Neurofilament Light Chain as a Biomarker in Multiple Sclerosis

Neurofilament light chain as a biomarker of chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of chemotherapy. The frequency of CIPN ranges from one in three to almost all patients depending on type of chemotherapy and dose. It causes symptoms that can range from sensitivity to touch and numbness to neuropathic pain in hands and feet. CIPN is notoriously difficult to grade objectively and has mostly relied on a clinician- or patient-based rating that is subjective and poorly reproducible. Thus, considerable effort has been aimed at identifying objective biomarkers of CIPN. Recent in vitro, animal, and clinical studies suggest that neurofilament light chain (NFL), a structural neuronal protein, may be an objective biomarker of CIPN. NFL released from cells to cell culture media reflects in vitro neurotoxicity, while NFL in serum reflects neuronal damage caused by chemotherapy in rodent models. Finally, NFL in serum may be a diagnostic biomarker of CIPN, but its prognostic ability to predict CIPN requires prospective evaluation. We discuss current limitations and future perspectives on the use of NFL as a preclinical and clinical biomarker of CIPN.

Glymphatic dysfunction in multiple sclerosis and its association with disease pathology and disability

BACKGROUND

The role of the glymphatic system in multiple sclerosis (MS)-related disability remains underexplored. Diffusion-tensor image analysis along the perivascular space (DTI-ALPS) offers a non-invasive method to assess glymphatic function.

OBJECTIVE

To evaluate glymphatic function in MS patients with lower and higher disability.

METHODS

This study included 118 MS patients who underwent structural, diffusion-weighted imaging, and clinical assessment. The participants were divided into lower (MS-L, n = 57) and higher disability (MS-H, n = 61) subgroups. Brain parenchymal fraction (BPF), lesion load (LL), and DTI-ALPS index were measured. Subgroup differences and correlations between DTI-ALPS index and other measures were explored. Logistic regression was performed to evaluate BPF, LL, and DTI-ALPS index in classifying lower and higher disability patients.

RESULTS

Significant differences in DTI-ALPS index between MS-H and MS-L (d = -0.71, false discovery rate-corrected p-value (p-FDR) = 0.001) were found. The DTI-ALPS index correlated significantly with disease duration (rp = -0.29, p-FDR = 0.002) and EDSS (rsp = -0.35, p-FDR = 0.0002). It also showed significant correlations with BPF and LL. DTI-ALPS index and LL were significant predictors of disability subgroup (DTI-ALPS: odds ratio (OR) = 1.77, p = 0.04, LL: OR = 0.94, p = 0.02).

CONCLUSION

Our findings highlight DTI-ALPS index as an imaging biomarker in MS, suggesting the involvement of glymphatic impairment in MS pathology, although further research is needed to elucidate its role in contributing to MS-related disability.

Markers of secondary progression in multiple sclerosis

INTRODUCTION

There is no globally accepted definition of Secondary Progressive Multiple Sclerosis (SPMS) or set of unambiguous clinical, radiological, or other criteria that can accurately identify patients who transition to SPMS. Thus, the SPMS diagnosis is almost always a retrospective and frequently delayed process.

OBJECTIVE

The aim of this study was to elucidate the current understanding of phenotypic changes throughout MS course and provide insights into the detection of SPMS from the available literature on this diagnostic landscape.

METHODS

Comprehensive literature review aiming at detecting the transition from RRMS to SPMS. A search for relevant publications was conducted across different databases, scrutinizing studies that investigated tools and biomarkers for an accurate diagnosis of SPMS.

RESULTS

62 studies from the past two decades were included. The EDSS-plus was shown to be more sensitive than the EDSS alone in identifying disability progression. We found some helpful indicators for diagnosing SPMS, including cognitive impairment, particularly on working memory, information processing speed, and verbal fluency; presence of slowly expanding lesions on MRI; thinning of retinal layers on OCT. Also, glial markers as Glial Fibrillary Acidic Protein and Chitinase-3-like protein 1 might be more suitable to identify the conversion to progressive disease than Neurofilament light chain. Certain subjective symptoms seem to be more prevalent in the SPMS phase, although further studies are needed to understand whether patient reported outcomes' measures (PROMs) and which ones could be useful in detecting the transition to a progressive phenotype.

CONCLUSION

Our review highlights the emergence of useful biomarkers in early detection of progression of MS, such as cognitive impairment, MRI, and glial markers. We are getting closer to revolutionising the SPMS diagnosis and clinical management as we get a deeper understanding of these biomarkers.

Alzheimer disease-related biomarkers and cancer-related cognitive decline: the Thinking and Living with Cancer study

PURPOSE

We evaluated whether plasma Alzheimer disease (AD)-related biomarkers were associated with cancer-related cognitive decline among older breast cancer survivors.

METHODS

We included survivors aged 60-90 years with primary stage 0-III breast cancers (n = 236) and frequency-matched noncancer control paricipant (n = 154) who passed a cognitive screen and had banked plasma specimens. Participants were assessed at baseline (presystemic therapy) and annually for up to 60 months. Cognition was measured using tests of attention, processing speed, and executive function and learning and memory; perceived cognition was measured by the Functional Assessment of Cancer Therapy-Cognitive Function v3 Perceived Cognitive Impairments. Baseline plasma neurofilament light, glial fibrillary acidic protein, β-amyloid 42 and 40 and phosphorylated tau 181 were assayed using single molecule arrays. Mixed models tested associations between cognition and baseline AD biomarkers, time, group (survivor vs control participant), and their 2- and 3-way interactions, controlling for age, race, Wide Range 4 Achievement Test Word Reading score, comorbidity, and body mass index; 2-sided P values of .05 were considered statistically significant.

RESULTS

There were no group differences in baseline AD-related biomarkers except survivors had higher baseline neurofilament light levels than control participants (P = .013). Survivors had lower adjusted longitudinal attention, processing speed, and executive function than control participants starting from baseline and continuing over time (P ≤ .002). However, baseline AD-related biomarker levels were not independently associated with adjusted cognition over time, except control participants had lower attention, processing speed, and executive function scores with higher glial fibrillary acidic protein levels (P = .008).

CONCLUSION

The results do not support a relationship between baseline AD-related biomarkers and cancer-related cognitive decline. Further investigation is warranted to confirm the findings, test effects of longitudinal changes in AD-related biomarkers, and examine other mechanisms and factors affecting cognition presystemic therapy.

Prevalence of elevated sNFL in a real-world setting: Results on 908 patients with different multiple sclerosis types and treatment conditions

BACKGROUND

In the field of research for new validated surrogate biomarkers of treatment efficacy, disease activity and progression in Multiple Sclerosis (MS), serum neurofilament light-chain (sNFL) are actually the best candidate for MS patient monitoring. However, before they can be implemented in clinical practice, their usefulness as additional red flag routine measure must be demonstrated. To tackle the problem, this real-life cross-sectional study at the Regional Referring Center for Multiple Sclerosis (CRESM) aims to characterize sNFL levels and prevalence of elevated sNFL, according to our age-dependent cut-off values, in a large group of patients with different types of MS and treatment conditions.

METHODS

908 serum samples from as many MS patients being admitted at CRESM for diagnostic definition and/or during routinary treatment monitoring were consecutively collected between January 2019 and January 2020. sNFL levels were measured by single molecule array (Simoa™) technology on SR-X instrument using NF-light assays (Quanterix); results were interpreted using previously published cut-off values.

RESULTS

Primary and Secondary Progressive MS (PPMS, SPMS) forms demonstrate higher levels and prevalence of elevated sNFL (PPMS= 32 %, SPMS= 21 %) compared to the Relapse and Remitting one (RRMS = 12 %). Besides, naïve samples of RRMS and PPMS subtypes showed higher prevalence of elevated sNFL (RRMS naïve= 31 %, PPMS naïve=67 %) compared to samples from patients treated for more than 12 months (RRMS treat>12m= 9 %, PPMS treat>12m= 19 %); treated SPMS patients demonstrated higher sNFL levels and a prevalence (22 %) of elevated sNFL compared to RRMS treated patients. Focusing on RRMS, no statistical difference was found between groups of patients treated for whatever time (up to or more than 60 months) and with either DMT type (high or low-efficacy DMT). Finally, RRMS patients treated with all DMTs for more than 12 months, with the exception of teriflunomide and alemtuzumab showed a prevalence of elevated sNFL in the range of 5-10 %.

CONCLUSION

in a real-world setting comprising about 1000 MS patients, sNFL quantification was elevated in 5-to-67 % of patients, in different MS forms and treatment conditions. Elevated levels of sNFL must be considered a red-flag suggesting the need of a further clinical monitoring in any circumstance, as it can be indicative of new inflammation, ongoing degeneration or co-morbidities. This study supports the introduction of sNFL quantification in everyday patient management.

Insights into Dysregulated Neurological Biomarkers in Cancer

The link between neurodegenerative diseases (NDs) and cancer has generated greater interest in biomedical research, with decades of global studies investigating neurodegenerative biomarkers in cancer to better understand possible connections. Tau, amyloid-β, α-synuclein, SOD1, TDP-43, and other proteins associated with nervous system diseases have also been identified in various types of solid and malignant tumors, suggesting a potential overlap in pathological processes. In this review, we aim to provide an overview of current evidence on the role of these proteins in cancer, specifically examining their effects on cell proliferation, apoptosis, chemoresistance, and tumor progression. Additionally, we discuss the diagnostic and therapeutic implications of this interconnection, emphasizing the importance of further research to completely comprehend the clinical implications of these proteins in tumors. Finally, we explore the challenges and opportunities in targeting these proteins for the development of new targeted anticancer therapies, providing insight into how to integrate knowledge of NDs in oncology research.

