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Przeglad Gastroenterologiczny 2015Keratins are proteins that form intermediate filaments of epithelial cell cytoskeleton. The utility of keratin expression determination is based on the fact that... (Review)
Review
Keratins are proteins that form intermediate filaments of epithelial cell cytoskeleton. The utility of keratin expression determination is based on the fact that epithelial cells acquire a specific pattern of keratin expression during differentiation and maturation, which reflects the specificity of the tissue and the degree of maturation, and generally remains stable during carcinogenesis. Determination of the pattern makes it possible to identify the origin of cells in diagnosing neoplastic lesions as well as in research on pathophysiology or the possibility to apply keratin-positive cell detection in the process of cancer staging and treatment planning. As keratins undergo degradation during apoptosis as caspase substrate the identification of the caspase-derived K18 fragment by the use of specific monoclonal antibody allows us to estimate the apoptosis/necrosis ratio, especially in liver pathology, e.g. nonalcoholic steatohepatitis, chronic hepatitis or graft-versus-host disease or in assessing response to antiviral or antitumour therapy.
PubMed: 26557935
DOI: 10.5114/pg.2015.51182 -
Journal of Neurology Sep 2021Neurofilament proteins have been extensively studied in relapsing-remitting multiple sclerosis, where they are promising biomarkers of disease activity and treatment... (Review)
Review
BACKGROUND
Neurofilament proteins have been extensively studied in relapsing-remitting multiple sclerosis, where they are promising biomarkers of disease activity and treatment response. Their role in progressive multiple sclerosis, where there is a particularly urgent need for improved biomarkers, is less clear. The objectives of this systematic review are to summarise the literature on neurofilament light and heavy in progressive multiple sclerosis, addressing key questions.
METHODS
A systematic search of PubMed, Embase, Web of Science and Scopus identified 355 potential sources. 76 relevant sources were qualitatively reviewed using QUADAS-2 criteria, and 17 were identified as at low risk of bias. We summarise the findings from all relevant sources, and separately from the 17 high-quality studies.
RESULTS
Differences in neurofilament light between relapsing-remitting and progressive multiple sclerosis appear to be explained by differences in covariates. Neurofilament light is consistently associated with current inflammatory activity and future brain atrophy in progressive multiple sclerosis, and is consistently shown to be a marker of treatment response with immunosuppressive disease-modifying therapies. Associations with current or future disability are inconsistent, and there is no evidence of NFL being a responsive marker of purportedly neuroprotective treatments. Evidence on neurofilament heavy is more limited and inconsistent.
CONCLUSIONS
Neurofilament light has shown consistent utility as a biomarker of neuroinflammation, future brain atrophy and immunosuppressive treatment response at a group level. Neither neurofilament light or heavy has shown a consistent treatment response to neuroprotective disease-modifying therapies, which will require further data from successful randomised controlled trials.
Topics: Biomarkers; Humans; Intermediate Filaments; Multiple Sclerosis; Multiple Sclerosis, Chronic Progressive; Multiple Sclerosis, Relapsing-Remitting; Neurofilament Proteins
PubMed: 32447549
DOI: 10.1007/s00415-020-09917-x -
Genes Apr 2024Neurofilament proteins have been implicated to be altered in amyotrophic lateral sclerosis (ALS). The objectives of this study were to assess the diagnostic and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Neurofilament proteins have been implicated to be altered in amyotrophic lateral sclerosis (ALS). The objectives of this study were to assess the diagnostic and prognostic utility of neurofilaments in ALS.
METHODS
Studies were conducted in electronic databases (PubMed/MEDLINE, Embase, Web of Science, and Cochrane CENTRAL) from inception to 17 August 2023, and investigated neurofilament light (NfL) or phosphorylated neurofilament heavy chain (pNfH) in ALS. The study design, enrolment criteria, neurofilament concentrations, test accuracy, relationship between neurofilaments in cerebrospinal fluid (CSF) and blood, and clinical outcome were recorded. The protocol was registered with PROSPERO, CRD42022376939.
