Cerebrospinal Fluid pNF-H Research Articles

Parallel Cerebrospinal Fluid and Serum Temporal Profile Assessment of Axonal Injury Biomarkers Neurofilament-Light Chain and Phosphorylated Neurofilament-Heavy Chain: Associations With Patient Outcome in Moderate-Severe Traumatic Brain Injury.

Neurofilament-light chain (NF-L) and phosphorylated neurofilament-heavy chain (pNF-H) are axonal proteins that have been reported as potential diagnostic and prognostic biomarkers in traumatic brain injury (TBI). However, detailed temporal profiles for these proteins in blood, and interrelationships in the acute and chronic time periods post-TBI have not been established. Our objectives were: 1) to characterize acute-to-chronic serum NF-L and pNF-H profiles after moderate-severe TBI, as well as acute cerebrospinal fluid (CSF) levels; 2) to evaluate CSF and serum NF-L and pNF-H associations with each other; and 3) to assess biomarker associations with global patient outcome using both the Glasgow Outcome Scale-Extended (GOS-E) and Disability Rating Scale (DRS). In this multi-cohort study, we measured serum and CSF NF-L and pNF-H levels in samples collected from two clinical cohorts (University of Pittsburgh [UPITT] and Baylor College of Medicine [BCM]) of individuals with moderate-severe TBI. The UPITT cohort includes 279 subjects from an observational cohort study; we obtained serum (n = 277 unique subjects) and CSF (n = 95 unique subjects) daily for 1 week, and serum every 2 weeks for 6 months. The BCM cohort included 103 subjects from a previous randomized clinical trial of erythropoietin and blood transfusion threshold after severe TBI, which showed no effect on neurological outcome between treatment arms; serum (n = 99 unique subjects) and CSF (n = 54 unique subjects) NF-L and pNF-H levels were measured at least daily during Days (D) 0-10 post-injury. GOS-E and DRS were assessed at 6 months (both cohorts) and 12 months (UPITT cohort only). Results show serum NF-L and pNF-H gradually rise during the first 10 days and peak at D20-30 post-injury. In the UPITT cohort, acute (D0-6) NF-L and pNF-H levels correlate within CSF and serum (Spearman r = 0.44-0.48; p < 0.05). In the UPITT cohort, acute NF-L CSF and serum levels, as well as chronic (Months [M]2-6) serum NF-L levels, were higher among individuals with unfavorable GOS-E and worse DRS at 12 months (p < 0.05, all comparisons). In the BCM cohort, higher acute serum NF-L levels were also associated with unfavorable GOS-E. Higher pNF-H serum concentrations (D0-6 and M2-6), but not CSF pNF-H, were associated with unfavorable GOS-E and worse DRS (p < 0.05, all comparisons) in the UPITT cohort. Relationships between biomarker levels and favorable outcome persisted after controlling for age, sex, and Glasgow Coma Scale. This study shows for the first time that serum levels of NF-L and pNF-H peak at D20-30 post-TBI. Serum NF-L levels, and to a lesser extent pNF-H levels, are robustly associated with global patient outcomes and disability after moderate-severe TBI. Further studies on clinical utility as prognosis and treatment-response indicators are needed.

Phosphorylated neurofilament heavy chain in cerebrospinal fluid and plasma as a Nusinersen treatment response marker in childhood-onset SMA individuals from Serbia.

Biomarkers capable of reflecting disease onset and short- and long-term therapeutic effects in individuals with spinal muscular atrophy (SMA) are still an unmet need and phosphorylated neurofilament heavy chain (pNF-H) holds significant promise. We conducted a longitudinal prospective study to evaluate pNF-H levels in the cerebrospinal fluid (CSF) and plasma of 29 individuals with childhood-onset SMA treated with Nuinersen (SMA type 1: n = 6, 2: n = 17, 3: n = 6). pNF-H levels before and during treatment were compared with the levels of controls (n = 22), patients with Duchenne muscular dystrophy (n = 17), myotonic dystrophy type 1 (n = 11), untreated SMA individuals with chronic type 3 disease (n = 8), and children with presymptomatic SMA (n = 3). SMA type 1 showed the highest mean CSF pNF-H levels before treatment initiation. All Nusinersen-treated individuals (types 1, 2, and 3) showed significantly elevated mean baseline CSF pNF-H compared to controls, which inversely correlated with age at disease onset, age at first dose, disease duration and the initial CHOP INTEND result (SMA type 1 and 2). During 22 months of treatment, CSF pNF-H levels declined during loading doses, stabilizing at reduced levels from the initial maintenance dose in all individuals. Baseline plasma pNF-H levels in type 1 and 2 SMA were significantly increased compared to other cohorts and decreased notably in type 1 after 2 months of treatment and type 2 after 14 months. Conversely, SMA type 3, characterized by lower baseline pNF-H levels, did not show significant fluctuations in plasma pNF-H levels after 14 months of treatment. Our findings suggest that CSF pNF-H levels in untreated SMA individuals are significantly higher than in controls and that monitoring of CSF pNF-H levels may serve as an indicator of rapid short-term treatment response in childhood-onset SMA individuals, irrespective of the subtype of the disease, while also suggesting its potential for assessing long-term suppression of neurodegeneration. Plasma pNF-H may serve as an appropriate outcome measure for disease progression and/or response to treatment in types 1 and 2 but not in type 3. Presymptomatic infants with SMA may show elevated pNF-H levels, confirming early neuronal degeneration.

