Neurology Neuroimmunology & Neuroinflammation

Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system with a complex etiology. Recent genomic studies highlight the contribution of expression quantitative trait loci (eQTLs) in modulating gene expression and disease susceptibility. Given the emerging role of circular RNAs (circRNAs) in MS, we hypothesized that genetic variants may regulate circRNA expression through circRNA-specific eQTLs (circ-eQTLs). We performed a cis-circ-eQTL analysis integrating circRNA expression and whole-genome genotyping data from 30 MS patients and 18 healthy controls using a linear regression model adjusted for disease status and sex. Candidate circ-eQTLs were prioritized based on MS-associated regions and known splicing QTLs (sQTLs) from GTEx and validated in an independent cohort (67 MS, 64 controls). Association analysis in a larger cohort (2831 MS, 3191 controls) evaluated two candidate variants for MS risk. We identified 42,077 significant cis-circ-eQTLs and validated three. Two SNPs, rs7214410 and rs11079784, modulated hsa_circ_0106983 expression, and rs7214410 also acted as an sQTL affecting EFCAB13 splicing. rs7214410 showed stronger association with MS than rs11079784. Our findings reveal extensive genetic regulation of circRNA expression and highlight rs7214410 as a dual-function variant refining the MS susceptibility locus on chromosome 17.

BackgroundDisorders affecting the spinal cord (myelopathies) can cause severe disability. Despite diagnostic advances, approximately 12-18% of myelopathy cases continue to elude an etiological diagnosis, hampering effective treatment. MethodsThis retrospective, multicenter, tertiary care cohort study conducted from 2014 to 2025 evaluated archived biofluids from patients with IM, known autoimmune myelitis, or other neurological diseases (ONDs). Proteome-wide phage display was used to discover novel autoantibodies. Targeted immunoassays were used to screen for a candidate autoantibody. Downstream metabolites were measured in the cerebrospinal fluid (CSF). ResultsAutoantibodies targeting the transcobalamin receptor (CD320) responsible for cellular transport of vitamin B12 were identified in 18 out of 32 IM patients (56%) in a discovery cohort. Bioactive B12 concentration was decreased in the CSF of anti-CD320 positive patients compared to OND controls (P = 0.0273), indicative of autoimmune B12 central deficiency (ABCD). Compared to anti-CD320 negative IM cases, anti-CD320 positive IM cases demonstrated a higher frequency of subacute time course (56% vs 7%, P = 0.008), normal CSF profile (83% vs 50%, P = 0.044), and dorsolateral spinal cord abnormalities on magnetic resonance imaging (MRI) (61% vs 7%, P = 0.003). In two independent validation cohorts comprising 94 and 25 patients with IM, anti-CD320 was detected in 43 (46%) and 12 (48%) patients, respectively. Comorbid anti-CD320 was detected in a smaller proportion of patients with other known autoimmune etiologies of myelopathy. Five anti-CD320 positive IM patients received B12 supplementation with or without concurrent immunosuppression, and four out of five clinically improved. ConclusionsABCD is associated with a substantial proportion of IM. Screening for anti-CD320 followed by metabolic confirmation of a CNS-restricted B12 deficiency may be considered in the diagnostic evaluation of myelopathy.

Purpose: Aicardi-Goutieres syndrome (AGS) is a type I interferonopathy presently associated with nine genes. PTPN1 is a negative regulator of the interferon pathway previously associated with chronic inflammation and recently type 1 IFN autoinflammation. Methods: Genomic data from undiagnosed individuals with suspected AGS were interrogated for PTPN1 variants, and predicted loss-of-function (pLOF) and damaging missense variants in PTPN1 were sought in two additional academic databases as well as the All of Us database. Results: We identified 13 cases with ultra-rare heterozygous pLOF or highly damaging missense variants in PTPN1. Nine cases were identified in a cohort of 53 individuals (~ 17%) with clinical, imaging and persistent biochemical features of AGS. Median age of onset is 1.75 years (IQR 0.67), significantly later (p< 0.0001) than other AGS genotypes. Four additional cases were identified in academic datasets with variable clinical features suggestive of autoinflammation. Additionally, 49 individuals with ultra-rare, damaging PTPN1 variants were identified in the All of Us database, none had features suggestive of AGS, but autoimmunity was highly prevalent (~21.6%). Conclusion: Our data implicate PTPN1 as a cause of later-onset presentations of AGS within a broader spectrum of autoinflammatory phenotypes. Segregation and biobank data demonstrate reduced penetrance, with carriers being enriched for autoimmune disorders.

BackgroundMultiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) that affects both the brain and spinal cord, although the brain has historically received greater attention. In the inducible, oligodendrocyte-specific knockout model of Myrf, which results in white matter damage to both the brain and spinal cord, our laboratory previously demonstrated that the brain undergoes partial remyelination following white matter damage, whereas the spinal cord fails to do so. We also observed that brain microglia display a much stronger activation than spinal cord microglia in this model. Microglia regulate remyelination by clearing myelin debris, processing resulting lipids, and modulating an inflammation response. ResultsHere, to test our hypothesis, we characterized microglial phenotypes during demyelination in both tissues. The brain exhibited greater early microglial recruitment and higher baseline expression of activation and phagocytic markers, suggesting a primed state for responding to damage. In contrast, spinal cord microglia showed delayed phagocytic marker expression, sustained inflammation, and a predominately amoeboid morphology during demyelination. ConclusionsTogether, these findings indicate that brain microglia mount a timely and coordinated response to demyelination that supports remyelination, whereas spinal cord microglia adopt a dysfunctional phenotype that may contribute to impaired myelin repair.

Despite important advances in understanding the etiopathology of multiple sclerosis, factors determining disease progression remain partially understood and often difficult to predict. Specific diagnostic and prognostic biomarkers are needed to optimize the risk-benefit ratio of treatment for each patient. The aim of our study was to identify a cerebrospinal fluid proteomic signature associated with diagnosis and short- to mid-term prognosis across the multiple sclerosis continuum. Our multicentric cohort study analyzed CSF samples from 120 patients using a proteomics data-independent acquisition strategy. Differentially expressed proteins were identified across diagnostic groups: 62 patients with multiple sclerosis, 15 patients with clinically isolated syndrome, and 43 healthy controls. We also compared the CSF of patients with no evidence of disease activity with those with disease activity at 2 and 5 years of follow-up. A diagnostic and prognostic classification model was built using iterative cross-validated logistic regression models on shared differentially expressed proteins across these two comparisons. A total of 1,257 proteins were quantified, and 162 differentially expressed proteins were identified across comparisons. We identified a set of ten proteins associated with the diagnosis and prognosis of multiple sclerosis, including previously identified potential biomarkers (CH3L2, IGHG1, IGKC, LAMP2, ADA2), proteins known to be involved in the pathophysiology of multiple sclerosis (A0A8J8YUT9, AT2A2, CO3A1) and two yet unreported proteins (DSC2 and MMRN2). Multivariate models based on these proteins achieved good accuracy for the diagnosis of MS compared with CIS (area under the receiver operating characteristics curve [AUROC] up to 80% using 3 proteins) and prognosis (NEDA vs. EDA; AUROC up to 96% at 2 and 5 years; using 5 proteins). These results, which will require further investigation to validate the new biomarkers, open new perspectives on multiple sclerosis pathophysiology and therapeutic targets.