RESULTS
Sixty studies with 8801 participants were included. Both NfL and pNfH measured in CSF showed high sensitivity and specificity in distinguishing ALS from disease mimics. Both NfL and pNfH measured in CSF correlated with their corresponding levels in blood (plasma or serum); however, there were stronger correlations between CSF NfL and blood NfL. NfL measured in blood exhibited high sensitivity and specificity in distinguishing ALS from controls. Both higher levels of NfL and pNfH either measured in blood or CSF were correlated with more severe symptoms as assessed by the ALS Functional Rating Scale Revised score and with a faster disease progression rate; however, only blood NfL levels were associated with shorter survival.
DISCUSSION
Both NfL and pNfH measured in CSF or blood show high diagnostic utility and association with ALS functional scores and disease progression, while CSF NfL correlates strongly with blood (either plasma or serum) and is also associated with survival, supporting its use in clinical diagnostics and prognosis. Future work must be conducted in a prospective manner with standardized bio-specimen collection methods and analytical platforms, further improvement in immunoassays for quantification of pNfH in blood, and the identification of cut-offs across the ALS spectrum and controls.
Topics: Amyotrophic Lateral Sclerosis; Humans; Neurofilament Proteins; Biomarkers; Intermediate Filaments; Prognosis
PubMed: 38674431
DOI: 10.3390/genes15040496 -
BMJ (Clinical Research Ed.) Jul 2009To investigate whether filaggrin gene defects, present in up to one in 10 western Europeans and North Americans, increase the risk of developing allergic sensitisation... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To investigate whether filaggrin gene defects, present in up to one in 10 western Europeans and North Americans, increase the risk of developing allergic sensitisation and allergic disorders.
DESIGN
Systematic review and meta-analysis.
DATA SOURCES
Medline, Embase, ISI Science Citation Index, BIOSIS, ISI Web of Knowledge, UK National Research Register, clinical trials.gov, the Index to Theses and Digital dissertations, and grey literature using OpenSIGLE.
STUDY SELECTION
Genetic epidemiological studies (family, case-control) of the association between filaggrin gene defects and allergic sensitisation or allergic disorders.
DATA EXTRACTION
Atopic eczema or dermatitis, food allergy, asthma, allergic rhinitis, and anaphylaxis, along with relevant immunological variables relating to the risk of allergic sensitisation as assessed by either positive skin prick testing or increased levels of allergen specific IgE.
DATA SYNTHESIS
24 studies were included. The odds of developing allergic sensitisation was 1.91 (95% confidence interval 1.44 to 2.54) in the family studies and 1.57 (1.20 to 2.07) in the case-control studies. The odds of developing atopic eczema was 1.99 (1.72 to 2.31) in the family studies and 4.78 (3.31 to 6.92) in the case-control studies. Three studies investigated the association between filaggrin gene mutations and allergic rhinitis in people without atopic eczema: overall odds ratio 1.78 (1.16 to 2.73). The four studies that investigated the association between filaggrin gene mutations and allergic rhinitis in people with atopic eczema reported a significant association: pooled odds ratio from case-control studies 2.84 (2.08 to 3.88). An overall odds ratio for the association between filaggrin gene mutations and asthma in people with atopic eczema was 2.79 (1.77 to 4.41) in case-control studies and 2.30 (1.66 to 3.18) in family studies. None of the studies that investigated filaggrin gene mutations and asthma in people without atopic eczema reported a significant association; overall odds ratio was 1.30 (0.7 to 2.30) in the case-control studies. The funnel plots suggested that publication bias was unlikely to be an explanation for these findings. No studies investigated the association between filaggrin gene mutations and food allergy or anaphylaxis.
CONCLUSIONS
Filaggrin gene defects increase the risk of developing allergic sensitisation, atopic eczema, and allergic rhinitis. Evidence of the relation between filaggrin gene mutations and atopic eczema was strong, with people manifesting increased severity and persistence of disease. Filaggrin gene mutations also increased the risk of asthma in people with atopic eczema. Restoring skin barrier function in filaggrin deficient people in early life may help prevent the development of sensitisation and halt the development and progression of allergic disease.