Diagnostic value of neurofilaments in differentiating motor neuron disease from multifocal motor neuropathy

ObjectiveTo evaluate the performance of serum neurofilament light chain (NfL) and cerebrospinal fluid (CSF) phosphorylated neurofilament heavy chain (pNfH) as diagnostic biomarkers for the differentiation between motor neuron disease (MND) and multifocal motor neuropathy (MMN).MethodsThis retrospective, monocentric study included 16 patients with MMN and 34 incident patients with MND. A subgroup of lower motor neuron (MN) dominant MND patients (n = 24) was analyzed separately. Serum NfL was measured using Ella automated immunoassay, and CSF pNfH was measured using enzyme-linked immunosorbent assay. Area under the curve (AUC), optimal cutoff values (Youden’s index), and correlations with demographic characteristics were calculated.ResultsNeurofilament concentrations were significantly higher in MND compared to MMN (p < 0.001), and serum NfL and CSF pNfH correlated strongly with each other (Spearman’s rho 0.68, p < 0.001). Serum NfL (AUC 0.946, sensitivity and specificity 94%) and CSF pNfH (AUC 0.937, sensitivity 90.0%, specificity 100%) performed excellent in differentiating MND from MMN. Optimal cutoff values were ≥ 44.15 pg/mL (serum NfL) and ≥ 715.5 pg/mL (CSF pNfH), respectively. Similar results were found when restricting the MND cohort to lower MN dominant patients. Only one MMN patient had serum NfL above the cutoff. Two MND patients presented with neurofilament concentrations below the cutoffs, both featuring a slowly progressive disease.ConclusionNeurofilaments are valuable supportive biomarkers for the differentiation between MND and MMN. Serum NfL and CSF pNfH perform similarly well and elevated neurofilaments in case of diagnostic uncertainty underpin MND diagnosis.

Effects of tofersen treatment in patients with SOD1-ALS in a “real-world” setting – a 12-month multicenter cohort study from the German early access program

In April 2023, the antisense oligonucleotide tofersen was approved by the U.S. Food and Drug Administration (FDA) for treatment of SOD1-amyotrophic lateral sclerosis (ALS), after a decrease of neurofilament light chain (NfL) levels had been demonstrated. Between 03/2022 and 04/2023, 24 patients with SOD1-ALS from ten German ALS reference centers were followed-up until the cut-off date for ALS functional rating scale revised (ALSFRS-R), progression rate (loss of ALSFRS-R/month), NfL, phosphorylated neurofilament heavy chain (pNfH) in cerebrospinal fluid (CSF), and adverse events. During the observation period, median ALSFRS-R decreased from 38.0 (IQR 32.0-42.0) to 35.0 (IQR 29.0-42.0), corresponding to a median progression rate of 0.11 (IQR-0.09 to 0.32) points of ALSFRS-R lost per month. Median serum NfL declined from 78.0pg/ml (IQR 37.0-147.0pg/ml; n=23) to 36.0pg/ml (IQR 22.0-65.0pg/ml; n=23; p=0.02), median pNfH in CSF from 2226pg/ml (IQR 1061-6138pg/ml; n=18) to 1151pg/ml (IQR 521-2360pg/ml; n=18; p=0.02). In the CSF, we detected a pleocytosis in 73% of patients (11of 15) and an intrathecal immunoglobulin synthesis (IgG, IgM, or IgA) in 9 out of 10 patients. Two drug-related serious adverse events were reported. Consistent with the VALOR study and its Open Label Extension (OLE), our results confirm a reduction of NfL serum levels, and moreover show a reduction of pNfH in CSF. The therapy was safe, as no persistent symptoms were observed. Pleocytosis and Ig synthesis in CSF with clinical symptoms related to myeloradiculitis in two patients, indicate the potential of an autoimmune reaction. No funding was received towards this study.

