Serum Glial Fibrillary Acidic Protein and Neurofilament Light Chain Levels Reflect Different Mechanisms of Disease Progression under B-Cell Depleting Treatment in Multiple Sclerosis.

OBJECTIVE: To investigate the longitudinal dynamics of serum glial fibrillary acidic protein (sGFAP) and serum neurofilament light chain (sNfL) levels in people with multiple sclerosis (pwMS) under B-cell depleting therapy (BCDT) and their capacity to prognosticate future progression independent of relapse activity (PIRA) events. METHODS: A total of 362 pwMS (1,480 samples) starting BCDT in the Swiss Multiple Sclerosis (MS) Cohort were included. sGFAP levels in 2,861 control persons (4,943 samples) provided normative data to calculate adjusted Z scores. RESULTS: Elevated sGFAP levels (Z score >1) at 1 year were associated with a higher hazard for PIRA (hazard ratio [HR]: 1.80 [95% CI: 1.17-2.78]; p = 0.0079) than elevated sNfL levels (HR, 1.45 [0.95-2.24], p = 0.0886) in a combined model. Independent of PIRA events, sGFAP levels longitudinally increased by 0.49 Z score units per 10 years follow-up (estimate, 0.49 [0.29, 0.69], p < 0.0001). In patients experiencing PIRA, sGFAP Z scores were 0.52 Z score units higher versus stable patients (0.52 [0.22, 0.83], p = 0.0009). Different sNfL Z score trajectories were found in pwMS with versus without PIRA (interaction p = 0.0028), with an average decrease of 0.92 Z score units per 10 years observed without PIRA (-0.92 [-1.23, -0.60], p < 0.0001), whereas levels in patients with PIRA remained high. INTERPRETATION: Elevated sGFAP and lack of drop in sNfL after BCDT start are associated with increased risk of future PIRA. These findings provide a rationale for combined monitoring of sNfL and sGFAP in pwMS starting BCDT to predict the risk of PIRA, and to use sGFAP as an outcome in clinical trials aiming to impact on MS progressive disease biology. ANN NEUROL 2024.

Long-term analysis of infections and associated risk factors in patients with multiple sclerosis treated with ocrelizumab: pooled analysis of 13 interventional clinical trials.

Background: Patients with multiple sclerosis (PwMS) have an increased risk of infections. Objectives: To characterize incidence, clinical characteristics, outcomes and risk factors of infections, and serious infections (SIs) in ocrelizumab (OCR)-treated PwMS. Design: Post-hoc analysis of pooled data from 6155 patients in 13 clinical trials. Methods: Descriptive analyses of clinical characteristics and outcomes were reported over ⩽14 years. A Poisson Generalized Estimating Equation model was constructed to examine risk factors in a subgroup of patients with longer exposure to OCR (n = 2092). Results: Over a median (max) treatment period of 3.7 (13.9) years, 420/6155 patients (6.8%) experienced 583 SIs, excluding coronavirus disease 2019. Incidence rates in relapsing multiple sclerosis (RMS; 1.50 per 100 patient years [95% confidence interval (CI): 1.34-1.68]) and progressive multiple sclerosis (PMS; 3.70 [95% CI: 3.27-4.17]) remained stable over this period. Lower respiratory tract, urinary tract, abdominal and gastrointestinal, and skin infections were the most commonly reported SIs. Most SIs (~90%) resolved, and treatment with OCR was continued in >80% of cases. The presence of 1 or ⩾2 comorbidities (rate ratio = 1.66, 2.73, respectively), recent relapse activity (2.06), and Expanded Disability Status Scale (EDSS) score ⩾6.0 (2.02) were significant risk factors for SIs in patients with RMS treated over a median (max) period of 8.3 (11.2) years. In patients with primary PMS treated over a median (max) period of 7.1 (11.8) years, an EDSS score ⩾6.0 was associated with the greatest risk of SIs, a 4-fold increase (rate ratio, 4.31), followed by abnormal immunoglobulin (Ig)M levels (1.89), the presence of ⩾2 comorbidities (1.80), and having overweight/obesity (1.46). Time on OCR and abnormal IgG levels were not significantly associated with an increased SI risk. Conclusion: Continuous long-term treatment with OCR is associated with a manageable infection risk profile. Optimal disease control and addressing modifiable risk factors may reduce the risk of infections.