Characteristic Profiling of Soluble Factors in the Cerebrospinal Fluid of Patients With Neurosyphilis

BACKGROUND

Soluble inflammatory factors in the cerebrospinal fluid (CSF) of patients with neurosyphilis have been investigated with low-throughput technology. This study aimed to illustrate the characteristics of soluble factor profiles in CSF of patients with neurosyphilis.

METHODS

We measured the concentrations of 45 cytokines, chemokines, and growth factors in CSF from 112 untreated syphilis cases, including latent syphilis (LS), asymptomatic neurosyphilis (ANS), meningeal neurosyphilis (MNS), meningovascular neurosyphilis (MVNS), paralytic dementia (PD), and ocular syphilis (OS).

RESULTS

Thirty-three differentially expressed soluble factors (DeSFs) were categorized into 3 clusters. DeSF scores of clusters 1 and 2 (DeSFS1 and DeSFS2) were positively correlated with elevated neopterin and neurofilament light subunit (NF-L) concentration, respectively. DeSF scores of cluster 3 were positively correlated with white blood cells, protein, NF-L, and neopterin. Patients with LS, ANS, and OS exhibited an overall lower abundance of DeSFs. Patients with PD exhibited significantly increased levels of clusters 1 and 3, and the highest total DeSF score, whereas patients with MNS and MVNS showed enhanced levels of cluster 2. Receiver operating characteristic analysis revealed that DeSFS1 effectively discriminated PD, and DeSFS2 discriminated MNS/MVNS with high accuracy.

CONCLUSIONS

Patients with neurosyphilis at different stages have distinctive patterns of soluble factors in CSF, which are correlated with immune status and neuronal damage.

Real-World Study of Serum Neurofilament Light Chain Levels in Ocrelizumab-Treated People with Relapsing Multiple Sclerosis

Serum neurofilament light chain (sNfL) levels have been proposed as a biomarker of the clinical activity, disability progression, and response to treatment of people with multiple sclerosis (PwMS); however, questions remain about its implementation in clinical practice. Ocrelizumab (OCR) has proven effective in improving clinical and radiological outcomes and reducing sNfL levels. This real-life study followed the sNfL levels of 30 PwMS treated for 12 months with OCR and evaluated the usefulness of this biomarker for their short-term prognosis, considering expanded disability status scale (EDSS), annualized relapse rate (ARR), radiological activity, and NEDA-3 values. OCR reduced ARR in 83% of PwMS and radiological activity in 80%. EDSS was maintained, while NEDA-3 was achieved in 70% at 12 months. OCR produced an early reduction in sNfL levels (at 3 months). At baseline, greater MRI-evaluated radiological activity was associated with higher sNfL levels. sNfL levels over the first 12 months of treatment did not predict a suboptimal response or sustained control of the disease. Longer-term studies are needed to explore the predictive usefulness of sNfL levels in PwMS treated with high-efficacy drugs.

Matching proposed clinical and MRI criteria of aggressive multiple sclerosis to serum and cerebrospinal fluid markers of neuroaxonal and glial injury

BACKGROUND

Definitions of aggressive MS employ clinical and MR imaging criteria to identify highly active, rapidly progressing disease courses. However, the degree of overlap between clinical and radiological parameters and biochemical markers of CNS injury is not fully understood. Aim of this cross-sectional study was to match clinical and MR imaging hallmarks of aggressive MS to serum/CSF markers of neuroaxonal and astroglial injury (neurofilament light chain (sNfL, cNfL), and glial fibrillary acidic protein (sGFAP, cGFAP)).

METHODS

We recruited 77 patients with relapsing-remitting MS (RRMS) and 22 patients with clinically isolated syndrome. NfL and GFAP levels in serum and CSF were assessed using a single-molecule-array HD-1-analyzer. A general linear model with each biomarker as a dependent variable was computed. Clinical and imaging criteria of aggressive MS, as recently proposed by the ECTRIMS Consensus Group, were modeled as independent variables. Other demographic, clinical or laboratory parameters, were modeled as covariates. Analyses were repeated in a homogenous subgroup, consisting only of newly diagnosed, treatment-naïve RRMS patients presenting with an acute relapse.

RESULTS

After adjusting for covariates and multiplicity of testing, sNfL and cNfL concentrations were strongly associated with the presence of ≥2 gadolinium-enhancing lesions (psNfL = 0.00008; pcNfL = 0.004) as well as the presence of infratentorial lesions on MRI (psNfL = 0.0003; pcNfL < 0.004). No other clinical and imaging criteria of aggressive MS correlated significantly with NfL or GFAP in serum and CSF. In the more homogeneous subgroup, sNfL still was associated with the presence of ≥2 gadolinium-enhancing lesions (psNfL = 0.001), presence of more than 20 T2-lesions (psNfL = 0.049) as well as the presence of infratentorial lesions on MRI (psNfL = 0.034), while cNfL was associated with the presence of ≥2 gadolinium-enhancing lesions (psNfL = 0.011) and presence of more than 20 T2-lesions (psNfL = 0.029).

CONCLUSIONS

Among proposed risk factors for an aggressive disease course, MRI findings but not clinical characteristics correlated with sNfL and cNfL as a marker of neuroaxonal injury and should be given appropriate weight considering MS prognosis and therapy. No significant correlation was detected for GFAP alone.

Inflammatory and neurodegenerative serum protein biomarkers increase sensitivity to detect clinical and radiographic disease activity in multiple sclerosis

The multifaceted nature of multiple sclerosis requires quantitative biomarkers that can provide insights related to diverse physiological pathways. To this end, proteomic analysis of deeply-phenotyped serum samples, biological pathway modeling, and network analysis were performed to elucidate inflammatory and neurodegenerative processes, identifying sensitive biomarkers of multiple sclerosis disease activity. Here, we evaluated the concentrations of > 1400 serum proteins in 630 samples from three multiple sclerosis cohorts for association with clinical and radiographic new disease activity. Twenty proteins were associated with increased clinical and radiographic multiple sclerosis disease activity for inclusion in a custom assay panel. Serum neurofilament light chain showed the strongest univariate correlation with gadolinium lesion activity, clinical relapse status, and annualized relapse rate. Multivariate modeling outperformed univariate for all endpoints. A comprehensive biomarker panel including the twenty proteins identified in this study could serve to characterize disease activity for a patient with multiple sclerosis.

Determination of systemic inflammatory biomarkers in multiple sclerosis

Background

Multiple sclerosis (MS) is one of the most common demyelinating diseases of the central nervous system. We aimed to investigate serum and cerebrospinal fluid levels of different laboratory inflammatory biomarkers in patients with MS.

Methods

A total of 120 subjects participated in the study, 60 of whom were diagnosed with MS, 30 with the final diagnosis of non-inflammatory diseases of the central nervous system (CNS), and 30 healthy subjects representing the control group. Regarding the progression of radiological findings after 2 years from the initial diagnosis, the MS group was divided into stationary radiological findings (n=30) and radiologically proven disease progression (n=30). In all patients, we analyzed levels of laboratory inflammatory biomarkers: C reactive protein (CRP), Neutrophil-to-lymphocyte ratio (NLR), Growth differentiation factor 15 (GDF15) in serum samples, and neurofilaments (NFs) in cerebrospinal fluid (CSF). NFs and GDF15 were analyzed initially, while CRP and NLR values were analyzed initially and after two years.

Results

We found statistically lower GDF15 values and initial CRP values in the MS group regarding the group with non-inflammatory diseases of the CNS (p<0.0001). On the other side, we determined a significant elevation of laboratory markers CRP and NLR, initially and after a two-year period, in the MS subgroup with the progression of magnetic resonance imaging (MRI) findings (p<0.0001 and p=0.050, respectively). Also, we found a positive correlation between CRP and NFs (r=0.243, p=0.04), as well as a positive correlation between CRP and GDF15 in patients with MS (r=0.769, p<0.0001).

Conclusions

We found a significant elevation of laboratory markers of systemic inflammation, CRP, and NLR in MS patients who developed disease progression based on MRI findings. There is a need for further studies to validate current parameters to be considered as useful markers of MS activity and disability.

The relationship between serum astroglial and neuronal markers and AQP4 and MOG autoantibodies

BACKGROUND

Certain demyelinating disorders, such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) exhibit serum autoantibodies against aquaporin-4 (αAQP4) and myelin oligodendrocyte glycoprotein (αMOG). The variability of the autoantibody presentation warrants further research into subtyping each case.

METHODS

To elucidate the relationship between astroglial and neuronal protein concentrations in the peripheral circulation with occurrence of these autoantibodies, 86 serum samples were analyzed using immunoassays. The protein concentration of glial fibrillary acidic protein (GFAP), neurofilament light chain (NFL) and tau protein was measured in 3 groups of subcategories of suspected NMOSD: αAQP4 positive (n = 20), αMOG positive (n = 32) and αMOG/αAQP4 seronegative (n = 34). Kruskal-Wallis analysis, univariate predictor analysis, and multivariate logistic regression with ROC curves were performed.