Comparison of neurofilament light and heavy chain in spinal muscular atrophy and amyotrophic lateral sclerosis: A pilot study.

Spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS) were two major motor neuron diseases with similar symptoms and poor outcomes. This study aimed to identify potential biomarkers in disease monitoring and differential diagnosis of adult SMA patients with sporadic ALS patients. This was a pilot study with ten adult SMA patients and ten ALS patients consecutively enrolled during hospitalization. Serum and cerebrospinal fluid (CSF) samples were collected for assessment of neurofilament light (NFL) and phosphorylated neurofilament heavy chain (pNFH). Serum creatine kinase (CK) and creatinine (Cr) were also compared between groups. The receiver operating characteristic (ROC) curves were used to identify differentiated values among ALS and SMA patients. Serum Cr, CSF NFL, and CSF pNFH levels of ALS patients were significantly higher than those of the adult SMA patients (p<.01). Serum CK and Cr were strongly correlated with baseline ALSFRS-R scores in SMA patients (p<.001). The ROC curves revealed an area under the curve (AUC) of 0.94 in serum Cr with a cut-off value of 44.5μmol/L (Sensitivity 90%, Specificity 90%). AUC from the ROC curve of CSF NFL and CSF pNFH were 1.0 and 0.84, with cut-off values of 1275 pg/mL and 0.395ng/mL, respectively (Sensitivity and Specificity of 100% and 100% in CSF NFL; Sensitivity and Specificity of 90% and 80% in CSF pNFH). CSF NFL and pNFH might be useful biomarkers for differential diagnosis of adult SMA and ALS.

Diagnostic utility of neurofilament markers for MND is limited in restricted disease phenotype and for differentiation from compressive myeloradiculopathies.

Misdiagnosis is frequent in early motor neuron disease (MND), typically compressive radiculopathy, or in patients with restricted MND phenotype. In this retrospective, single tertiary centre study, we measured levels of neurofilament light (NfL) and phosphorylated neurofilament heavy (p-NfH) chain in cerebrospinal fluid (CSF) and of p-NfH in serum with commercially available ELISA kits and assessed their respective diagnostic performance as a marker of MND. The entire study population (n = 164) comprised 71 MND patients, 30 patients with compressive myelo- or radiculopathy, and 63 disease controls (DC). Among MND patients, we specified subgroups with only lower motoneuron involvement (MND-LMN, n = 15) and with confounding nerve roots or spinal cord compression (MND-C, n = 18), representing clinical diagnostic pitfalls. MND-LMN displayed significantly lower CSF NfL (p = 0.003) and p-NFH (p = 0.017), but not serum p-NfH (p = 0.347) levels compared to other MND patients (n = 56). The discriminative ability (area under the curve-AUC) of both CSF Nfs towards all MND patients was comparable to each other but significantly higher than that of p-NfH in serum (ps < 0.001). AUC of both CSF Nfs between MND-LMN and DC and also between MND-C and myelo-/radiculopathies were reduced, as compared to AUC between other MND and DC or myelo-/radiculopathies, respectively. Our results suggest that both Nfs in CSF represent a reliable diagnostic marker in a general MND population, fulfilling Awaji criteria. As for diagnostic pitfalls, and also for p-NfH in serum, their discriminative ability and, therefore, clinical utility appears to be limited.

Biochemical and clinical biomarkers in adult SMA 3-4 patients treated with nusinersen for 22 months.

ObjectiveTo investigate biomarkers of disease progression in cerebrospinal fluid (CSF) and serum in adult patients with spinal muscular atrophy (SMA). Furthermore, we assess the clinical response to nusinersen treatment in adults with SMA over a longer follow‐up period than the previously reported 6–14 months.MethodsWe included 16 adults with SMA type 3–4 for nusinersen treatment over 22 months in this prospective study. We evaluated chitotriosidase‐1 (CHIT1) and chitinase‐3‐like protein 1 (YKL‐40) as neuroinflammatory biomarkers in CSF, and neurofilament light chain (NfL) and heavy chain (pNfH) as neurodegenerative markers in CSF and serum at baseline, month 6, 14 and 22, together with a wide range of clinical outcome measures.ResultsLevels of CHIT1 increased significantly (p = 0.048) throughout the 22‐month treatment period and pNfH decreased significantly (p = 0.022) in CSF, but both did not correlate with clinical outcome measures. YKL‐40 correlated strongly with neurofilaments in CSF (rho = 0.76) and decreased significantly (p = 0.037) in patients with improvements in the revised upper limb module (RULM). Finally, patients showed significant improvements in hand grip strength, hand motor function, medical research council (MRC) sum score, and peak expiratory flow (PEF) after 22 months of treatment.InterpretationYKL‐40 in CSF correlated with clinical improvements during nusinersen treatment. In contrast, CHIT1 and pNfH in CSF changed significantly during treatment but did not correlate with clinical outcomes. Finally, we demonstrated a sustained clinical effect of nusinersen treatment in adults after 22 months.