Topics: Epidemiologic Methods; Filaggrin Proteins; Humans; Hypersensitivity; Intermediate Filament Proteins; Mutation; Pedigree; Risk Factors
PubMed: 19589816
DOI: 10.1136/bmj.b2433 -
Glia Aug 2021Astrocytes regulate synaptic communication and are essential for proper brain functioning. In Alzheimer's disease (AD) astrocytes become reactive, which is characterized... (Review)
Review
Astrocytes regulate synaptic communication and are essential for proper brain functioning. In Alzheimer's disease (AD) astrocytes become reactive, which is characterized by an increased expression of intermediate filament proteins and cellular hypertrophy. Reactive astrocytes are found in close association with amyloid-beta (Aβ) deposits. Synaptic communication and neuronal network function could be directly modulated by reactive astrocytes, potentially contributing to cognitive decline in AD. In this review, we focus on reactive astrocytes as treatment targets in AD in the APPswePS1dE9 AD mouse model, a widely used model to study amyloidosis and gliosis. We first give an overview of the model; that is, how it was generated, which cells express the transgenes, and the effect of its genetic background on Aβ pathology. Subsequently, to determine whether modifying reactive astrocytes in AD could influence pathogenesis and cognition, we review studies using this mouse model in which interventions were directly targeted at reactive astrocytes or had an indirect effect on reactive astrocytes. Overall, studies specifically targeting astrocytes to reduce astrogliosis showed beneficial effects on cognition, which indicates that targeting astrocytes should be included in developing novel therapies for AD.
Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Astrocytes; Disease Models, Animal; Gliosis; Mice; Mice, Transgenic
PubMed: 33634529
DOI: 10.1002/glia.23981 -
International Journal of Molecular... Mar 2024Peripheral and autonomic neuropathy are common disease manifestations in systemic amyloidosis. The neurofilament light chain (NfL), a neuron-specific biomarker, is... (Review)
Review
Peripheral and autonomic neuropathy are common disease manifestations in systemic amyloidosis. The neurofilament light chain (NfL), a neuron-specific biomarker, is released into the blood and cerebrospinal fluid after neuronal damage. There is a need for an early and sensitive blood biomarker for polyneuropathy, and this systematic review provides an overview on the value of NfL in the early detection of neuropathy, central nervous system involvement, the monitoring of neuropathy progression, and treatment effects in systemic amyloidosis. A literature search in PubMed, Embase, and Web of Science was performed on 14 February 2024 for studies investigating NfL levels in patients with systemic amyloidosis and transthyretin gene-variant (v) carriers. Only studies containing original data were included. Included were thirteen full-text articles and five abstracts describing 1604 participants: 298 controls and 1306 v carriers or patients with or without polyneuropathy. Patients with polyneuropathy demonstrated higher NfL levels compared to healthy controls and asymptomatic carriers. Disease onset was marked by rising NfL levels. Following the initiation of transthyretin gene-silencer treatment, NfL levels decreased and remained stable over an extended period. NfL is not an outcome biomarker, but an early and sensitive disease-process biomarker for neuropathy in systemic amyloidosis. Therefore, NfL has the potential to be used for the early detection of neuropathy, monitoring treatment effects, and monitoring disease progression in patients with systemic amyloidosis.
Topics: Humans; Prealbumin; Intermediate Filaments; Immunoglobulin Light-chain Amyloidosis; Amyloidosis; Polyneuropathies; Biomarkers
PubMed: 38612579
DOI: 10.3390/ijms25073770 -
Journal of Integrative Neuroscience Jun 2023Plasma neurofilament light (NfL) is an intermediate filamentous protein involved in stabilizing axonal structure and promoting axon growth. Recent clinical studies have... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Plasma neurofilament light (NfL) is an intermediate filamentous protein involved in stabilizing axonal structure and promoting axon growth. Recent clinical studies have reported increased NfL levels in the plasma of Alzheimer's disease (AD) patients and patients with mild cognitive impairment (MCI). This study used meta-analysis to evaluate the potential of plasma NfL as a biomarker for patients with AD and MCI.