RESULTS

GFAP and NFL concentrations were significantly elevated in the αAQP4 positive group (p = 0.003; p = 0.042, respectively), and tau was elevated in the αMOG/αAQP4 seronegative group (p < 0.001). A logistic regression model to classify serostatus was able to separate αAQP4 seropositivity using GFAP + tau, and αMOG seropositivity using tau. The areas under the ROC curves (AUCs) were 0.77 and 0.72, respectively. Finally, a combined seropositivity versus negative status logistic regression model was generated, with AUC = 0.80.

CONCLUSION

The 3 markers can univariately and multivariately classify with moderate accuracy the samples with seropositivity and seronegativity for αAQP4 and αMOG.

Body fluid markers for multiple sclerosis and differential diagnosis from atypical demyelinating disorders

INTRODUCTION

Body fluid markers could be helpful to predict the conversion into clinically definite multiple sclerosis (MS) in people with a first demyelinating event of the central nervous system (CNS). Consequently, biomarkers such as oligoclonal bands, which are integrated in the current MS diagnostic criteria, could assist early MS diagnosis.

AREAS COVERED

This review examines existing knowledge on a broad spectrum of body fluid markers in people with a first CNS demyelinating event, explores their potential to predict conversion to MS, to assess MS disease activity, as well as their utility to differentiate MS from atypical demyelinating disorders such as neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein associated disease.

EXPERT OPINION

This field of research has shown a dramatic increase of evidence, especially in the last decade. Some biomarkers are already established in clinical routine (e.g. oligoclonal bands) while others are currently implemented (e.g. kappa free light chains) or considered as breakthroughs (e.g. neurofilament light). Determination of biomarkers poses challenges for continuous monitoring, especially if exclusively detectable in cerebrospinal fluid. A handful of biomarkers are measurable in blood which holds a significant potential.

Serum neurofilament light as a potential marker of illness duration in bipolar disorder

INTRODUCTION

Investigation on specific biomarkers for diagnostic or prognostic usage in mental diseases and especially bipolar disorder BD seems to be one outstanding field in current research. Serum neurofilament light (sNfL), a marker for neuro-axonal injury, is increased in various acute and chronic neurological disorders, but also neuro-psychiatric conditions, including affective disorders. The aim of our study was to determine a potential relation between a neuron-specific marker like sNfL and different clinical states of BD.

METHODS

In the current investigation, 51 patients with BD and 35 HC were included. Mood ratings with the Hamilton depression scale (HAMD) and the Young mania rating scale (YMRS) have been included. Illness duration was defined as the period from the time of diagnosis out of self-report and medical records. sNFL was quantified by a commercial ultrasensitive single molecule array (Simoa).

RESULTS

There was a significant positive correlation between the number of manic episodes in the past and sNfL, controlled for age and duration of illness. (R = 0.49, p = 0.03) Depressive episodes were not associated to sNfL values. (R = 0.311, p = n.s.) Patients with >3 years of illness duration showed significantly higher levels of sNfL (M18.59; SD 11.89) than patients with shorter illness duration (M = 12.38, p = 0.03) and HC (M = 11.35, p = 0.02). Patients with <3 years of illness and HC did not differ significantly in sNfL levels.

DISCUSSION

Interestingly, individuals with BD and HC did not differ in sNFL levels in general. Nevertheless, looking at the BD cohort more specifically, we found that individuals with BD with longer duration of illness (>3 years) had higher levels of sNfL than those with an illness duration below 3 years. Our results confirm previous reports on the relation of neuro-axonal injury as evidenced by sNfL and illness specific variables in bipolar disorder. Further studies are needed to clarify if sNfL may predict the disease course and/or indicated response to treatment regimes.

Studying serum neurofilament light chain levels as a potential new biomarker for small fiber neuropathy

BACKGROUND AND PURPOSE

Diagnosing small fiber neuropathies can be challenging. To address this issue, whether serum neurofilament light chain (sNfL) could serve as a potential biomarker of damage to epidermal Aδ- and C-fibers was tested.

METHODS

Serum NfL levels were assessed in 30 patients diagnosed with small fiber neuropathy and were compared to a control group of 19 healthy individuals. Electrophysiological studies, quantitative sensory testing and quantification of intraepidermal nerve fiber density after skin biopsy were performed in both the proximal and distal leg.

RESULTS

Serum NfL levels were not increased in patients with small fiber neuropathy compared to healthy controls (9.1 ± 3.9 and 9.4 ± 3.8, p = 0.83) and did not correlate with intraepidermal nerve fiber density at the lateral calf or lateral thigh or with other parameters of small fiber impairment.

CONCLUSION

Serum NfL levels cannot serve as a biomarker for small fiber damage.

Serum neurofilament light chain correlations in patients with a first clinical demyelinating event in the REFLEX study: a post hoc analysis

Background

In REFLEX, subcutaneous interferon beta-1a (sc IFN β-1a) delayed the onset of multiple sclerosis (MS) in patients with a first clinical demyelinating event (FCDE).

Objectives

This post hoc analysis aimed to determine whether baseline serum neurofilament light (sNfL) chain can predict conversion to MS and whether correlations exist between baseline sNfL and magnetic resonance imaging (MRI) metrics.

Methods

sNfL was measured for 494 patients who received sc IFN β-1a 44 μg once weekly (qw; n = 168), three times weekly (tiw; n = 161), or placebo (n = 165) over 24 months. Median baseline sNfL (26.1 pg/mL) was used to define high/low sNfL subgroups. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox's proportional hazard model to determine factors influencing the risk of conversion to MS. Kaplan-Meier estimates calculated median time-to-conversion to MS (McDonald 2005 criteria) or clinically definite MS (CDMS; Poser criteria). Correlations between sNfL and MRI findings were assessed using Spearman's rank correlation coefficient (r).

Results

Multivariable models indicated that high baseline sNfL was associated with the likelihood of converting to MS and inversely to time-to-conversion (HR = 1.3, 95% CI: 1.03-1.64; p = 0.024). Significant additional factors affecting conversion to McDonald MS were on-study treatment (sc IFN β-1a/placebo; qw: HR = 0.59, 95% CI: 0.46-0.76; tiw: HR = 0.45, 95% CI: 0.34-0.59), classification of FCDE (monofocal/multifocal; HR = 0.69, 95% CI: 0.55-0.85), and most baseline imaging findings (T2 and T1 gadolinium-enhancing [Gd+] lesions; HR = 1.02, 95% CI: 1.01-1.03 and HR = 1.07, 95% CI: 1.03-1.11); all p ⩽ 0.001. Conversion to CDMS showed similar results. At month 24, sNfL was strongly correlated with a mean number of combined unique active (r = 0.71), new T2 (r = 0.72), and new T1 Gd+ (r = 0.60) lesions; weak correlations were observed between sNfL and clinical outcomes for all treatment groups.

Conclusion

Higher baseline sNfL was associated with an increased risk of MS conversion, a risk that was mitigated by treatment with sc IFN β-1a tiw.

Trial registration

ClinicalTrials.gov identifier: NCT00404352. Date registered: 28 November 2006.

Blood metabolomic and transcriptomic signatures stratify patient subgroups in multiple sclerosis according to disease severity

There are no blood-based biomarkers distinguishing patients with relapsing-remitting (RRMS) from secondary progressive multiple sclerosis (SPMS) although evidence supports metabolomic changes according to MS disease severity. Here machine learning analysis of serum metabolomic data stratified patients with RRMS from SPMS with high accuracy and a putative score was developed that stratified MS patient subsets. The top differentially expressed metabolites between SPMS versus patients with RRMS included lipids and fatty acids, metabolites enriched in pathways related to cellular respiration, notably, elevated lactate and glutamine (gluconeogenesis-related) and acetoacetate and bOHbutyrate (ketone bodies), and reduced alanine and pyruvate (glycolysis-related). Serum metabolomic changes were recapitulated in the whole blood transcriptome, whereby differentially expressed genes were also enriched in cellular respiration pathways in patients with SPMS. The final gene-metabolite interaction network demonstrated a potential metabolic shift from glycolysis toward increased gluconeogenesis and ketogenesis in SPMS, indicating metabolic stress which may trigger stress response pathways and subsequent neurodegeneration.

Guidance for use of neurofilament light chain as a cerebrospinal fluid and blood biomarker in multiple sclerosis management

Neurofilament light chain (NfL) is a long-awaited blood biomarker that can provide clinically useful information about prognosis and therapeutic efficacy in multiple sclerosis (MS). There is now substantial evidence for this biomarker to be used alongside magnetic resonance imaging (MRI) and clinical measures of disease progression as a decision-making tool for the management of patients with MS. Serum NfL (sNfL) has certain advantages over traditional measures of MS disease progression such as MRI because it is relatively noninvasive, inexpensive, and can be repeated frequently to monitor activity and treatment efficacy. sNfL levels can be monitored regularly in patients with MS to determine change from baseline and predict subclinical disease activity, relapse risk, and the development of gadolinium-enhancing (Gd+) lesions. sNfL does not replace MRI, which provides information related to spatial localisation and lesion stage. Laboratory platforms are starting to be made available for clinical application of sNfL in several countries. Further work is needed to resolve issues around comparisons across testing platforms (absolute values) and normalisation (reference ranges) in order to guide interpretation of the results.