Serum and cerebrospinal fluid phosphorylated neurofilament heavy subunit as a marker of neuroaxonal damage in tick-borne encephalitis.

Extensive axonal and neuronal loss is the main cause of severe manifestations and poor outcomes in tick-borne encephalitis (TBE). Phosphorylated neurofilament heavy subunit (pNF-H) is an essential component of axons, and its detection in cerebrospinal fluid (CSF) or serum can indicate the degree of neuroaxonal damage. We examined the use of pNF-H as a biomarker of neuroaxonal injury in TBE. In 89 patients with acute TBE, we measured CSF levels of pNF-H and 3 other markers of brain injury (glial fibrillary acidic protein, S100B and ubiquitin C-terminal hydrolase L1) and compared the results to those for patients with meningitis of other aetiology and controls. Serum pNF-H levels were measured in 80 patients and compared with findings for 90 healthy blood donors. TBE patients had significantly (P<0.001) higher CSF pNF-H levels than controls as early as hospital admission. Serum pNF-H concentrations were significantly higher in samples from TBE patients collected at hospital discharge (P<0.0001) than in controls. TBE patients with the highest peak values of serum pNF-H, exceeding 10 000 pg ml-1, had a very severe disease course, with coma or tetraplegia. Patients requiring intensive care had significantly higher serum pNF-H levels than other TBE patients (P<0.01). Elevated serum pNF-H values were also observed in patients with incomplete recovery (P<0.05). Peak serum pNF-H levels correlated positively with the duration of hospitalization (P=0.005). Measurement of pNF-H levels in TBE patients might be useful for assessing disease severity and determining prognosis.

Neurofilament Levels in CSF and Serum in an Adult SMA Cohort Treated with Nusinersen.

To retrospectively evaluate the utility of serum and cerebrospinal fluid (CSF) levels of neurofilament light chain (NfL) and phosphorylated neurofilament heavy chain (pNfH) as biomarkers for spinal muscular atrophy (SMA) progression and response to nusinersen treatment. NfL and pNfH levels were quantified using single molecular array (SIMOA) in CSF of 33 adult SMA patients (SMN copy number 3-5) before and in response to nusinersen treatment. In 11 of the patients, blood serum samples were also collected. CSF NfL and pNfH from patients were compared to CSF Nfs from age-matched controls without neurological disease (n = 6). For patients, pearson correlation coefficients (r) were calculated to investigate associations between Nf levels and other functional outcome measures. Nf levels were similar between SMA and control adults and showed no change in response to nusinersen treatment in CSF or serum. Cross-sectional analyses showed an increase in CSF NfL and pNfH with age in patients (NfL p = 0.0013; pNfH p = 0.0035) and an increase in CSF NfL in controls (p = 0.002). In non-ambulatory patients, baseline serum pNfH showed a negative correlation with multiple strength and functional assessment metrics including Revised Upper Limb Module (r = -0.822, p = 0.04), upper extremity strength (r = -0.828, p = 0.042), lower extremity strength (r = -0.860, p = 0.028), and total strength (r = -0.870, p = 0.024). Nf levels did not change in response to nusinersen in adults with SMA and were not different from controls. In patients and controls, we detected an age-related increase in baseline CSF NfL and pNfH levels. Though some associations were identified, our results suggest Nf levels are not preditive or prognostic biomarkers in this population.

Neurofilament markers in serum and cerebrospinal fluid of patients with amyotrophic lateral sclerosis.