Is continued treatment with ocrelizumab associated with a higher risk of infections and serious infections in patients with multiple sclerosis? Patients with multiple sclerosis (PwMS) are at an increased risk of infections compared with the general population. Infections are also among the most frequently reported side effect in PwMS treated with ocrelizumab. Initial analyses have shown that serious infection (SI) rates in PwMS treated with ocrelizumab were stable over 6 years, but there is concern that this rate may increase with continued treatment. This study aimed to describe infections and SIs in PwMS treated with ocrelizumab and look into factors that increase patients' susceptibility to infections. We analyzed the largest population of PwMS ever treated with ocrelizumab, including 6155 patients from 13 clinical trials. Some of these patients received ocrelizumab for as long as 14 years. Approximately 7 out of every 100 patients experienced SIs, excluding COVID-19 infections, with no increase in yearly rates of SIs over time. Pneumonia and urinary tract infections were the most common SIs. Almost all patients recovered from their infections (>9 out of 10 cases), and continued treatment with ocrelizumab (>8 out of 10 cases). When looking at factors that made PwMS more prone to SIs, we found that patients with relapsing MS had an increased risk if they had experienced recent MS relapses, severe walking difficulties, or other health conditions like diabetes and bladder problems. Patients with primary progressive MS (PPMS) with severe walking difficulties were four times more likely to have SIs. Having other health conditions like heart or bladder problems, low levels of immunoglobulin M, or excess weight also increased the risk of SIs in patients with PPMS. In conclusion, continued treatment with ocrelizumab did not increase the risk of SIs, and most of those infections resolved without stopping ocrelizumab treatment. Addressing certain health conditions and achieving a good control of the MS disease may help to reduce the risk of SIs.

Targeting cytokine networks in neuroinflammatory diseases.

In neuroinflammatory diseases, systemic (blood-borne) leukocytes invade the central nervous system (CNS) and lead to tissue damage. A causal relationship between neuroinflammatory diseases and dysregulated cytokine networks is well established across several preclinical models. Cytokine dysregulation is also observed as an inadvertent effect of cancer immunotherapy, where it often leads to neuroinflammation. Neuroinflammatory diseases can be separated into those in which a pathogen is at the centre of the immune response and those of largely unknown aetiology. Here, we discuss the pathophysiology, cytokine networks and therapeutic landscape of 'sterile' neuroinflammatory diseases such as multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), neurosarcoidosis and immune effector cell-associated neurotoxicity syndrome (ICANS) triggered by cancer immunotherapy. Despite successes in targeting cytokine networks in preclinical models of neuroinflammation, the clinical translation of targeting cytokines and their receptors has shown mixed and often paradoxical responses.

Case report: Concurrent MOG antibody-associated disease and latent infections in two patients.

Objectives: Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is frequently preceded by infections. The underlying pathomechanism, however, remains poorly understood. Here, we present the clinical data of two MOGAD patients with concurrent syphilis infection and investigate the reactivity of patient-derived antibodies to MOG and Treponema pallidum (T. pallidum). Methods: Longitudinal serum samples and soluble immunoglobulins in single B cell supernatants were measured for MOG reactivity by a live cell-based assay. Reactivity against T. pallidum was assessed by enzyme-linked immunosorbent assay. Results: The two patients presented MOGAD and concurrent latent syphilis infection, manifesting as cervical myelitis and unilateral optic neuritis, respectively. The first patient had been living with HIV on antiretroviral therapy, and the second was concomitantly diagnosed with chronic hepatitis B infection. Upon screening of B cell supernatants, we identified reactivity to MOG or T. pallidum. Notably, one B cell showed reactivity to both antigens. Discussion: The coexistence of MOGAD diagnoses and latent syphilis, alongside the identification of antibody reactivity to MOG and T. pallidum, underscores the potential pathomechanistic link between syphilis infection and subsequent autoimmune neuroinflammation. Cross-reactivity between MOG and T. pallidum antibodies remains to be validated on a molecular level, and further characterization of infectious triggers associated with MOGAD is needed.

MultiSCRIPT-Cycle 1-a pragmatic trial embedded within the Swiss Multiple Sclerosis Cohort (SMSC) on neurofilament light chain monitoring to inform personalized treatment decisions in multiple sclerosis: a study protocol for a randomized clinical trial.