Visual outcome measures in clinical trials of remyelinating drugs

One of the most promising approaches to delay, prevent or reverse disability progression in multiple sclerosis (MS) is to enhance endogenous remyelination and limit axonal degeneration. In clinical trials of remyelinating drugs, there is a need for reliable, sensitive and clinically relevant outcome measures. The visual pathway, which is frequently affected by MS, provides a unique model system to evaluate remyelination of acute and chronic MS lesions in vivo and non-invasively. In this review, we discuss the different measures that have been used and scrutinise visual outcome measure selection in current and future remyelination trials.

The use of synaptic biomarkers in cerebrospinal fluid to differentiate behavioral variant of frontotemporal dementia from primary psychiatric disorders and Alzheimer's disease

BACKGROUND

Lack of early molecular biomarkers in sporadic behavioral variants of frontotemporal dementia (bvFTD) and its clinical overlap with primary psychiatric disorders (PPD) hampers its diagnostic distinction. Synaptic dysfunction is an early feature in bvFTD and identification of specific biomarkers might improve its diagnostic accuracy. Our goal was to understand the differential diagnostic potential of cerebrospinal fluid (CSF) synaptic biomarkers in bvFTD versus PPD and their specificity towards bvFTD compared with Alzheimer's disease (AD) and controls. Additionally, we explored the association of CSF synaptic biomarkers with social cognition, cognitive performance, and disease severity in these clinical groups.

METHODS

Participants with probable bvFTD (n = 57), PPD (n = 71), AD (n = 60), and cognitively normal controls (n = 39) with available CSF, cognitive tests, and disease severity as frontotemporal lobar degeneration-modified clinical dementia rating scale (FTLD-CDR) were included. In a subset of bvFTD and PPD cases, Ekman 60 faces test scores for social cognition were available. CSF synaptosomal-associated protein 25 (SNAP25), neurogranin (Ng), neuronal pentraxin 2 (NPTX2), and glutamate receptor 4 (GluR4) were measured, along with neurofilament light (NfL), and compared between groups using analysis of covariance (ANCOVA) and logistic regression. Diagnostic accuracy was assessed using ROC analyses, and biomarker panels were selected using Wald's backward selection. Correlations with cognitive measures were performed using Pearson's partial correlation analysis.

RESULTS

NPTX2 concentrations were lower in the bvFTD group compared with PPD (p < 0.001) and controls (p = 0.003) but not compared with AD. Concentrations of SNAP25 (p < 0.001) and Ng (p < 0.001) were elevated in patients with AD versus those with bvFTD and controls. The modeled panel for differential diagnosis of bvFTD versus PPD consisted of NfL and NPTX2 (AUC = 0.96, CI: 0.93-0.99, p < 0.001). In bvFTD versus AD, the modeled panel consisted of NfL, SNAP25, Ng, and GluR4 (AUC = 0.86, CI: 0.79-0.92, p < 0.001). In bvFTD, lower NPTX2 (Pearson's r = 0.29, p = 0.036) and GluR4 (Pearson's r = 0.34, p = 0.014) concentrations were weakly associated with worse performance of total cognitive score. Lower GluR4 concentrations were also associated with worse MMSE scores (Pearson's r = 0.41, p = 0.002) as well as with worse executive functioning (Pearson's r = 0.36, p = 0.011) in bvFTD. There were no associations between synaptic markers and social cognition or disease severity in bvFTD.

CONCLUSION

Our findings of involvement of NTPX2 in bvFTD but not PPD contribute towards better understanding of bvFTD disease pathology.

Hallmarks of spinal cord pathology in multiple sclerosis

A disparity exists between spinal cord and brain involvement in multiple sclerosis (MS), each independently contributing to disability. Underlying differences between brain and cord are not just anatomical in nature (volume, white/grey matter organization, vascularization), but also in barrier functions (differences in function and composition of the blood-spinal cord barrier compared to blood-brain barrier) and possibly in repair mechanisms. Also, immunological phenotypes seem to influence localization of inflammatory activity. Whereas the brain has gained a lot of attention in MS research, the spinal cord lags behind. Advanced imaging techniques and biomarkers are improving and providing us with tools to uncover the mechanisms of spinal cord pathology in MS. In the present review, we elaborate on the underlying anatomical and physiological factors driving differences between brain and cord involvement in MS and review current literature on pathophysiology of spinal cord involvement in MS and the observed differences to brain involvement.

[Neurofilament light chain: a diagnostic potential for multiple sclerosis]

OBJECTIVE

To evaluate the influence of disease activity, the degree of patient disability and pathogenetic therapy on the concentration of neurofilament light chain (NFL) in the blood serum of patients with multiple sclerosis (MS).

MATERIAL AND METHODS

One hundred and fourteen patients (84 women and 30 men) with definite MS were examined. The concentration of NFL in the blood serum of patients with MS was determined by enzyme immunoassay. The level of NFL was analyzed depending on the characteristics of the course and activity of the demyelinating process, the severity of neurological disorders as well as disease modifying drugs (DMDs).

RESULTS

An NFL level equal to or greater than 4201 pg/ml was found to be associated with a higher risk of developing a clinical exacerbation in the next 4 months. In patients with progression of disability over the next 2 years, the initial concentration of NFL was significantly higher than in the group with a stable EDSS score. The NFL level (4943 pg/ml and higher), which may be a predictor of increased disability in the next two years, was established.

CONCLUSION

The study demonstrates the possibility of using serum NFL levels as a diagnostic marker of possible exacerbation, as well as predicting disability in patients with MS.

Multi-modal neuroimaging signatures predict cognitive decline in multiple sclerosis: A 5-year longitudinal study

BACKGROUND

Cognitive impairment is a hallmark of multiple sclerosis (MS) but is usually an under-recorded symptom of disease progression. Identifying the predictive signatures of cognitive decline in people with MS (pwMS) over time is important to ensure effective preventative treatment strategies. Structural and functional brain characteristics as measured by various magnetic resonance (MR) methods have been correlated with variation in cognitive function in MS, but typically these studies are limited to a single MR modality and/or are cross-sectional designs. Here we assess the predictive value of multiple different MR modalities in relation to cognitive decline in pwMS over 5 years.

METHODS

A cohort of 43 pwMS was assessed at baseline and 5 years follow-up. Baseline (input) data consisted of 70 multi-modal MRI measures for different brain regions including magnetic resonance spectroscopy (MRS), diffusion tensor imaging (DTI) and standard volumetrics. Age, sex, disease duration and treatment were included as clinical inputs. Cognitive function was assessed using the Audio Recorded Cognitive Screen (ARCS) and the Symbol Digit Modalities Test (SDMT). Prediction modelling was performed using the machine learning package - GLMnet, where a penalised regression was applied to identify multi-modal signatures with the most predictive value (and the least error) for each outcome.

RESULTS

The multi-modal approach to neuroimaging was able to accurately predict cognitive decline in pwMS. The best performing model for change in total ARCS (tARCS) included 16 features from across the various MR modalities and explained 54 % of the variation in change over time (R2=0.54, 95 % CI=0.48-0.51). The features included nine MRS, four volumetric and two DTI parameters. The model also selected disease duration, but not treatment, as a predictive feature. By comparison, the best model for SDMT included several of the same above features and explained 39 % of the change over time (R2=0.39, 95 % CI=0.48-0.51). Conventional volumetric measures were about half as good at predicting change in tARCS score compared to the best multi-modal model (R2=0.26 95 % CI:0.22-0.29). The clinical interpretation of the best predictive model for change in tARCS showed that cognitive decline could be predicted with >90 % accuracy in this cohort (AUC=0.92, SE=0.86 - 0.94).

CONCLUSION

Multi-modal MRI signatures can predict cognitive decline in a cohort of pwMS over 5 years with high accuracy. Future studies will benefit from the inclusion of even more MR modalities e.g., functional MRI, quantitative susceptibility mapping, magnetisation transfer imaging, as well as other potential predictors e.g., genetic and environmental factors. With further validation, this signature could be used in future trials with high-risk patients to personalise the management of cognitive decline in pwMS, even in the absence of relapses.

Serum neurofilament light chain as an early diagnostic biomarker for critical illness polyneuropathy

BACKGROUND

Critical illness polyneuropathy (CIP) commonly occurs in critical care unit (CCU) patients, but timely diagnosis can be challenging. Therefore, new biomarkers, such as serum neurofilament light chain (sNfL), could help to improve early identification of patients with this condition.

METHODS

CIP was diagnosed or excluded with neurological assessment and nerve conduction measurement in a prospective study of CCU patients. sNfL and secondary predictors for neuropathy (neuron-specific enolase (NSE), S100, folic acid, and vitamin B12) were measured at admission. Cases and controls were compared regarding the predictors.

RESULTS

Nineteen patients met the inclusion criteria. CIP was considered definitely or most likely present in seven (37%, cases) and definitely or most likely absent in 12 individuals (63%, controls). At admission, sNfL levels were significantly higher in the cases than in the controls: 405 (IQR 77 to 835) vs. 27 (IQR 12 to 90) pg/mL; difference of medians 375, 95% confidence interval [14, 736], pg/mL; P=0.04. We found no significant differences regarding the secondary predictors at baseline. Cases had longer durations of CCU stay (median 19 (IQR 11 to 44) vs. 8 (IQR five to ten) and increased mortality (57% vs. 33% deceased) compared to controls.