This study aims to determine the serum and cerebrospinal fluid (CSF) levels of neurofilament light chain (NFL) and phosphorylated neurofilament heavy chain (pNFH) in amyotrophic lateral sclerosis (ALS) patients, and to explore their feasibility as valid biomarkers for quantifying disease progression and predicting individual prognosis. 52 patients with ALS and 30 controls with noninflammatory neurological diseases were included. NFL and pNFH levels in serum and CSF were measured by enzyme‐linked immunosorbent assay. Our findings showed that serum and CSF levels of NFL and pNFH in ALS patients were significantly increased. These values were negatively correlated with disease duration (except CSF NFL with disease duration) and ALSFRS‐r score, and positively correlated with disease progression rate (DPR) and upper motor neuron (UMN) score, but did not correlate with bilateral median and ulnar nerve compound muscle action potential (cMAP) amplitudes (except a weak correlation between CSF NFL and cMAP amplitudes). The optimal cut‐off values with high sensitivity and specificity were obtained in ROC curve analysis to discriminate ALS from controls. Kaplan‐Meier survival curves illustrated that survival was significantly shorter for patients with higher neurofilament levels at diagnosis. The Cox proportional hazards regressions confirmed that NFL and pNFH were significant predictors of survival. Overall, NFL and pNFH in serum and CSF can be used as reliable biomarkers in ALS.

Neurofilaments can differentiate ALS subgroups and ALS from common diagnostic mimics

Delayed diagnosis and misdiagnosis are frequent in people with amyotrophic lateral sclerosis (ALS), the most common form of motor neuron disease (MND). Neurofilament light chain (NFL) and phosphorylated neurofilament heavy chain (pNFH) are elevated in ALS patients. We retrospectively quantified cerebrospinal fluid (CSF) NFL, CSF pNFH and plasma NFL in stored samples that were collected at the diagnostic work-up of ALS patients (n = 234), ALS mimics (n = 44) and controls (n = 9). We assessed the diagnostic performance, prognostication value and relationship to the site of onset and genotype. CSF NFL, CSF pNFH and plasma NFL levels were significantly increased in ALS patients compared to patients with neuropathies & myelopathies, patients with myopathies and controls. Furthermore, CSF pNFH and plasma NFL levels were significantly higher in ALS patients than in patients with other MNDs. Bulbar onset ALS patients had significantly higher plasma NFL levels than spinal onset ALS patients. ALS patients with C9orf72HRE mutations had significantly higher plasma NFL levels than patients with SOD1 mutations. Survival was negatively correlated with all three biomarkers. Receiver operating characteristics showed the highest area under the curve for CSF pNFH for differentiating ALS from ALS mimics and for plasma NFL for estimating ALS short and long survival. All three biomarkers have diagnostic value in differentiating ALS from clinically relevant ALS mimics. Plasma NFL levels can be used to differentiate between clinical and genetic ALS subgroups.

Comparative diagnosis interest of NfL and pNfH in CSF and plasma in a context of FTD-ALS spectrum.

The 'Frontotemporal dementia-Amyotrophic lateral sclerosis Spectrum' (FAS) encompasses different phenotypes, including cognitive disorders (frontotemporal dementia, FTD) and/or motor impairments (amyotrophic lateral sclerosis, ALS). The aim of this study was to apprehend the specific uses of neurofilaments light chain (NfL) and phosphorylated neurofilaments heavy chain (pNfH) in a context of FAS. First, NfL and pNfH were measured in 39 paired cerebrospinal fluid (CSF) and plasma samples of FAS and primary psychiatric disorders (PPD) patients, considered as controls. Secondly, additional plasma samples were included to examine a larger cohort of 81 samples composed of symptomatic FAS and PPD patients, presymptomatic and non-carrier relatives individuals. The measures were performed using Simoa technology. There was a positive correlation between CSF and plasma values for NfL (p < 0.0001) and for pNfH (p = 0.0036). NfL values were higher for all phenotypes of symptomatic FAS patients compared to PPD patients (p = 0.0016 in CSF; p = 0.0003 in plasma). On the contrary, pNfH values were solely increased in FAS patients exhibiting motor impairment. Unlike symptomatic FAS patients, presymptomatic cases had comparable concentrations with non-carrier individuals. NfL, but not pNfH, appeared to be useful in a context of differential diagnosis between FTD and psychiatric patients. Nevertheless, pNfH seem more specific for the diagnosis and follow-up of motor impairments. In each specific indication, measures in CSF and plasma will provide identical interpretations.

Phosphorylated Neurofilament Heavy Chain in the Cerebrospinal Fluid Is a Suitable Biomarker of Acute and Chronic Blast-Induced Traumatic Brain Injury.