METHODS
PubMed, Embase, and Web of Science databases were systematically searched for studies of plasma NfL levels in AD and MCI, and a meta-analysis was employed to identify whether it was suited as a reliable biomarker and discrimination of healthy controls.
RESULTS
A total of 24 published articles that included 2397 AD and 3242 MCI patients were analysed. The level of plasma NfL was significantly increased in patients with AD and MCI when compared with healthy control subjects (standard mean difference [SMD]: 14.33 [12.42-16.24], z = 14.71, < 0.00001; SMD: 4.95 [3.82-6.80], z = 8.59, < 0.00001) and higher in AD patients than MCI patients (SMD: 9.32 [8.07-10.57], z = 14.62, < 0.00001). Meta-regression analysis showed a negative relationship between Mini-Mental State Examination (MMSE) scores and plasma NfL levels in MCI patients (slope = -0.399 [95% confidence interval (CI): -0.518 to -0.281], < 0.05).
CONCLUSIONS
The meta-analysis suggested that NfL levels increased in the plasma of patients with AD and MCI and were associated with cognitive decline. Results provide the clinical evidence to support plasma NfL as a cognitive biomarker for AD and MCI.
Topics: Humans; Alzheimer Disease; Intermediate Filaments; Cognitive Dysfunction; Biomarkers
PubMed: 37519166
DOI: 10.31083/j.jin2204085 -
PloS One 2022Neurofilament light chain (NfL) in cerebrospinal fluid (CSF) is a biomarker of multiple sclerosis (MS). However, CSF sampling is invasive and has limited the clinical... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Neurofilament light chain (NfL) in cerebrospinal fluid (CSF) is a biomarker of multiple sclerosis (MS). However, CSF sampling is invasive and has limited the clinical application. With the development of highly sensitive single-molecule assay, the accurate quantification of the very low NfL levels in blood become feasible. As evidence being accumulated, we performed a meta-analysis to evaluate the diagnostic and predictive value of blood NfL in MS patients.
METHODS
We performed literature search on PubMed, EMBASE, Web of Science and Cochrane Library from inception to May 31, 2022. The blood NfL differences between MS vs. controls, MS vs. clinically isolated syndrome (CIS), progressive MS (PMS) vs. relapsing-remitting MS (RRMS), and MS in relapse vs. MS in remission were estimated by standard mean difference (SMD) and corresponding 95% confidence interval (CI). Pooled hazard ratio (HR) and 95%CI were calculated to predict time to reach Expanded Disability Status Scale (EDSS) score≥4.0 and to relapse.
RESULTS
A total of 28 studies comprising 6545 MS patients and 2477 controls were eligible for meta-analysis of diagnosis value, and 5 studies with 4444 patients were synthesized in analysis of predictive value. Blood NfL levels were significantly higher in MS patients vs. age-matched controls (SMD = 0.64, 95%CI 0.44-0.85, P<0.001), vs. non-matched controls (SMD = 0.76, 95%CI 0.56-0.96, P<0.001) and vs. CIS patients (SMD = 0.30, 95%CI 0.18-0.42, P<0.001), in PMS vs. RRMS (SMD = 0.56, 95%CI 0.27-0.85, P<0.001), and in relapsed patients vs. remitted patients (SMD = 0.54, 95%CI 0.16-0.92, P = 0.005). Patients with high blood NfL levels had shorter time to reach EDSS score≥4.0 (HR = 2.36, 95%CI 1.32-4.21, P = 0.004) but similar time to relapse (HR = 1.32, 95%CI 0.90-1.93, P = 0.155) compared to those with low NfL levels.