CONCLUSIONS

Levels of serum neurofilament light chain are higher in patients who develop CIP soon after CCU admission and might be helpful in identifying those individuals early.

Cerebrospinal fluid neurofilament light chains predicts early disease-activity in Multiple Sclerosis

BACKGROUND

Among biomarkers of axonal damage, neurofilament light chains (NFL) seem to play a major role, representing a promising and interesting tool in Multiple Sclerosis (MS). Our aim was to explore the predictive role of cerebrospinal fluid (CSF) NFL in patients with a recent diagnosis of MS, naïve to any MS therapy.

METHODS

We retrospectively collected data of patients diagnosed with MS, referred to the Neurology Clinic of the University-Hospital G. Rodolico of Catania between January 1st 2005 and December 31st 2015. All patients underwent CSF collection at the time of MS diagnosis and were followed-up for at least three years afterwards. NFL levels were measured in CSF samples with Simoa NFLight advantage kit at the CRESM (University Hospital San Luigi Gonzaga, Orbassano, Torino). NFL levels were expressed as LogNFL. Symbol Digit Modalities test (SDMT) was performed at baseline, at 1-year and at 3-year follow-up. Multivariate logistic regression analysis was performed to investigate LogNFL as a potential risk factor of different clinical outcomes.

RESULTS

244 MS patients (230 relapsing-remitting, RRMS; 94.3 %), with a mean age at diagnosis of 37.0 ± 11.1 years, were recruited. LogNFL did not correlate neither with EDSS score at diagnosis and at subsequent follow-up up to 12 years, nor with SDMT performed at diagnosis, at 1 year and at 3 years. LogNFL were an independent factor for the occurrence of at least one relapse during the first two years after MS diagnosis (OR = 2.75; 95 % CI 1.19-6.31; p = 0.02) and for the occurrence of gadolinium-enhanced (Gd+) lesions during the first 2 years from diagnosis at brain and spine MRI scans (OR = 3.45, 95 % CI 1.81-6.57; p < 0.001).

CONCLUSION

The detection of CSF NFL at the time of MS diagnosis can be a useful support to predict the two-year risk of clinical and radiological relapses, thus affecting therapeutic choices in the very early phases of the disease.

Neurofilament light chain in spinal fluid and plasma in multiple system atrophy: a prospective, longitudinal biomarker study

PURPOSE

There is a critical need for reliable diagnostic biomarkers as well as surrogate markers of disease progression in multiple system atrophy (MSA). Neurofilament light chain (NfL) has been reported to potentially meet those needs. We therefore sought to explore the value of NfL in plasma (NfL-p) in contrast to cerebrospinal fluid (NfL-c) as a diagnostic marker of MSA, and to assess NfL-p and NfL-c as markers of clinical disease progression.

METHODS

Well-characterized patients with early MSA (n = 32), Parkinson's disease (PD; n = 21), and matched controls (CON; n = 15) were enrolled in a prospective, longitudinal study of synucleinopathies with serial annual evaluations. NfL was measured using a high-sensitivity immunoassay, and findings were assessed by disease category and relationship with clinical measures of disease progression.

RESULTS

Measurements of NfL-c were highly reproducible across immunoassay platforms (Pearson, r = 0.99), while correlation between NfL-c and -p was only moderate (r = 0.66). NfL was significantly higher in MSA compared with CON and PD; the separation was essentially perfect for NfL-c, but there was overlap, particularly with PD, for NfL-p. While clinical measures of disease severity progressively increased over time, NfL-c and -p remained at stable elevated levels within subjects across serial measurements. Neither change in NfL nor baseline NfL were significantly associated with changes in clinical markers of disease severity.

CONCLUSIONS

These findings confirm NfL-c as a faithful diagnostic marker of MSA, while NfL-p showed less robust diagnostic value. The significant NfL elevation in MSA was found to be remarkably stable over time and was not predictive of clinical disease progression.

Neurofilament Light Chain in Adult and Pediatric Multiple Sclerosis: A Promising Biomarker to Better Characterize Disease Activity and Personalize MS Treatment

Many biological markers have been explored in multiple sclerosis (MS) to better quantify disease burden and better evaluate response to treatments, beyond clinical and MRI data. Among these, neurofilament light chain (Nf-L), although non-specific for this disease and found to be increased in other neurological conditions, has been shown to be the most promising biomarker for assessing axonal damage in MS, with a definite role in predicting the development of MS in patients at the first neurological episode suggestive of MS, and also in a preclinical phase. There is strong evidence that Nf-L levels are increased more in relapsing versus stable MS patients, and that they predict future disease evolution (relapses, progression, MRI measures of activity/progression) in MS patients, providing information on response to therapy, helping to anticipate clinical decisions in patients with an apparently stable evolution, and identifying patient non-responders to disease-modifying treatments. Moreover, Nf-L can contribute to the better understanding of the mechanisms of demyelination and axonal damage in adult and pediatric MS. A fundamental requirement for its clinical use is the accurate standardization of normal values, corrected for confounding factors, in particular age, sex, body mass index, and presence of comorbidities. In this review, a guide is provided to update clinicians on the use of Nf-L in clinical activity.

The relationship between serum astroglial and neuronal markers and AQP4 and MOG autoantibodies

Background

Certain demyelinating disorders, such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) exhibit serum autoantibodies against aquaporin-4 (αAQP4) and myelin oligodendrocyte glycoprotein (αMOG). The variability of the autoantibody presentation warrants further research into subtyping each case.

Methods

To elucidate the relationship between astroglial and neuronal protein concentrations in the peripheral circulation with occurrence of these autoantibodies, 86 serum samples were analyzed using immunoassays. The protein concentration of glial fibrillary acidic protein (GFAP), neurofilament light chain (NFL) and tau protein was measured in 3 groups of subcategories of suspected NMOSD: αAQP4 positive (n = 20), αMOG positive (n = 32) and αMOG/αAQP4 seronegative (n = 34). Kruskal-Wallis analysis, univariate predictor analysis, and multivariate logistic regression with ROC curves were performed.

Results

GFAP and NFL concentrations were significantly elevated in the αAQP4 positive group (p = 0.003; p = 0.042, respectively), and tau was elevated in the αMOG/αAQP4 seronegative group (p < 0.001). A logistic regression model to classify serostatus was able to separate αAQP4 seropositivity using GFAP + tau, and αMOG seropositivity using tau. The areas under the ROC curves (AUCs) were 0.77 and 0.72, respectively. Finally, a combined seropositivity versus negative status logistic regression model was generated, with AUC = 0.80.

Conclusion

The 3 markers can univariately and multivariately classify with moderate accuracy the samples with seropositivity and seronegativity for αAQP4 and αMOG.

Matrine mediated neuroprotective potential in experimental multiple sclerosis: Evidence from CSF, blood markers, brain samples and in-silico investigations

Multiple sclerosis (MS) is a debilitating, inflammatory, and demyelinating disease of the central nervous system influenced by environmental and genetic factors. Around 2.8 million people worldwide are affected by MS due to its challenging diagnosis and treatment. Our study investigates the role of the JAK/STAT and PPAR-gamma signaling pathways in the progression of multiple sclerosis. Inflammation and demyelination can be caused by dysregulation of these pathways. Modulating the STAT-3, mTOR, and PPAR-gamma signaling pathways may offer therapeutic potential for multiple sclerosis. Matrine (40 and 80 mg/kg, i.p.), a quinolizidine alkaloid derived from Sophora flavescens, has been investigated for its therapeutic potential in our laboratory. Matrine has been studied for its neuroprotective effect in neurodegenerative diseases. It inhibits inflammatory responses and promotes regeneration of damaged myelin sheaths, indicating its potential efficacy in treating multiple sclerosis. Matrine exerts its neuroprotective effect by inhibiting STAT-3 and mTOR and promoting PPAR-gamma expression.GW9662, a PPAR-gamma antagonist (2 mg/kg, i.p.), was administered to evaluate the involvement of PPAR-gamma and to compare the efficacy of matrine's potential neuroprotective effect. Matrine's interaction with the STAT-3, mTOR, and PPAR-gamma pathways in multiple Sclerosis was also validated and confirmed through insilico investigation. In addition, matrine altered the CBC profile, intensifying the clinical presentation of multiple sclerosis. In addition, we evaluated the diagnostic potential of various biological samples, including CSF, blood plasma, and brain homogenates (striatum, cortex, hippocampus, and midbrain). These samples were used to evaluate the neurochemical changes caused by neurobehavioral alterations during the progression of multiple sclerosis. These results indicate that matrine treatment ameliorated multiple sclerosis and that the mechanism underlying these effects may be closely related to the modulation of the STAT-3/mTOR/PPAR-gamma signaling pathway.

The Comparison of the Selected Parameters of Brain Injury and Interleukins in the CSF in Patients Diagnosed De Novo with RRMS Compared to the Control Group

BACKGROUND

Multiple sclerosis (MS) is a chronic autoimmune disorder affecting the central nervous system (CNS). Due to the different phenotypes of the disease and non-specific symptoms of MS, there is a great need for a validated panel of biomarkers to facilitate the diagnosis, predict disease progression, and evaluate treatment outcomes.