Blast-induced traumatic brain injury (bTBI) has been documented as a significant concern for both military and civilian populations in response to the increased use of improvised explosive devices. Identifying biomarkers that could aid in the proper diagnosis and assessment of both acute and chronic bTBI is in urgent need since little progress has been made towards this goal. Addressing this knowledge gap is especially important in military veterans who are receiving assessment and care often years after their last blast exposure. Neuron-specific phosphorylated neurofilament heavy chain protein (pNFH) has been successfully evaluated as a reliable biomarker of different neurological disorders, as well as brain trauma resulting from contact sports and acute stages of brain injury of different origin. In the present study, we have evaluated the utility of pNFH levels measured in the cerebrospinal fluid (CSF) as an acute and chronic biomarker of brain injury resulting from single and tightly coupled repeated blast exposures using experimental rats. The pNFH levels increased at 24 h, returned to normal levels at 1 month, but increased again at 6 months and 1 year post-blast exposures. No significant changes were observed between single and repeated blast-exposed groups. To determine whether the observed increase of pNFH in CSF corresponded with its levels in the brain, we performed fluorescence immunohistochemistry in different brain regions at the four time-points evaluated. We observed decreased pNFH levels in those brain areas at 24 h, 6 months, and 1 year. The results suggest that blast exposure causes axonal degeneration at acute and chronic stages resulting in the release of pNFH, the abundant neuronal cytoskeletal protein. Moreover, the changes in pNFH levels in the CSF negatively correlated with the neurobehavioral functions in the rats, reinforcing suggestions that CSF levels of pNFH can be a suitable biomarker of bTBI.

Serum and cerebrospinal fluid phosphorylated neurofilament heavy protein concentrations in equine neurodegenerative diseases.

Currently, there is little information regarding the concentrations of phosphorylated neurofilament heavy protein (pNfH) in the serum and cerebrospinal fluid (CSF) of horses with neurodegenerative diseases. Specifically, pNfH concentrations have not yet been evaluated in horses with equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM). To determine pNfH concentrations using a commercial enzyme-linked immunosorbent assay (ELISA) in serum and CSF from control horses and horses with eNAD/EDM, cervical vertebral compressive myelopathy (CVCM) and Shivers. Case-control study using biobanked samples from diseased horses and prospective or biobanked samples from control horses. The pNfH ELISA was performed on samples from horses diagnosed with eNAD/EDM (n=64), CVCM (n=26) and Shivers (n=9) and 51 neurologically normal control horses. Median and 95% confidence interval (CI) serum pNfH concentrations in control, CVCM, and eNAD/EDM horses were 0.08ng/mL (0.07-0.15), 0.07ng/mL (0.07-0.15) and 0.07ng/mL (0.07-1.13), respectively. Serum pNfH concentrations were below the limit of detection (<0.07ng/mL) for all Shivers horses. CSF pNfH concentrations in control, CVCM-, eNAD/EDM- and Shivers-affected horses were 1.26ng/mL (1.06-1.5), 3.07ng/mL (1.15-29.9), 1.78ng/mL (1.5-2.28) and 1.39ng/mL (0.74-3.89), respectively. CSF pNfH concentrations were significantly higher in CVCM (P=.001) and eNAD/EDM (P =.01) affected horses compared to control horses. Serum pNfH concentrations >1ng/mL were significantly associated with eNAD/EDM (P=.01) with only 12% sensitivity but 99% specificity. CSF pNfH concentrations >3ng/mL were significantly associated with CVCM (P=.0002), with 50% sensitivity and 86% specificity. A limited number of control horses tested were <1 year of age. Serum pNfH concentrations are specifically increased (>1ng/mL) in some horses with eNAD/EDM. Increased CSF pNfH concentrations (>3ng/mL) can be observed with eNAD/EDM or CVCM.

Correlations between macrophage/microglial activation marker sTREM-2 and measures of T-cell activation, neuroaxonal damage and disease severity in multiple sclerosis.

BackgroundSoluble triggering receptor expressed on myeloid cells-2 (sTREM-2) is a marker of macrophage and microglial activation and is increased in the cerebrospinal fluid (CSF) in multiple sclerosis (MS).ObjectiveTo determine the relationships among sTREM-2, T cell activation, neuroaxonal damage and clinical features of MS.MethodsEnzyme-linked immunosorbent assays were used to measure the levels of sTREM-2, soluble CD27 (sCD27, a marker of T cell activation), neurofilament light chain (NfL) and phosphorylated neurofilament heavy chain (pNfH) in the CSF of 42 patients with MS (including nine with clinically isolated syndrome) and 15 patients with other neurological diseases (OND) and in the serum of 164 patients with MS, 87 patients with OND and 62 healthy controls.ResultssTREM-2 was significantly elevated in the CSF (p = 0.012), but not in the serum, in MS compared to OND. In MS, CSF sTREM-2 correlated positively with CSF sCD27 (p = 0.005), CSF NfL (p = 0.0001), CSF pNfH (p = 0.0006), Expanded Disability Status Scale (EDSS) score (p = 0.0079) and MS Severity Score (MSSS) (p = 0.0006).ConclusionIn MS the level of sTREM-2 in the CSF is related to measures of T cell activation (sCD27), neuroaxonal damage (NfL and pNfH), disability (EDSS) and disease severity (MSSS).