BACKGROUND: Treatment decisions for persons with relapsing-remitting multiple sclerosis (RRMS) rely on clinical and radiological disease activity, the benefit-harm profile of drug therapy, and preferences of patients and physicians. However, there is limited evidence to support evidence-based personalized decision-making on how to adapt disease-modifying therapy treatments targeting no evidence of disease activity, while achieving better patient-relevant outcomes, fewer adverse events, and improved care. Serum neurofilament light chain (sNfL) is a sensitive measure of disease activity that captures and prognosticates disease worsening in RRMS. sNfL might therefore be instrumental for a patient-tailored treatment adaptation. We aim to assess whether 6-monthly sNfL monitoring in addition to usual care improves patient-relevant outcomes compared to usual care alone. METHODS: Pragmatic multicenter, 1:1 randomized, platform trial embedded in the Swiss Multiple Sclerosis Cohort (SMSC). All patients with RRMS in the SMSC for ≥ 1 year are eligible. We plan to include 915 patients with RRMS, randomly allocated to two groups with different care strategies, one of them new (group A) and one of them usual care (group B). In group A, 6-monthly monitoring of sNfL will together with information on relapses, disability, and magnetic resonance imaging (MRI) inform personalized treatment decisions (e.g., escalation or de-escalation) supported by pre-specified algorithms. In group B, patients will receive usual care with their usual 6- or 12-monthly visits. Two primary outcomes will be used: (1) evidence of disease activity (EDA3: occurrence of relapses, disability worsening, or MRI activity) and (2) quality of life (MQoL-54) using 24-month follow-up. The new treatment strategy with sNfL will be considered superior to usual care if either more patients have no EDA3, or their health-related quality of life increases. Data collection will be embedded within the SMSC using established trial-level quality procedures. DISCUSSION: MultiSCRIPT aims to be a platform where research and care are optimally combined to generate evidence to inform personalized decision-making in usual care. This approach aims to foster better personalized treatment and care strategies, at low cost and with rapid translation to clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov NCT06095271. Registered on October 23, 2023.

Contrast-Enhancing Lesion Segmentation in Multiple Sclerosis: A Deep Learning Approach Validated in a Multicentric Cohort.

The detection of contrast-enhancing lesions (CELs) is fundamental for the diagnosis and monitoring of patients with multiple sclerosis (MS). This task is time-consuming and suffers from high intra- and inter-rater variability in clinical practice. However, only a few studies proposed automatic approaches for CEL detection. This study aimed to develop a deep learning model that automatically detects and segments CELs in clinical Magnetic Resonance Imaging (MRI) scans. A 3D UNet-based network was trained with clinical MRI from the Swiss Multiple Sclerosis Cohort. The dataset comprised 372 scans from 280 MS patients: 162 showed at least one CEL, while 118 showed no CELs. The input dataset consisted of T1-weighted before and after gadolinium injection, and FLuid Attenuated Inversion Recovery images. The sampling strategy was based on a white matter lesion mask to confirm the existence of real contrast-enhancing lesions. To overcome the dataset imbalance, a weighted loss function was implemented. The Dice Score Coefficient and True Positive and False Positive Rates were 0.76, 0.93, and 0.02, respectively. Based on these results, the model developed in this study might well be considered for clinical decision support.

Presentation and Outcome in S1P-RM and Natalizumab-Associated Progressive Multifocal Leukoencephalopathy: A Multicenter Cohort Study.

BACKGROUND AND OBJECTIVES: Progressive multifocal leukoencephalopathy (PML) is a severe neurologic disease resulting from JC virus reactivation in immunocompromised patients. Certain multiple sclerosis (MS) disease-modifying therapies (DMTs) are associated with PML risk, such as natalizumab and, more rarely, sphingosine-1-phosphate receptor modulators (S1P-RMs). Although natalizumab-associated PML is well documented, information on S1P-RM-associated PML is limited. The aim of this study is to compare clinical presentations and outcomes between the 2 groups. METHODS: A retrospective multicenter cohort study included patients with PML from 2009 to 2022 treated with S1P-RMs or natalizumab. Data on clinical and radiologic presentation, outcomes, immune reconstitution inflammatory syndrome (IRIS), survival, disability (using the modified Ranking scale-mRS), and MS relapses post-PML were analyzed. RESULTS: Of 88 patients, 84 were analyzed (20 S1P-RM, 64 natalizumab). S1P-RM-associated PML was diagnosed in older patients (median age 52 vs 44 years, p < 0.001) and after longer treatment duration (median 63.9 vs 40 months, p < 0.001). Similarly, S1P-RM patients were more prone to show symptoms at diagnosis (100 vs 80.6%, p = 0.035), had more disseminated lesions (80% vs 34.9%, p = 0.002), and had higher gadolinium enhancement (65% vs 39.1%, p = 0.042). Natalizumab patients had a higher IRIS development rate (OR: 8.3 [1.92-33.3]). Overall, the outcome (mRS) at 12 months was similar in the 2 groups (OR: 0.81 [0.32-2.0]). Yet, post-treatment MS activity was higher in S1P-RM cases (OR: 5.7 [1.4-22.2]). DISCUSSION: S1P-RM-associated PML shows reduced IRIS risk but higher post-treatment MS activity. Clinicians should tailor post-PML treatment based on pre-PML medication.

Escalating to medium- versus high-efficacy disease modifying therapy after low-efficacy treatment in relapsing remitting multiple sclerosis.