METHODS

We determined the levels of the parameters of brain injury (NF-H, GPAF, S100B, and UCHL1) and the selected cytokines in the cerebrospinal fluid (CSF) in 101 patients diagnosed de novo with RRMS and 75 healthy controls. All determinations were made using the Bio-Plex method.

RESULTS

We found higher levels of NF-H and GFAP in the relapsing-remitting multiple sclerosis (RRMS) group compared to the controls. The concentrations of both molecules were significantly increased in patients with Gd+ lesions on brain MRI. The level of S100B did not differ significantly between the groups. UCHL1 concentrations were higher in the control group. We found some correlations between the selected cytokines, the levels of the parameters of brain injury, and the time from the first symptoms to the diagnosis of MS.

CONCLUSIONS

The role of the above molecules in MS is promising. However, further research is warranted to define their precise functions.

Biosensors, Recent Advances in Determination of BDNF and NfL

Key biomarkers such as Brain Derived Neurotrophic Factor (BDNF) and Neurofilament light chain (NfL) play important roles in the development and progression of many neurological diseases, including multiple sclerosis, Alzheimer's disease, and Parkinson's disease. In these clinical conditions, the underlying biomarker processes are markedly heterogeneous. In this context, robust biomarker discovery is of critical importance for screening, early detection, and monitoring of neurological diseases. The difficulty of directly identifying biochemical processes in the central nervous system (CNS) is challenging. In recent years, biomarkers of CNS inflammatory response have been identified in various body fluids such as blood, cerebrospinal fluid, and tears. Furthermore, biotechnology and nanotechnology have facilitated the development of biosensor platforms capable of real-time detection of multiple biomarkers in clinically relevant samples. Biosensing technology is approaching maturity and will be deployed in communities, at which point screening programs and personalized medicine will become a reality. In this multidisciplinary review, our goal is to highlight clinical and current technological advances in the development of multiplex-based solutions for effective diagnosis and monitoring of neuroinflammatory and neurodegenerative diseases. The trend in the detection if BDNF and NfL.

Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis

Sensitive and reliable protein biomarkers are needed to predict disease trajectory and personalize treatment strategies for multiple sclerosis (MS). Here, we use the highly sensitive proximity-extension assay combined with next-generation sequencing (Olink Explore) to quantify 1463 proteins in cerebrospinal fluid (CSF) and plasma from 143 people with early-stage MS and 43 healthy controls. With longitudinally followed discovery and replication cohorts, we identify CSF proteins that consistently predicted both short- and long-term disease progression. Lower levels of neurofilament light chain (NfL) in CSF is superior in predicting the absence of disease activity two years after sampling (replication AUC = 0.77) compared to all other tested proteins. Importantly, we also identify a combination of 11 CSF proteins (CXCL13, LTA, FCN2, ICAM3, LY9, SLAMF7, TYMP, CHI3L1, FYB1, TNFRSF1B and NfL) that predict the severity of disability worsening according to the normalized age-related MS severity score (replication AUC = 0.90). The identification of these proteins may help elucidate pathogenetic processes and might aid decisions on treatment strategies for persons with MS.

Serum Neurofilaments are a reliable biomarker to early detect PML in Multiple Sclerosis patients

BACKGROUND

The earliest detection of progressive multifocal leukoencephalopathy (PML) is crucial in Natalizumab (NTZ)-treated Multiple Sclerosis (MS) patients. This study aims to assess serum Neurofilaments (sNFL) ability to early detect PML in longitudinal patients' follow-up.

METHODS

NFL were retrospectively measured in four PML cases occurred at the Regional Referring Center for MS (CRESM, Italy), in samples collected since one year before PML diagnosis, at PML diagnosis, during PML and in post-PML follow-up. sNFL levels were interpreted according to previously defined reference values. Clinical examination and EDSS were performed at each NTZ infusion. Routinary MRI was undertaken every six months; after PML diagnosis, MRI was performed according to clinical evaluation. sNFL were also measured in 45 NTZ-treated patients experiencing NEDA-3 status for at least 12 months.

RESULTS

Patients showed different PML onsets and manifestations: in 3 patients routinary brain MRI revealed radiological signs of PML preceding different clinical manifestations, while in one patient brain MRI was performed after the clinical onset. PML diagnosis was defined at the time of the first detection of JCV DNA in cerebrospinal fluid. The following different PML phases were considered: 1. Basal (up to 4 months before PML diagnosis): sNFL values were in the normal range in all patients' samples, except for one (median 9.1 pg/ml, range 6.2-15.1 pg/ml) 2. Pre-PML (within 3 months before PML diagnosis): sNFL were elevated in all available samples (median 19.50 pg/ml, range 15.50-33.80 pg/ml). 3. PML diagnosis: sNFL were elevated in all patients (median 59.20 pg/ml, range 11.1-101.50 pg/ml). 4. PML/IRIS: during this phase, sNFL levels reached their peak (median 96.35 pg/ml, range 20.5-272.9) in all patients. 5. Post-PML (recovery phase, starting from the first MRI without enhancement, up to the end of follow-up): sNFL levels showed a decrease (median 12.80 pg/ml, range 9.30-30.60); however, based on reference values, sNFL were still elevated in 2 out of 4 patients at the end of their follow-up (622 and 887 days after PML diagnosis). sNFL were always elevated when MRI scan suggested a suspicious of PML. In NEDA-3 patients, sNFL levels were in the normal range in all patients' samples (median 4.7 pg/ml, range 1.4-8.6 pg/ml).

CONCLUSION

Elevated sNFL were observed not only at PML diagnosis, but also in pre-PML phase. At PML recovery, sNFL weren't normalized in all patients' samples, suggesting ongoing neuronal degeneration. sNFL represent a reliable biomarker and should be introduced in clinical practice as an additional/alternative parameter to MRI to early detect and monitor PML.

Blood-based biomarkers for Alzheimer's disease: a multicenter-based cross-sectional and longitudinal study in China

Discrepancies in diagnostic biomarkers for Alzheimer's Disease (AD) may arise from racial disparities, risk factors, or lifestyle differences. Moreover, there has been a lack of systematic and multicenter studies to evaluate baselines of the AD biomarkers in Chinese populations. Thus, there is an urgent need for research to investigate the effectiveness of blood biomarkers for AD, specifically in the Chinese Han population, using a multicenter approach. In the present multicenter-based cross-sectional and longitudinal study, we evaluated 817 blood samples from 6 different clinical centers. We measured plasma amyloid beta (Aβ)-40, Aβ42, phosphorylated tau 181 (pTau), total tau (tTau), serum neurofilament light (NFL), and glial fibrillary acidic protein (GFAP). Additionally, 18F-florbetapir positron electron tomography and magnetic resonance imaging were also performed. A combination of the APOE genotype with plasma pTau and serum GFAP demonstrated exceptional performance in distinguishing Aβ status. Furthermore, baseline GFAP levels exhibited a strong association with cognitive decline over time and brain atrophy, with higher GFAP levels predicting a faster rate of neurodegeneration. In summary, these results validate the practicality of blood biomarkers in the Chinese Han population, encompassing various regions within China. Additionally, they emphasize the potential of pTau and GFAP as non-invasive methods for detecting and screening AD at an early stage.

Neurofilament Light Chain in Spinal Fluid and Plasma in Multiple System Atrophy - A Prospective, Longitudinal Biomarker Study

Purpose There is a critical need for reliable diagnostic biomarkers as well as surrogate markers of disease progression in multiple system atrophy (MSA). Neurofilament light chain (NfL) has been reported to potentially meet those needs. We therefore sought to explore the value of NfL in plasma (NfL-p) in contrast to CSF (NfL-c) as diagnostic marker of MSA, and to assess NfL-p and NfL-c as markers of clinical disease progression. Methods Well-characterized patients with early MSA (n=32), Parkinson's disease (PD, n=21), and matched controls (CON, n=15) were enrolled in a prospective, longitudinal study of synucleinopathies with serial annual evaluations. NfL was measured using a high sensitivity immunoassay, and findings were assessed by disease category and relationship with clinical measures of disease progression. Results Measurements of NfL-c were highly reproducible across immunoassay platforms (Pearson,r=0.99), while correlation between NfL-c and -p was only moderate (r=0.66). NfL was significantly higher in MSA compared to CON and PD; the separation was essentially perfect for NfL-c, but there was overlap, particularly with PD, for NfL-p. While clinical measures of disease severity progressively increased over time, NfL-c and -p remained at stable elevated levels within subjects across serial measurements. Neither change in NfL nor baseline NfL were significantly associated with changes in clinical markers of disease severity. Conclusions These findings confirm NfL-c as faithful diagnostic marker of MSA, while NfL-p showed less robust diagnostic value. The significant NfL elevation in MSA was found to be remarkably stable over time and was not predictive of clinical disease progression.

Inflammatory and neurodegenerative serum protein biomarkers increase sensitivity to detect disease activity in multiple sclerosis

Background/Objectives

Serum proteomic analysis of deeply-phenotyped samples, biological pathway modeling and network analysis were performed to elucidate the inflammatory and neurodegenerative processes of multiple sclerosis (MS) and identify sensitive biomarkers of MS disease activity (DA).

Methods

Over 1100 serum proteins were evaluated in >600 samples from three MS cohorts to identify biomarkers of clinical and radiographic (gadolinium-enhancing lesions) new MS DA. Protein levels were analyzed and associated with presence of gadolinium-enhancing lesions, clinical relapse status (CRS), and annualized relapse rate (ARR) to create a custom assay panel.

