow-up has not been extensively studied. OBJECTIVE: To investigate the relationship between early neurofilament levels and cognitive performance after 9-years. METHODS: We included 58 MS patients from the SET study. sNfL levels were measured at screening, at 1 and 2 years. CSF-NfL were measured in 36 patients at screening. Cognitive performance was assessed by the Brief International Cognitive Assessment for Multiple Sclerosis and the Paced Auditory Serial Addition Test-3 s at baseline, at 1, 2 and 9 years. Association between neurofilament levels and cognition was analyzed using Spearman ́s correlation, logistic regression and mixed models. RESULTS: We did not observe associations among early sNfL levels and cross-sectional or longitudinal cognitive measures, except of a trend for association between higher sNfL levels at screening and lower California Verbal Learning Test-II (CVLT-II) scores at year 1 (rho=-0.31, unadjusted p = 0.028). Higher sNfL level was not associated with increased risk of cognitive decline, except of a trend for greater risk of CVLT-II decrease in patients with higher sNfL levels at 1 year (OR=15.8; 95% CI=1.7-147.0; unadjusted p = 0.015). Similar trends were observed for CSF-NfL. CONCLUSION: We found only weak association between sNfL levels at disease onset and evolution of cognitive performance over long-term follow-up.
- MeSH
- biologické markery MeSH
- intermediární filamenta * MeSH
- kognice MeSH
- lidé MeSH
- neurofilamentové proteiny MeSH
- průřezové studie MeSH
- roztroušená skleróza * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: The role of cholesterol homeostasis in neuroaxonal injury in multiple sclerosis is not known. OBJECTIVE: The objective of the study is to investigate the associations of cerebrospinal fluid (CSF) and serum neurofilament light chain levels (CSF-NfL and sNfL, respectively), which are biomarkers of neuroaxonal injury, with cholesterol biomarkers at the clinical onset of multiple sclerosis. METHODS: sNfL, serum cholesterol profile (total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), serum apolipoprotein (Apo) levels (ApoA-I, ApoA-II, ApoB, and ApoE), and albumin quotient were obtained for 133 patients (63% female, age: 29.9 ± 8.0 years) during the first demyelinating event. CSF-NfL was available for 103 (77%) patients. RESULTS: CSF-NfL and sNfL were negatively associated with serum ApoA-II (P = .005, P < .001) and positively associated with albumin quotient (P < .001, P < .0001). In addition, higher CSF-NfL was associated with lower serum ApoA-I (P = .009) levels and higher sNfL was associated with lower high-density lipoprotein cholesterol (P = .010). In stepwise regression, age (P = .045), serum ApoA-II (P = .022), and albumin quotient (P < .001) were associated with CSF-NfL; albumin quotient (P = .002) and ApoA-II (P = .001) were associated with sNfL. Path analysis identified parallel pathways from ApoA-II (P = .009) and albumin quotient (P < .001) to the sNfL outcome that were mediated by CSF-NfL (P < .001). The associations of CSF-NfL with ApoA-I (P = .014) and ApoA-II (P = .015) and sNfL with ApoA-II (P < .001) remained significant after adjusting for number of contrast-enhancing lesions and T2 lesion volume. CONCLUSION: Lower serum ApoA-II and ApoA-I levels are associated with greater neuroaxonal injury as measured by CSF-NfL.
- MeSH
- apolipoprotein A-I krev MeSH
- apolipoprotein A-II krev MeSH
- dospělí MeSH
- lidé MeSH
- longitudinální studie MeSH
- neurofilamentové proteiny mozkomíšní mok MeSH
- neuroprotektivní látky krev mozkomíšní mok MeSH
- prognóza MeSH
- prospektivní studie MeSH
- roztroušená skleróza krev mozkomíšní mok patologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cíl: Cílem práce bylo porovnat metody ELISA pro stanovení hladin tripletu proteinů – celkového (t-tau) a fosforylovaného tau (p-tau) proteinů a β-amyloidu (1– 42) (Aβ42) v mozkomíšním moku (MMM) od dvou výrobců Fujirebio a EUROIMMUN a zároveň vytvořit orientační vodítka pro normální koncentrace u české populace od kognitivně zdravých starších osob. Soubor a metodika: Koncentrace likvorového tripletu proteinů od 38 kognitivně zdravých osob starších 55 let (19 mužů, průměrný věk 67 ± 8 let) byly změřeny jak soupravami ELISA INNOTEST, tak soupravami EUROIMMUN AG. Výsledky: Výsledky srovnání metod pro t-tau a p-tau proteiny a Aβ42 pomocí rozdílového grafu dle Blanda a Altmana ukazují, že hodnoty rozdílů mezi metodami ležely v rozsahu limitů shody (průměr ± 1,96 SD) až na ojedinělé výjimky odlehlých hodnot. Hodnoty korelačních koeficientů svědčí pro významnou shodu pro soupravy na stanovení t-tau proteinu. Na základě našich výsledků a zkušeností navrhujeme rozdělit koncentrace likvorového tripletu na tři skupiny: 1. snížené; 2. nerozhodné a hraniční; 3. zvýšené koncentrace v ng/ l na základě našeho konsenzu takto: t-tau protein < 280– 400 >, p181-tau protein < 50– 60 > a Aβ42 < 430– 480 >. Závěr: Soupravy ELISA obou výrobců jsou vhodné ke stanovení tripletu proteinů v MMM. Pro jejich referenční rozmezí lze orientačně využít naše výsledky, založené na reálném měření vzorků pečlivě vybraných a vyšetřených zdravých starších osob z ČR, nebo normy na základě našeho společného názoru.
Aim: The aim of the study was to compare ELISA methods for determination of triplet protein levels – total (t-tau) and phosphorylated tau (p-tau) proteins and β-amyloid (1– 42) (Aβ42) in cerebrospinal fl uid (CSF) from manufacturers Fujirebio and EUROIMMUN; and to provide guidance for normal concentrations from cognitively healthy elderly people. Patients and methods: The group consisted of 38 cognitively healthy persons over 55 years of age (19 men) whose average age was 67 ± 8 years. In each CSF sample, we examined the protein triplet by both ELISA INNOTEST and EUROIMMUN AG kits. Results: A comparison of ELISA methods for determination of t-tau and p-tau proteins and Aβ42 us ing the Bland and Altman difference graph shows that the differences between methods, with the exception of isolated outliers, were within the range of compliance (mean ± 1.96 SD). Cor relation coeffi cient values suggest significant agreement for t-tau protein as say kits. Based on our results and experience, we propose to clas sify CSF concentrations into three groups: 1. decreased; 2. questionable and borderline; 3. increased concentrations in ng/ L based on our consensus as follows: t-tau protein < 280– 400 >, p181-tau protein < 50– 60 > and Aβ42 < 430– 480 >. Conclusion: ELISA kits from two producers are suitable for determination of the triplet proteins in CSF. Our results based on real measurements of samples of carefully selected and examined healthy elderly people from the Czech Republic or the norms based on our consensus recom mendation can be used as reference range of the triplet.
- MeSH
- Alzheimerova nemoc * diagnóza MeSH
- amyloidní beta-protein * analýza MeSH
- ELISA MeSH
- klinická studie jako téma MeSH
- lidé středního věku MeSH
- lidé MeSH
- mozkomíšní mok MeSH
- proteiny tau analýza MeSH
- proteiny v mozkomíšním moku * analýza MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