BACKGROUND: In patients with relapsing remitting multiple sclerosis (RRMS) on low-efficacy disease modifying therapies (DMT), the optimal strategy on how to escalate treatment once needed, remains unknown. METHODS: We studied RRMS patients on low-efficacy DMTs listed in the Swiss National Treatment Registry, who underwent escalation to either medium- or high-efficacy DMTs. Propensity score-based matching was applied using 12 clinically relevant variables. Both groups were also separately matched with control subjects who did not escalate therapy. Time to relapse and to disability worsening were evaluated using Cox proportional hazard models. RESULTS: Of 1037 eligible patients, we 1:1 matched 450 MS patients who switched from low-efficacy to medium-efficacy (n = 225; 76.0% females, aged 42.4 ± 9.9 years [mean ± SD], median EDSS 3.0 [IQR 2-4]) or high-efficacy DMTs (n = 225; 72.4% females, aged 42.2 ± 10.6 years, median EDSS 3.0 [IQR 2-4]). Escalation to high-efficacy DMTs was associated with lower hazards of relapses than medium-efficacy DMTs (HR = 0.67, 95% CI 0.47-0.95, p = .027) or control subjects (HR = 0.61, 95% CI 0.44-0.84, p = .003). By contrast, escalation from low to medium-efficacy DMTs did not alter the hazard for relapses when compared to controls (i.e. patients on low-efficacy DMT who did not escalate DMT during follow-up) CONCLUSION: Our nationwide registry analysis suggests that, once escalation from a low-efficacy DMT is indicated, switching directly to a high-efficacy treatment is superior to a stepwise escalation starting with a moderate-efficacy treatment.

Complement Activation Is Associated With Disease Severity in Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Histopathologic studies have identified immunoglobulin (Ig) deposition and complement activation as contributors of CNS tissue damage in multiple sclerosis (MS). Intrathecal IgM synthesis is associated with higher MS disease activity and severity, and IgM is the strongest complement-activating immunoglobulin. In this study, we investigated whether complement components (CCs) and complement activation products (CAPs) are increased in persons with MS, especially in those with an intrathecal IgM synthesis, and whether they are associated with disease severity and progression. METHODS: CC and CAP levels were quantified in plasma and CSF of 112 patients with clinically isolated syndrome (CIS), 127 patients with MS (90 relapsing-remitting, 14 primary progressive, and 23 secondary progressive), 31 inflammatory neurologic disease, and 44 symptomatic controls from the Basel CSF databank study. Patients with CIS/MS were followed in the Swiss MS cohort study (median 6.3 years). Levels of CC/CAP between diagnosis groups were compared; in CIS/MS, associations of CC/CAP levels with intrathecal Ig synthesis, baseline Expanded Disability Status Scale (EDSS) scores, MS Severity Score (MSSS), and neurofilament light chain (NfL) levels were investigated by linear regression, adjusted for age, sex, and albumin quotient. RESULTS: CSF (but not plasma) levels of C3a, C4a, Ba, and Bb were increased in patients with CIS/MS, being most pronounced in those with an additional intrathecal IgM production. In CIS, doubling of C3a and C4a in CSF was associated with 0.31 (CI 0.06-0.56; p = 0.016) and 0.32 (0.02-0.62; p = 0.041) increased EDSS scores at lumbar puncture. Similarly, doubling of C3a and Ba in CIS/MS was associated with 0.61 (0.19-1.03; p < 0.01) and 0.74 (0.18-1.31; p = 0.016) increased future MSSS. In CIS/MS, CSF levels of C3a, C4a, Ba, and Bb were associated with increased CSF NfL levels, e.g., doubling of C3a was associated with an increase of 58% (Est. 1.58; CI 1.37-1.81; p < 0.0001). DISCUSSION: CNS-compartmentalized activation of the classical and alternative pathways of complement is increased in CIS/MS and associated with the presence of an intrathecal IgM production. Increased complement activation within the CSF correlates with EDSS, future MSSS, and NfL levels, supporting the concept that complement activation contributes to MS pathology and disease progression. Complement inhibition should be explored as therapeutic target to attenuate disease severity and progression in MS.

Association of Spinal Cord Atrophy and Brain Paramagnetic Rim Lesions With Progression Independent of Relapse Activity in People With MS.