Results

Twenty proteins were associated with increased clinical and radiographic MS DA. Serum neurofilament light chain (NfL) showed the strongest univariate correlation with radiographic and clinical DA measures. Multivariate modeling significantly outperformed univariate NfL to predict gadolinium lesion activity, CRS and ARR.

Discussion

These findings provide insight regarding correlations between inflammatory and neurodegenerative biomarkers and clinical and radiographic MS DA.

Funding

Octave Bioscience, Inc (Menlo Park, CA).

Validating blood tests as a possible routine diagnostic assay of Alzheimer's disease

INTRODUCTION

In recent years, exciting developments in disease modifying treatments for Alzheimer's disease (AD) have made accurate and timely diagnosis of this disease a priority. Blood biomarkers (BBMs) for amyloid pathology using improved immunoassay and mass spectrometry techniques have been an area of intense research for the last 10 years and are coming to the fore, as a real prospect to be used in the clinical diagnostics of the disease.

AREAS COVERED

The following review will update and discuss blood biomarkers that will be most useful in diagnosing AD and the context necessary for their implementation.

EXPERT OPINION

It is clear we now have BBMs, and technology to measure them, that are capable of detecting amyloid pathology in AD. The challenge is to validate them across platforms and populations to incorporate them into clinical practice. It is important that implementation comes with education, we need to give clinicians the tools for appropriate use and interpretation. It is feasible that BBMs will be used to screen populations, initially for clinical trial entry but also therapeutic intervention in the foreseeable future. We now need to focus BBM research on other pathologies to ensure we accelerate the development of therapeutics for all neurodegenerative diseases.

Changes in stiffness of the optic nerve and involvement of neurofilament light chains in the course of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis

Multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), are often accompanied by optic neuritis associated with neurofilament disruption. In this study, the stiffness of the optic nerve was investigated by atomic force microscopy (AFM) in mice with induced EAE in the successive phases of the disease: onset, peak, and chronic. AFM results were compared with the intensity of the main pathological processes in the optic nerve: inflammation, demyelination, and axonal loss, as well as with the density of astrocytes, assessed by quantitative histology and immunohistochemistry. Optic nerve tissue and serum levels of neurofilament light chain protein (NEFL) were also examined by immunostaining and ELISA, respectively. The stiffness of the optic nerve in EAE mice was lower than that in control and naïve animals. It increased in the onset and peak phases and sharply decreased in the chronic phase. Serum NEFL level showed similar dynamics, while tissue NEFL level decreased in the onset and peak phases, indicating a leak of NEFL from the optic nerve to body fluids. Inflammation and demyelination gradually increased to reach the maximum in the peak phase of EAE, and inflammation slightly declined in the chronic phase, while demyelination did not. The axonal loss also gradually increased and had the highest level in the chronic phase. Among these processes, demyelination and especially axonal loss most effectively decrease the stiffness of the optic nerve. NEFL level in serum can be regarded as an early indicator of EAE, as it rapidly grows in the onset phase of the disease.

The State of the Art of Pediatric Multiple Sclerosis

Multiple sclerosis (MS) represents a chronic immune-mediated neurodegenerative disease of the central nervous system that generally debuts around the age of 20-30 years. Still, in recent years, MS has been increasingly recognized among the pediatric population, being characterized by several peculiar features compared to adult-onset disease. Unfortunately, the etiology and disease mechanisms are poorly understood, rendering the already limited MS treatment options with uncertain efficacy and safety in pediatric patients. Thus, this review aims to shed some light on the progress in MS therapeutic strategies specifically addressed to children and adolescents. In this regard, the present paper briefly discusses the etiology, risk factors, comorbidities, and diagnosis possibilities for pediatric-onset MS (POMS), further moving to a detailed presentation of current treatment strategies, recent clinical trials, and emerging alternatives. Particularly, promising care solutions are indicated, including new treatment formulations, stem cell therapies, and cognitive training methods.

Altered amide proton transfer weighted and diffusion signals in patients with multiple sclerosis: correlation with neurofilament light chain and disease duration

Objectives

To compare the signal alterations of amide proton transfer (APT), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) in white matter (WM) lesions in multiple sclerosis (MS), compared with healthy controls (HCs), and to investigate the relationships between these changes and clinical measurements such as serum neurofilament light chain (sNfL).

Materials and methods

Twenty-nine patients with relapsing-remitting MS (21 females and 8 males) and 30 HCs (23 females and 7 males) were recruited. APT-weighted (APTw) and diffusion tensor imaging (DTI) data were acquired using a 3.0-T magnetic resonance system. APTw and DTI images were registered to FLAIR-SPIR images and assessed by two neuroradiologists. MTRasym (3.5 ppm), ADC, FA values for MS and HC are calculated using mean values from all regions of interest (ROI). The ROI criteria were: (1) for MS patients, ROI were defined as MS lesions, and each lesion was identified. (2) The WM around each HC's lateral ventricle (frontal lobe, parietal lobe, and centrum semiovale) was assessed bilaterally. The diagnostic efficacy of MTRasym (3.5 ppm), ADC, and FA in the lesions of MS patients was compared using receiver operating characteristic (ROC) curve analysis. The associations between MTRasym (3.5 ppm), ADC, and FA values and the clinical measurements were investigated further.

Results

The MTRasym (3.5 ppm) and ADC values of brain lesions were increased, while FA values were decreased in patients with MS. The diagnostic area under curve (AUC) of MTRasym (3.5 ppm), ADC, and FA value was 0.891 (95% CI: 0.813, 0.970), 0.761 (95% CI: 0.647, 0.875) and 0.970 (95% CI: 0.924, 1.0), respectively. sNfL was considerably positively correlated with MTRasym (3.5 ppm) (P = 0.043, R = 0.38) and disease durations were significantly negatively correlated with FA (P = 0.046, R = -0.37).

Conclusion

Amide proton transfer-weighted (APTw) and DTI are potential imaging methods for assessing brain lesions in patients with MS at the molecular and microscopic levels, respectively. The association between APTw, DTI parameters and clinical factors implies that they may play a role in disease damage monitoring.

Neurofilament light (NfL) as biomarker in serum and CSF in status epilepticus

OBJECTIVE

We explored the potential of neurofilament light chain (NfL) in serum and cerebrospinal fluid as a biomarker for neurodestruction in status epilepticus.

METHODS

In a retrospective analysis, we measured NfL in serum and cerebrospinal fluid samples of patients with status epilepticus using a highly sensitive single-molecule array technique (Simoa). Status epilepticus was diagnosed according to ILAE criteria. Additionally, we employed an alternative classification with more emphasis on the course of status epilepticus. We used data from three large control groups to compare NfL in status epilepticus versus neurologically healthy controls.

RESULTS

We included 28 patients (mean age: 69.4 years, SD: 15 years) with a median status duration of 44 h (IQR: 80 h). Twenty-one patients (75%) suffered from convulsive status epilepticus and seven (25%) from non-convulsive status epilepticus. Six patients died (21%). Cerebrospinal fluid and serum NfL concentrations showed a high correlation (r = 0.73, p < 0.001, Pearson). The main determinant of NfL concentration was the status duration. NfL concentrations did not differ between convulsive status epilepticus and convulsive status epilepticus classified according to the ILAE or to the alternative classification without and with adjusting for status duration and time between status onset and sampling. We found no association of NfL concentration with death, treatment refractoriness, or prognostic scores.

CONCLUSION

The results suggest that neurodestruction in status epilepticus measured by NfL is mainly determined by status duration, not status type nor therapy refractoriness. Therefore, our results suggest that regarding neurodestruction convulsive and non-convulsive status epilepticus are both neurological emergencies of comparable urgency.

Validity of serum neurofilament light chain as a prognostic biomarker of disease activity in multiple sclerosis

Multiple sclerosis (MS) is a chronic demyelinating and neuroinflammatory disease of the human central nervous system with complex pathoetiology, heterogeneous presentations and an unpredictable course of disease progression. There remains an urgent need to identify and validate a biomarker that can reliably predict the initiation and progression of MS as well as identify patient responses to disease-modifying treatments/therapies (DMTs). Studies exploring biomarkers in MS and other neurodegenerative diseases currently focus mainly on cerebrospinal fluid (CSF) analyses, which are invasive and impractical to perform on a repeated basis. Recent studies, replacing CSF with peripheral blood samples, have revealed that the elevation of serum neurofilament light chain (sNfL) in the clinical stages of MS is, potentially, an ideal prognostic biomarker for predicting disease progression and for possibly guiding treatment decisions. However, there are unresolved factors (the definition of abnormal values of sNfL concentration, the standardisation of measurement and the amount of change in sNfL concentration that is significant) that are preventing its use as a biomarker in routine clinical practice for MS. This updated review critiques these recent findings and highlights areas for focussed work to facilitate the use of sNfL as a prognostic biomarker in MS management.

The role of systemic ımmune ınflammatory ındex in showing active lesion ın patients with multiple sclerosis : SII and other inflamatuar biomarker in radiological active multiple sclerosis patients

BACKGROUND

Multiple sclerosis (MS) has two pathophysiological processes, one inflammatory and the other degenerative. We investigated the relationship between active lesions on magnetic resonance imaging showing the inflammatory phase in MS patients and serum parameters that can be used as inflammatory biomarkers. Thus, we aim to detect the inflammatory period in clinical and radiological follow-up and to reveal the period in which disease-modifying treatments are effective with serum parameters.