CONCLUSION
As far as we know, this is the first meta-analysis evaluating the diagnosis and predictive value of blood NfL in MS. The present study indicates blood NfL may be a useful biomarker in diagnosing MS, distinguishing MS subtypes and predicting disease worsening in the future.
Topics: Biomarkers; Humans; Intermediate Filaments; Multiple Sclerosis; Multiple Sclerosis, Chronic Progressive; Recurrence
PubMed: 36103562
DOI: 10.1371/journal.pone.0274565 -
International Journal of Molecular... Oct 2023Coronavirus disease 2019 (COVID-19) has been linked to various neurological complications. This meta-analysis assessed the relationship between glial fibrillary acidic... (Meta-Analysis)
Meta-Analysis Review
Coronavirus disease 2019 (COVID-19) has been linked to various neurological complications. This meta-analysis assessed the relationship between glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) levels in the blood and neurological injury in COVID-19 patients. A comprehensive search of various databases was conducted until 18 August 2023, to find studies reporting GFAP and NfL blood levels in COVID-19 patients with neurological complications. GFAP and NfL levels were estimated between COVID-19 patients and healthy controls, and meta-analyses were performed using RevMan 5.4 software for analysis. In the 21 collected studies, it was found that COVID-19 patients had significantly higher levels of pooled GFAP (SMD = 0.52; 95% CI: 0.31, 0.73; ≤ 0.001) and NfL (SMD = 0.60; 95% CI: 0.37, 0.82; ≤ 0.001) when compared to the healthy controls. The pooled GFAP (SMD = 0.86; 95% CI: 0.26, 1.45; ≤ 0.01) and NfL (SMD = 0.87; 95% CI: 0.48, 1.26; ≤ 0.001) were significantly higher in non-survivors. These findings indicate a significant association between COVID-19 severity and elevated levels of GFAP and NfL, suggesting that GFAP and NfL could serve as potential diagnostic and prognostic markers for the early detection and monitoring of COVID-19-related neurological injuries.
Topics: Humans; Prognosis; COVID-19; Biomarkers; Glial Fibrillary Acidic Protein; Neurofilament Proteins; Intermediate Filaments
PubMed: 37958721
DOI: 10.3390/ijms242115738 -
Glia Aug 2019Gliomas are a heterogenous group of malignant primary brain tumors that arise from glia cells or their progenitors and rely on accurate diagnosis for prognosis and...
Gliomas are a heterogenous group of malignant primary brain tumors that arise from glia cells or their progenitors and rely on accurate diagnosis for prognosis and treatment strategies. Although recent developments in the molecular biology of glioma have improved diagnosis, classical histological methods and biomarkers are still being used. The glial fibrillary acidic protein (GFAP) is a classical marker of astrocytoma, both in clinical and experimental settings. GFAP is used to determine glial differentiation, which is associated with a less malignant tumor. However, since GFAP is not only expressed by mature astrocytes but also by radial glia during development and neural stem cells in the adult brain, we hypothesized that GFAP expression in astrocytoma might not be a direct indication of glial differentiation and a less malignant phenotype. Therefore, we here review all existing literature from 1972 up to 2018 on GFAP expression in astrocytoma patient material to revisit GFAP as a marker of lower grade, more differentiated astrocytoma. We conclude that GFAP is heterogeneously expressed in astrocytoma, which most likely masks a consistent correlation of GFAP expression to astrocytoma malignancy grade. The GFAP positive cell population contains cells with differences in morphology, function, and differentiation state showing that GFAP is not merely a marker of less malignant and more differentiated astrocytoma. We suggest that discriminating between the GFAP isoforms GFAPδ and GFAPα will improve the accuracy of assessing the differentiation state of astrocytoma in clinical and experimental settings and will benefit glioma classification.
Topics: Animals; Astrocytoma; Biomarkers, Tumor; Central Nervous System Neoplasms; Glial Fibrillary Acidic Protein; Humans; Protein Isoforms
PubMed: 30667110
DOI: 10.1002/glia.23594