BACKGROUND AND OBJECTIVES: Progression independent of relapse activity (PIRA) is a crucial determinant of overall disability accumulation in multiple sclerosis (MS). Accelerated brain atrophy has been shown in patients experiencing PIRA. In this study, we assessed the relation between PIRA and neurodegenerative processes reflected by (1) longitudinal spinal cord atrophy and (2) brain paramagnetic rim lesions (PRLs). Besides, the same relationship was investigated in progressive MS (PMS). Last, we explored the value of cross-sectional brain and spinal cord volumetric measurements in predicting PIRA. METHODS: From an ongoing multicentric cohort study, we selected patients with MS with (1) availability of a susceptibility-based MRI scan and (2) regular clinical and conventional MRI follow-up in the 4 years before the susceptibility-based MRI. Comparisons in spinal cord atrophy rates (explored with linear mixed-effect models) and PRL count (explored with negative binomial regression models) were performed between: (1) relapsing-remitting (RRMS) and PMS phenotypes and (2) patients experiencing PIRA and patients without confirmed disability accumulation (CDA) during follow-up (both considering the entire cohort and the subgroup of patients with RRMS). Associations between baseline MRI volumetric measurements and time to PIRA were explored with multivariable Cox regression analyses. RESULTS: In total, 445 patients with MS (64.9% female; mean [SD] age at baseline 45.0 [11.4] years; 11.2% with PMS) were enrolled. Compared with patients with RRMS, those with PMS had accelerated cervical cord atrophy (mean difference in annual percentage volume change [MD-APC] -1.41; p = 0.004) and higher PRL load (incidence rate ratio [IRR] 1.93; p = 0.005). Increased spinal cord atrophy (MD-APC -1.39; p = 0.0008) and PRL burden (IRR 1.95; p = 0.0008) were measured in patients with PIRA compared with patients without CDA; such differences were also confirmed when restricting the analysis to patients with RRMS. Baseline volumetric measurements of the cervical cord, whole brain, and cerebral cortex significantly predicted time to PIRA (all p ≤ 0.002). DISCUSSION: Our results show that PIRA is associated with both increased spinal cord atrophy and PRL burden, and this association is evident also in patients with RRMS. These findings further point to the need to develop targeted treatment strategies for PIRA to prevent irreversible neuroaxonal loss and optimize long-term outcomes of patients with MS.

B cell depletion attenuates CD27 signaling of T helper cells in multiple sclerosis.

Multiple sclerosis is a chronic inflammatory disease of the central nervous system. Whereas T cells are likely the main drivers of disease development, the striking efficacy of B cell-depleting therapies (BCDTs) underscore B cells' involvement in disease progression. How B cells contribute to multiple sclerosis (MS) pathogenesis-and consequently the precise mechanism of action of BCDTs-remains elusive. Here, we analyze the impact of BCDTs on the immune landscape in patients with MS using high-dimensional single-cell immunophenotyping. Algorithm-guided analysis reveals a decrease in circulating T follicular helper-like (Tfh-like) cells alongside increases in CD27 expression in memory T helper cells and Tfh-like cells. Elevated CD27 indicates disrupted CD27/CD70 signaling, as sustained CD27 activation in T cells leads to its cleavage. Immunohistological analysis shows CD70-expressing B cells at MS lesion sites. These results suggest that the efficacy of BCDTs may partly hinge upon the disruption of Th cell and B cell interactions.

Cell-binding IgM in CSF is distinctive of multiple sclerosis and targets the iron transporter SCARA5.

Intrathecal IgM production in multiple sclerosis is associated with a worse disease course. To investigate pathogenic relevance of autoreactive IgM in multiple sclerosis, CSF from two independent cohorts, including multiple sclerosis patients and controls, were screened for antibody binding to induced pluripotent stem cell-derived neurons and astrocytes, and a panel of CNS-related cell lines. IgM binding to a primitive neuro-ectodermal tumour cell line discriminated 10% of multiple sclerosis donors from controls. Transcriptomes of single IgM producing CSF B cells from patients with cell-binding IgM were sequenced and used to produce recombinant monoclonal antibodies for characterization and antigen identification. We produced five cell-binding recombinant IgM antibodies, of which one, cloned from an HLA-DR + plasma-like B cell, mediated antigen-dependent complement activation. Immunoprecipitation and mass spectrometry, and biochemical and transcriptome analysis of the target cells identified the iron transport scavenger protein SCARA5 as the antigen target of this antibody. Intrathecal injection of a SCARA5 antibody led to an increased T cell infiltration in an experimental autoimmune encephalomyelitis (EAE) model. CSF IgM might contribute to CNS inflammation in multiple sclerosis by binding to cell surface antigens like SCARA5 and activating complement, or by facilitating immune cell migration into the brain.

Harmonizing Definitions for Progression Independent of Relapse Activity in Multiple Sclerosis: A Systematic Review.

Importance: Emerging evidence suggests that progression independent of relapse activity (PIRA) is a substantial contributor to long-term disability accumulation in relapsing-remitting multiple sclerosis (RRMS). To date, there is no uniform agreed-upon definition of PIRA, limiting the comparability of published studies. Objective: To summarize the current evidence about PIRA based on a systematic review, to discuss the various terminologies used in the context of PIRA, and to propose a harmonized definition for PIRA for use in clinical practice and future trials. Evidence Review: A literature search was conducted using the search terms multiple sclerosis, PIRA, progression independent of relapse activity, silent progression, and progression unrelated to relapses in PubMed, Embase, Cochrane, and Web of Science, published between January 1990 and December 2022. Findings: Of 119 identified single records, 48 eligible studies were analyzed. PIRA was reported to occur in roughly 5% of all patients with RRMS per annum, causing at least 50% of all disability accrual events in typical RRMS. The proportion of PIRA vs relapse-associated worsening increased with age, longer disease duration, and, despite lower absolute event numbers, potent suppression of relapses by highly effective disease-modifying therapy. However, different studies used various definitions of PIRA, rendering the comparability of studies difficult. Conclusion and Relevance: PIRA is the most frequent manifestation of disability accumulation across the full spectrum of traditional MS phenotypes, including clinically isolated syndrome and early RRMS. The harmonized definition suggested here may improve the comparability of results in current and future cohorts and data sets.