METHODS

One hundred eighty-six MS patients presented to our hospital between January 2016 and November 2021 and 94 age- and sex-matched healthy volunteers were recruited for our study. While 99 patients had active lesions on magnetic resonance imaging, 87 patients did not have any active lesions. Neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and monocyte/lymphocyte ratio (MLR) were determined. The SII (systemic immune inflammatory index) value was calculated according to the platelet X neutrophil/lymphocyte ratio formula.

RESULTS

NLR, MLR, PLR and SII values were found to be statistically significantly higher in MS patients than in the control group. The NLR, MLR, PLR and SII were higher in the active group with gadolonium than in the group without active lesions. In addition, the cutoff values that we can use to determine the presence of active lesions were 1.53, 0.18, 117.15, and 434.45 for NLR, MLR PLR and SII, respectively.

CONCLUSIONS

We found that all parameters correlated with radiological activity. In addition, we showed that we can detect the inflammatory period with high sensitivity and specificity with the cutoff value used for SII and PLR. Among these easily accessible and inexpensive evaluations, we concluded that SII, including the values in the PLR formula, can come to the fore.

Neurofilament light is associated with clinical outcome and hemorrhagic transformation in moderate to severe ischemic stroke

Background

Ischemic stroke is a leading cause of morbidity and mortality worldwide. One possible predictor is the use of biomarkers especially neurofilament light chain (NFL).

Objectives

To explore whether NFL could predict clinical outcome and hemorrhagic transformation in moderate to severe stroke.

Design

Single center prospective cohort study.

Methods

Fifty-one moderate to severe ischemic stroke patients were recruited. Blood NFL was obtained from patients at admission (First sample) and 24-96 hours later (Second sample). NFL was analyzed with the ultrasensitive single molecule array (Simoa). Later, we calculated incremental rate NFL (IRN) by changes in NFL per day from baseline. We evaluated National Institute of Health stroke scale (NIHSS), modified Rankins score (mRs), and the presence of hemorrhagic transformation (HT).

Results

IRN was found to be higher in patients with unfavorable outcome (7.12 vs 24.07, P = .04) as well as Second sample (49.06 vs 71.41, P = .011), while NFL First sample was not significant. IRN had a great correlation with mRS (r = .552, P < .001). Univariate logistic regression model showed OR of IRN and Second sample to be 1.081 (95% CI 1.016-1.149, P = .013) and 1.019 (1.002-1.037, P = .03), respectively. Multiple logistic regression model has shown to be significant. In receiver operating analysis, IRN, Second sample, combined IRN with NIHSS and combined Second sample with NIHSS showed AUC (.744, P = .004; 0.713, P = .01; 0.805, P < .001; 0.803, P < .001, respectively). For HT, First sample and Second sample had significant difference with HT (Z = 2.13, P = .033; Z = 2.487, P = .013, respectively).

Conclusion

NFL was found to correlate and predict clinical outcome. In addition, it was found to correlate with HT.

Maximizing treatment efficacy through patient stratification in neuropathic pain trials

Treatment of neuropathic pain remains inadequate despite the elucidation of multiple pathophysiological mechanisms and the development of promising therapeutic compounds. The lack of success in translating knowledge into clinical practice has discouraged pharmaceutical companies from investing in pain medicine; however, new patient stratification approaches could help bridge the translation gap and develop individualized therapeutic approaches. As we highlight in this article, subgrouping of patients according to sensory profiles and other baseline characteristics could aid the prediction of treatment success. Furthermore, novel outcome measures have been developed for patients with neuropathic pain. The extent to which sensory profiles and outcome measures can be employed in routine clinical practice and clinical trials and across distinct neuropathic pain aetiologies is yet to be determined. Improvements in animal models, drawing on our knowledge of human pain, and robust public-private partnerships will be needed to pave the way to innovative and effective pain medicine in the future.

Insight into Early Diagnosis of Multiple Sclerosis by Targeting Prognostic Biomarkers

Multiple sclerosis (MS) is a central nervous system (CNS) immune-mediated disease that mainly strikes young adults and leaves them disabled. MS is an autoimmune illness that causes the immune system to attack the brain and spinal cord. The myelin sheaths, which insulate the nerve fibers, are harmed by our own immune cells, and this interferes with brain signal transmission. Numbness, tingling, mood swings, memory problems, exhaustion, agony, vision problems, and/or paralysis are just a few of the symptoms. Despite technological advancements and significant research efforts in recent years, diagnosing MS can still be difficult. Each patient's MS is distinct due to a heterogeneous and complex pathophysiology with diverse types of disease courses. There is a pressing need to identify markers that will allow for more rapid and accurate diagnosis and prognosis assessments to choose the best course of treatment for each MS patient. The cerebrospinal fluid (CSF) is an excellent source of particular indicators associated with MS pathology. CSF contains molecules that represent pathological processes such as inflammation, cellular damage, and loss of blood-brain barrier integrity. Oligoclonal bands, neurofilaments, MS-specific miRNA, lncRNA, IgG-index, and anti-aquaporin 4 antibodies are all clinically utilised indicators for CSF in MS diagnosis. In recent years, a slew of new possible biomarkers have been presented. In this review, we look at what we know about CSF molecular markers and how they can aid in the diagnosis and differentiation of different MS forms and treatment options, and monitoring and predicting disease progression, therapy response, and consequences during such opportunistic infections.

[New neuroimaging methods in assessing the activity of neuroinflammation in multiple sclerosis]

The review presents current data on the use of positron emission tomography and single-photon emission computed tomography in multiple sclerosis (MS) to assess the activity of the pathological process, including neuroinflammation, demyelination, activation of microglia, neurodegeneration and local blood flow disorders. These methodologies are a new approach for studying the mechanisms of action and evaluating the clinical effect of disease modifying therapy of MS, especially those capable of penetrating into brain tissue. Among them, the most attention is attracted by cladribine tablets acting on the mechanism of immune reconstitution therapy, most likely with the modulation of immune reactions directly in the brain tissue.

Biomarkers of demyelination and axonal damage are decreased after autologous hematopoietic stem cell transplantation for multiple sclerosis

BACKGROUND

Autologous hematopoietic stem cell transplantation (aHSCT) has seen increased use for relapsing-remitting multiple sclerosis (RRMS) in recent years. It is considered one of the most effective treatments for RRMS and has been associated with improvement in disability and prolonged remission. This suggests that the tissue-injuring disease process may have been altered by aHSCT. To assess whether this hypothesis is correct, we performed a study of three commonly used cerebrospinal fluid biomarkers of tissue damage.

METHODS

In this single center study, 63 patients treated with aHSCT at Uppsala University Hospital between January 1st 2012 and January 31st 2019 were screened for participation. A control group consisting of volunteers without neurologic disease were included as a reference. Cerebrospinal fluid concentrations of neurofilament light (NFL), myelin basic protein (MBP) and glial acidic fibrillary protein (GFAp) were determined using ELISA and a multiplex proteomics platform from Meso Scale Discovery.

RESULTS

Forty-three patients with a mean age of 31 and a median follow-up time of 3.9 years were included. Their median baseline expanded disability status scale (EDSS) score was 3.5 and the annualized relapse rate in the year preceding aHSCT was 1.6. At baseline the proportion of patients with values above the upper limit of normal was 67% for NFL, 63% for MBP and 16% for GFAp. At 5-year follow-up, the proportion of patients with values above the upper limit of normal was 12% for NFL, 12% for MBP and 25% for GFAp. The mean concentration of NFL decreased from 920 pg/mL at baseline to 270 pg/mL at 5-year follow-up (p < 0.001); MBP decreased from 1500 to 680 pg/mL (p < 0.001); whereas the mean concentration of GFAp was unchanged.

CONCLUSION

In a majority of patients, biomarkers of demyelination and axonal damage reached normal values within five years from treatment with aHSCT.

Biofabrication of Multiplexed Electrochemical Immunosensors for Simultaneous Detection of Clinical Biomarkers in Complex Fluids

Simultaneous detection of multiple disease biomarkers in unprocessed whole blood is considered the gold standard for accurate clinical diagnosis. Here, this study reports the development of a 4-plex electrochemical (EC) immunosensor with on-chip negative control capable of detecting a range of biomarkers in small volumes (15 µL) of complex biological fluids, including serum, plasma, and whole blood. A framework for fabricating and optimizing multiplexed sandwich immunoassays is presented that is enabled by use of EC sensor chips coated with an ultra-selective, antifouling, and nanocomposite coating. Cyclic voltammetry evaluation of sensor performance is carried out by monitoring the local precipitation of an electroactive product generated by horseradish peroxidase linked to a secondary antibody. EC immunosensors demonstrate high sensitivity and specificity without background signal with a limit of detection in single-digit picogram per milliliter in multiple complex biological fluids. These multiplexed immunosensors enable the simultaneous detection of four different biomarkers in plasma and whole blood with excellent sensitivity and selectivity. This rapid and cost-effective biosensor platform can be further adapted for use with different high affinity probes for any biomarker, and thereby create for a new class of highly sensitive and specific multiplexed diagnostics.