Cerebrospinal Fluid Level of Phosphorylated Neurofilament Heavy Chain is Higher in Converting Clinically Isolated Syndrome and Correlates with CAMP Response Element-Binding Protein Concentration

Introduction: Prevision of conversion from clinically isolated syndrome (CIS) to multiple sclerosis (MS) is required to avoid unnecessary use of immunomodulating agents and to recognize patients with high disease activity. Our aim was to evaluate the value of phosphorylated neurofilament heavy chain (pNFH, a marker for neuroaxonal degeneration) and Cyclic adenosine monophosphate response element-binding protein (cAMP response element-binding protein [CREB], a marker for neuroregeneration) levels in the prediction of conversion from CIS to MS. Methods: Twenty-three consecutively recruited treatment-naïve CIS patients were followed for 36 months. pNFH and CREB levels were measured in the first episode cerebrospinal fluid (CSF) and the serum of 12 converting (CIS-MS) and 11 nonconverting CIS patients (CIS-CIS) by enzyme-linked immunosorbent assay. Results: Baseline CSF but not serum samples of CIS-CIS patients displayed significantly lower pNFH levels compared to patients with CIS-MS. The analysis of receiver operating characteristic curve presented a high specificity for the prediction of MS conversion for the CSF pNFH cut-off level of 730.9 pg/ml. CSF pNFH levels significantly correlated with serum and CSF CREB levels. Higher baseline CSF pNFH and CREB levels were associated with more rapid progression to MS or increased disability scores. Conclusion: CSF pNFH measurement may potentially determine MS patients with unfavorable clinical progression after the first attack. pNFH and CREB appear to be increased in parallel in CSF of CIS patients with higher disease activity. These results suggest that neurofilaments are not only indicators of axonal degeneration but also partly a marker of neuronal differentiation and new axon regeneration mediated by CREB signaling pathway.

CSF Neurofilament-H Levels as a Potential Prognostic Marker in Patients of Guillain- Barré Syndrome- A Cohort Study

Introduction: The prognosis of Guillain-Barré Syndrome (GBS) at an early stage with explicit biomarkers is critical to distinguish patients with possibility of poor recovery. Cerebrospinal Fluid (CSF) serves as an impending source for biomarkers that portrays the exact biochemical changes. Aim: To find out if there is any prognostic value of high CSF phosphorylated Neurofilament Heavy subunit (pNf-H) levels, measured during first two weeks of onset of GBS, as assessed by the level of disability at six months after the onset of GBS. Materials and Methods: The cohort study was conducted in the Department of Neurology and Department of Immunology and Molecular Medicine, at the Sher-I-Kashmir Institute of Medical Sciences, Soura, Srinagar, Jammu and Kashmir, India, over a period of two years from August 2015 to August 2017. Sixty two patients who satisfied the required diagnostic standards for GBS (study group) and 35 patients with tension-type headache (control group) were selected for the study. After clinical and electrophysiological assessment, CSF samples were collected. A commercially available sandwich enzyme immunoassay kit, manufactured by BioVendor-Laboratorní medicína (Czech Republic), was used for measuring human pNf-H quantitatively. Results: Mean CSF pNf-H level in patients with good outcome was 325.3 pg/mL whereas, in patients with poor outcome it was 3655.2 pg/mL. CSF pNf-H levels were found to be suggestively higher in GBS patients with poor outcome as compared to those with good outcome. Only eight patients in good outcome group had pathologically high CSF Nf-H levels whereas 10 patients in poor outcome group had CSF Nf-H levels ≤730 pg/mL. The odds ratio was 17.1 (95% Confidence Interval (CI) 3.83-76.29). Thus, high CSF Nf-H levels on admission predicted poor outcome in GBS (p-value &lt;0.001). Moderate degree of positive correlation was found between CSF Nf-H levels and outcome (F score) at six months (R=0.684; p-value &lt;0.001). Conclusion: It can be determined that higher values of CSF pNf-H in GBS (acute stage), could serve as a predictive marker indicative of poor prognosis.