Optical coherence tomography versus other biomarkers: Associations with physical and cognitive disability in multiple sclerosis.

BACKGROUND: Optical coherence tomography (OCT) is a biomarker of neuroaxonal loss in multiple sclerosis (MS). OBJECTIVE: The objective was to assess the relative role of OCT, next to magnetic resonance imaging (MRI) and serum markers of disability in MS. METHODS: A total of 100 patients and 52 controls underwent OCT to determine peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layers (GCIPL). Serum neurofilament light chain (sNfL), total lesion volume (TLV), and brain parenchymal fraction (BPF) were also assessed. The associations of OCT with disability were examined in linear regression models with correction for age, vision, and education. RESULTS: In patients, pRNFL was associated with the Symbol Digit Modalities Test (SDMT; p = 0.030). In the multivariate analysis including sNfL and MRI measures, pRNFL (ß = 0.19, p = 0.044) and TLV (ß = -0.24, p = 0.023) were the only markers associated with the SDMT. pRNFL (p < 0.001) and GCIPL (p < 0.001) showed associations with the Expanded Disability Status Scale (EDSS). In the multivariate analysis, GCIPL showed the strongest association with the EDSS (ß = -0.32, p < 0.001) followed by sNfL (ß = 0.18, p = 0.024). CONCLUSION: The associations of OCT measures with cognitive and physical disability were independent of serum and brain MRI markers of neuroaxonal loss. OCT can be an important tool for stratification in MS, while longitudinal studies using combinations of biomarkers are warranted.

A structured evaluation of cryopreservation in generating single-cell transcriptomes from cerebrospinal fluid.

Single-cell transcriptomics allows characterization of cerebrospinal fluid (CSF) cells at an unprecedented level. Here, we report a robust cryopreservation protocol adapted for the characterization of fragile CSF cells by single-cell RNA sequencing (RNA-seq) in moderate- to large-scale studies. Fresh CSF was collected from twenty-one participants at two independent sites. Each CSF sample was split into two fractions: one was processed fresh, while the second was cryopreserved for months and profiled after thawing. B and T cell receptor sequencing was also performed. Our comparison of fresh and cryopreserved data from the same individuals demonstrates highly efficient recovery of all known CSF cell types. We find no significant difference in cell type proportions and cellular transcriptomes between fresh and cryopreserved cells. Results were comparable at both sites and with different single-cell sequencing chemistries. Cryopreservation did not affect recovery of T and B cell clonotype diversity. Our CSF cell cryopreservation protocol provides an important alternative to fresh processing of fragile CSF cells.

Comparative analysis of dimethyl fumarate and teriflunomide in relapsing-remitting multiple sclerosis.

BACKGROUND AND PURPOSE: In relapsing-remitting multiple sclerosis (RRMS), analyses from observational studies comparing dimethyl fumarate (DMF) and teriflunomide showed conflicting results. We aimed to compare the effectiveness of DMF and teriflunomide in a real-world setting, where both drugs are licensed as first-line therapies for RRMS. METHODS: We included all patients who initiated DMF or teriflunomide between 2013 and 2022, listed in the Swiss National Treatment Registry. Coarsened exact matching was applied using age, gender, disease duration, baseline Expanded Disability Status Scale (EDSS) score, time since last relapse, and relapse rate in the previous year as matching variables. Time to relapse and time to 12-month confirmed EDSS worsening were compared using Cox proportional hazard models. RESULTS: In total, 2028 patients were included in this study, of whom 1498 were matched (DMF: n = 1090, 69.6% female, mean age 45.1 years, median EDSS score 2.0; teriflunomide: n = 408, 68.9% female, mean age 45.1 years, median EDSS score 2.0). Time to relapse and time to EDSS worsening was longer in the DMF than the teriflunomide group (hazard ratio 0.734, p = 0.026 and hazard ratio 0.576, p = 0.003, respectively). CONCLUSION: Analysis of real-world data showed that DMF treatment was associated with more favorable outcomes than teriflunomide treatment.

Immunoglobulin A Antibodies Against Myelin Oligodendrocyte Glycoprotein in a Subgroup of Patients With Central Nervous System Demyelination.

Importance: Differential diagnosis of patients with seronegative demyelinating central nervous system (CNS) disease is challenging. In this regard, evidence suggests that immunoglobulin (Ig) A plays a role in the pathogenesis of different autoimmune diseases. Yet little is known about the presence and clinical relevance of IgA antibodies against myelin oligodendrocyte glycoprotein (MOG) in CNS demyelination. Objective: To investigate the frequency of MOG-IgA and associated clinical features in patients with demyelinating CNS disease and healthy controls. Design, Setting, and Participants: This longitudinal study comprised 1 discovery and 1 confirmation cohort derived from 5 centers. Participants included patients with suspected or confirmed demyelinating diseases and healthy controls. MOG-IgA, MOG-IgG, and MOG-IgM were measured in serum samples and cerebrospinal fluid (CSF) of patients, who were assessed from September 2012 to April 2022. Main Outcomes and Measures: Frequency and clinical features of patients who were seropositive for MOG-IgA and double-seronegative for aquaporin 4 (AQP4) IgG and MOG-IgG. Results: After the exclusion of 5 participants with coexisting AQP4-IgG and MOG-IgA, MOG-IgG, and/or MOG-IgM, 1339 patients and 110 healthy controls were included; the median follow-up time was 39 months (range, 0-227 months). Of included patients with isolated MOG-IgA, 11 of 18 were female (61%), and the median age was 31.5 years (range, 3-76 years). Among patients double-seronegative for AQP4-IgG and MOG-IgG (1126/1339; 84%), isolated MOG-IgA was identified in 3 of 50 patients (6%) with neuromyelitis optica spectrum disorder, 5 of 228 patients (2%) with other CNS demyelinating diseases, and 10 of 848 patients (1%) with multiple sclerosis but in none of the healthy controls (0/110). The most common disease manifestation in patients seropositive for isolated MOG-IgA was myelitis (11/17 [65%]), followed by more frequent brainstem syndrome (7/16 [44%] vs 14/75 [19%], respectively; P = .048), and infrequent manifestation of optic neuritis (4/15 [27%] vs 46/73 [63%], respectively; P = .02) vs patients with MOG-IgG. Among patients fulfilling 2017 McDonald criteria for multiple sclerosis, MOG-IgA was associated with less frequent CSF-specific oligoclonal bands (4/9 [44%] vs 325/351 [93%], respectively; P < .001) vs patients with multiple sclerosis who were MOG-IgG/IgA seronegative. Further, most patients with isolated MOG-IgA presented clinical attacks after recent infection or vaccination (7/11 [64%]). Conclusion and Relevance: In this study, MOG-specific IgA was identified in a subgroup of patients who were double-seronegative for AQP4-/MOG-IgG, suggesting that MOG-IgA may be a novel diagnostic biomarker for patients with CNS demyelination.

Cerebrospinal Fluid HIV-1 Escape in Patients With Neurocognitive Symptoms: Pooled Data From a Neuro-HIV Platform and the NAMACO Study.

BACKGROUND: Despite modern antiretroviral therapy, human immunodeficiency virus-1 (HIV-1) ribonucleic acid (RNA) escape into the cerebrospinal fluid (CSF) may occur. We examined the prevalence of and factors associated with CSF HIV-1 escape among people living with HIV (PLWH) in Switzerland. SETTING: The Neurocognitive Assessment in the Metabolic and Aging Cohort study is an ongoing, prospective, longitudinal, multicenter study within the Swiss HIV Cohort Study. The neuro-HIV platform is a multidisciplinary, single-day outpatient consultation at Lausanne University Hospital. METHODS: We pooled data from the Neurocognitive Assessment in the Metabolic and Aging Cohort study and the neuro-HIV platform participants who underwent lumbar puncture between 2011 and 2019. Both patient groups had neurocognitive symptoms. Cerebrospinal fluid HIV-1 escape was defined as the presence of quantifiable CSF HIV-1 RNA when plasma HIV-1 RNA was suppressed or CSF HIV-1 RNA greater than plasma HIV-1 RNA when the latter was detectable. RESULTS: Of 1166 PLWH assessed, 288 underwent lumbar puncture. Cerebrospinal fluid HIV-1 escape was observed in 25 PLWH (8.7%) of whom 19 (76%) had suppressed plasma HIV-1 RNA. Characteristics of PLWH were comparable whether they had CSF HIV-1 escape or not, including comorbidities, time since HIV diagnosis (15 vs 16 years, P = 0.9), median CD4 nadir (158.5/mm 3 vs 171/mm 3 , P = 0.6), antiretroviral CSF penetration-effectiveness score (7 vs 7 points, P = 0.8), and neurocognitive diagnosis based on Frascati criteria and radiological findings. CONCLUSIONS: In this large pooled sample of PLWH with neurocognitive symptoms, CSF HIV-1 escape occurred in 8.7% of PLWH. People living with HIV with CSF HIV-1 escape presented no distinctive clinical or paraclinical characteristics. We conclude that lumbar puncture is unavoidable in confirming CSF HIV-1 escape.