Cerebrospinal fluid levels of GFAP and pNF-H are elevated in patients with chronic spinal cord injury and neurological deterioration

BackgroundYears after a traumatic spinal cord injury (SCI), a subset of patients may develop progressive clinical deterioration due to intradural scar formation and spinal cord tethering, with or without an associated syringomyelia. Meningitis, intradural hemorrhages, or intradural tumor surgery may also trigger glial scar formation and spinal cord tethering, leading to neurological worsening. Surgery is the treatment of choice in these chronic SCI patients.ObjectiveWe hypothesized that cerebrospinal fluid (CSF) and plasma biomarkers could track ongoing neuronal loss and scar formation in patients with spinal cord tethering and are associated with clinical symptoms.MethodsWe prospectively enrolled 12 patients with spinal cord tethering and measured glial fibrillary acidic protein (GFAP), ubiquitin C-terminal hydrolase L1 (UCH-L1), and phosphorylated Neurofilament-heavy (pNF-H) in CSF and blood. Seven patients with benign lumbar intradural tumors and 7 patients with cervical radiculopathy without spinal cord involvement served as controls.ResultsAll evaluated biomarker levels were markedly higher in CSF than in plasma, without any correlation between the two compartments. When compared with radiculopathy controls, CSF GFAP and pNF-H levels were higher in patients with spinal cord tethering (p ≤ 0.05). In contrast, CSF UCH-L1 levels were not altered in chronic SCI patients when compared with either control groups.ConclusionsThe present findings suggest that in patients with spinal cord tethering, CSF GFAP and pNF-H levels might reflect ongoing scar formation and neuronal injury potentially responsible for progressive neurological deterioration.

Neurofilament Proteins as Prognostic Biomarkers in Neurological Disorders.

Neurofilaments: light, medium, and heavy (abbreviated as NF-L, NF-M, and NF-H, respectively), which belong to Type IV intermediate filament family (IF), are neuron-specific cytoskeletal components. Neurofilaments are axonal structural components and integral components of synapses, which are important for neuronal electric signal transmissions along the axons and post-translational modification. Abnormal assembly of neurofilaments is found in several human neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), infantile spinal muscular atrophy (SMA), and hereditary sensory-motor neuropathy (HSMN). In addition, those pathological neurofilament accumulations are known in α-synuclein in Parkinson's disease (PD), Aβ and tau in Alzheimer's disease (AD), polyglutamine in CAG trinucleotide repeat disorders, superoxide dismutase 1 (SOD1), TAR DNA-binding protein 43 (TDP43), neuronal FUS proteins, optineurin (OPTN), ubiquilin 2 (UBQLN2), and dipeptide repeat protein (DRP) in amyotrophic lateral sclerosis (ALS). When axon damage occurs in central nervous disorders, neurofilament proteins are released and delivered into cerebrospinal fluid (CSF), which are then circulated into blood. New quantitative analyses and assay techniques are well-developed for the detection of neurofilament proteins, particularly NF-L and the phosphorylated NF-H (pNF-H) in CSF and serum. This review discusses the potential of using peripheral blood NF quantities and evaluating the severity of damage in the nervous system. Intermediate filaments could be promising biomarkers for evaluating disease progression in different nervous system disorders.

Neurofilaments in pre-symptomatic ALS and the impact of genotype

Objective. To evaluate serum and cerebrospinal fluid (CSF) levels of phosphorylated neurofilament heavy (pNfH), and to compare these to levels of neurofilament light (NfL), as biomarkers of pre-symptomatic ALS. Design. The study population includes 34 controls, 79 individuals at-risk for ALS, 22 ALS patients, and 14 phenoconverters. At-risk individuals are enrolled through Pre-Symptomatic Familial ALS (Pre-fALS), a longitudinal natural history and biomarker study of individuals who are carriers of any ALS-associated gene mutation, but who demonstrate no clinical evidence of disease at the time of enrollment. pNfH and NfL in serum and CSF were quantified using established enzyme-linked immunosorbent assays. Results. There is a longitudinal increase in serum pNfH in advance of the emergence of clinically manifest ALS. A similar pattern is observed for NfL, but with the absolute levels also frequently exceeding a normative threshold. Although CSF data are more sparse, similar patterns are observed for both neurofilaments, with absolute levels exceeding a normative threshold prior to phenoconversion. In serum, these changes are observed in the 6–12 months prior to disease among SOD1 A4V mutation carriers, and as far back as 2 and 3.5 years, respectively, in individuals with a FUS c.521del6 mutation and a C9ORF72 hexanucleotide repeat expansion. Conclusions. Serum and CSF pNfH increase prior to phenoconversion. In CSF, the temporal course of these changes is similar to NfL. In serum, however, pNfH is less sensitive to pre-symptomatic disease than NfL. The duration of pre-symptomatic disease, as defined by changes in neurofilaments, may vary depending on underlying genotype.