Serum Glial Fibrillary Acidic Protein Compared With Neurofilament Light Chain as a Biomarker for Disease Progression in Multiple Sclerosis.

Importance: There is a lack of validated biomarkers for disability progression independent of relapse activity (PIRA) in multiple sclerosis (MS). Objective: To determine how serum glial fibrillary acidic protein (sGFAP) and serum neurofilament light chain (sNfL) correlate with features of disease progression vs acute focal inflammation in MS and how they can prognosticate disease progression. Design, Setting, and Participants: Data were acquired in the longitudinal Swiss MS cohort (SMSC; a consortium of tertiary referral hospitals) from January 1, 2012, to October 20, 2022. The SMSC is a prospective, multicenter study performed in 8 centers in Switzerland. For this nested study, participants had to meet the following inclusion criteria: cohort 1, patients with MS and either stable or worsening disability and similar baseline Expanded Disability Status Scale scores with no relapses during the entire follow-up; and cohort 2, all SMSC study patients who had initiated and continued B-cell-depleting treatment (ie, ocrelizumab or rituximab). Exposures: Patients received standard immunotherapies or were untreated. Main Outcomes and Measures: In cohort 1, sGFAP and sNfL levels were measured longitudinally using Simoa assays. Healthy control samples served as the reference. In cohort 2, sGFAP and sNfL levels were determined cross-sectionally. Results: This study included a total of 355 patients (103 [29.0%] in cohort 1: median [IQR] age, 42.1 [33.2-47.6] years; 73 female patients [70.9%]; and 252 [71.0%] in cohort 2: median [IQR] age, 44.3 [33.3-54.7] years; 156 female patients [61.9%]) and 259 healthy controls with a median [IQR] age of 44.3 [36.3-52.3] years and 177 female individuals (68.3%). sGFAP levels in controls increased as a function of age (1.5% per year; P < .001), were inversely correlated with BMI (-1.1% per BMI unit; P = .01), and were 14.9% higher in women than in men (P = .004). In cohort 1, patients with worsening progressive MS showed 50.9% higher sGFAP levels compared with those with stable MS after additional sNfL adjustment, whereas the 25% increase of sNfL disappeared after additional sGFAP adjustment. Higher sGFAP at baseline was associated with accelerated gray matter brain volume loss (per doubling: 0.24% per year; P < .001) but not white matter loss. sGFAP levels remained unchanged during disease exacerbations vs remission phases. In cohort 2, median (IQR) sGFAP z scores were higher in patients developing future confirmed disability worsening compared with those with stable disability (1.94 [0.36-2.23] vs 0.71 [-0.13 to 1.73]; P = .002); this was not significant for sNfL. However, the combined elevation of z scores of both biomarkers resulted in a 4- to 5-fold increased risk of confirmed disability worsening (hazard ratio [HR], 4.09; 95% CI, 2.04-8.18; P < .001) and PIRA (HR, 4.71; 95% CI, 2.05-9.77; P < .001). Conclusions and Relevance: Results of this cohort study suggest that sGFAP is a prognostic biomarker for future PIRA and revealed its complementary potential next to sNfL. sGFAP may serve as a useful biomarker for disease progression in MS in individual patient management and drug development.

Natalizumab in cerebrospinal fluid and breastmilk of patients with multiple sclerosis.

Background: Natalizumab is a highly effective monoclonal antibody for the treatment of multiple sclerosis (MS), which can diffuse in different anatomical compartments, including cerebrospinal fluid (CSF) and milk. Objectives: Starting from incidental detection of natalizumab in the CSF of MS patients, the objective of this study was to develope a flow-cytometry-based assay and apply it to quantify natalizumab in body fluids, including milk collected from nursing patients over 180 days and in patients with neutralizing antibodies against natalizumab. Methods: CSF, milk and sera samples from patients with multiple sclerosis were tested by flow-cytometry for binding to a VLA-4 expressing cell line or to a control cell line. A standard curve was prepared by incubating the same cells with natalizumab at 50 µg/ml and serially diluted to 0.005 ng/ml. Binding specificity was confirmed using an anti-natalizumab neutralizing antibody. Results: Our assay was sensitive enough to detect natalizumab in CSF, with a lower detection limit of 1.5 ng/ml. Neutralizing antibodies against natalizumab inhibited binding to the cell line. In breastmilk, the peak concentration was observed during the first 2 weeks after infusion and the average concentration over the observation time was 173.3 ng/ml, with a trend toward increased average milk concentration over subsequent administrations. Conclusion: Routine use of such an assay would enable a better understanding of the safety of therapeutic antibody administration during pregnancy and lactation.