ObjectiveTo replicate and extend recent findings suggesting that higher serum alpha-linolenic acid (ALA) levels are associated with reduced disease activity and progression in multiple sclerosis (MS). MethodsWe reanalysed clinical trial data from 85 people with MS, who had serum ALA, magnetic resonance imaging (MRI), and clinical (EDSS, PASAT) assessments collected for two years, with additional follow-up at 12-years. Linear and mixed models were used to assess the relationship between ALA and clinical and MRI outcomes. Mediation analyses tested whether ALA mediated associations between brain volume or T2 lesion load, and disability. ResultsALA measures were consistent over time ({kappa}= 0.83). Higher ALA predicted lower EDSS ({beta} = -0.41, 95% CI [-0.73, -0.08]) and larger brain volume ({beta} = 0.22, 95% CI [0.09, 0.36]). ALA was a non-significant mediator of brain volume or lesion effects on EDSS and did not predict long-term clinical or cognitive change. DiscussionWe replicate prior associations between higher serum-ALA levels and reduced disability in MS and extend these by showing a beneficial association of serum-ALA with brain volume. However, ALA did not predict long-term progression, limiting its prognostic value.

BackgroundThe prodromal phase of multiple sclerosis (MS) is increasingly recognized, but most studies have focused on isolated symptoms or static comorbidity counts, leaving the evolving structure of pre-onset disease burden underexplored. ObjectiveTo characterize dynamic disease trajectories preceding MS onset through longitudinal network modeling. MethodsHealth data from 10,273 MS patients and 47,167 matched controls in Sweden were analyzed. Disease co-occurrence networks were constructed for three pre-onset windows (0-5, 5-10, 10-15 years), with comparisons of centrality, clustering, and path length. Rewiring scores captured structural shifts, while Markov clustering and trajectory mapping identified comorbidity communities. ResultsMS networks were denser, more clustered, and showed shorter path lengths than controls, reflecting higher systemic interconnectivity. Psychiatric and metabolic diagnoses, especially depression, anxiety, diabetes, and abdominal pain, were hubs that gained prominence over time. Distinct clusters, including neuropsychiatric-toxicological and immune-endocrine constellations, were observed only in MS. Rewiring analysis revealed significant topological shifts in key diagnoses, such as inflammatory CNS disorders and substance use, as onset approached. ConclusionsMS is preceded by dynamic reorganization of the comorbidity landscape, marked by increasing connectivity and rewired hubs. This framework highlights systemic disruption before diagnosis and provides a novel, network-based tool for studying prodromes in complex disorders.

BackgroundNeurological Long COVID (n-LC) includes persistent cognitive and autonomic symptoms after SARS-CoV-2 infection. Prior studies of post-COVID conditions have described diverse humoral autoreactivity, but findings are heterogeneous, and it remains unclear whether n-LC is associated with a consistent CNS-directed humoral signature. MethodsWe performed a cross-cohort case-control analysis to detect autoantibodies in cerebrospinal fluid (CSF) and serum from n-LC participants. In the Yale COVID Mind Study cohort, CSF from n-LC participants and from pre-pandemic and post-COVID asymptomatic controls was assessed by mouse brain immunofluorescence and proteome-wide phage immunoprecipitation sequencing (PhIP-Seq), with candidate reactivities evaluated by orthogonal assays and supervised modeling. In the Epidemiology, Immunology, and Clinical Characteristics of Emerging Infectious Diseases with Pandemic Potential (IDCRP EPICC) cohort, post-COVID sera collected prior to iPhone- or iPad-based cognitive screening were profiled by PhIP-Seq and compared between participants with and without cognitive impairment. ResultsCSF immunoreactivity on mouse brain tissue was observed in both n-LC and controls, with similar overall frequencies, although n-LC participants more often showed nuclear-predominant staining patterns. PhIP-Seq identified sparse, largely patient-specific peptide reactivities to nuclear and neuronal proteins in CSF and serum. Supervised models provided limited discrimination between cases and controls. Candidate autoantigens had limited disease specificity on orthogonal testing. EPICC serum autoantibody profiling similarly failed to distinguish individuals with and without cognitive impairment. ConclusionsAcross cohorts and compartments, n-LC did not exhibit a shared autoantibody signature. These findings support the absence of a dominant, common CNS autoantibody-mediated mechanism in n-LC. FundingGrants HU00012020067, HU00012120103, HU00011920111, R01NS125693, R01MH125737, R01AI157488 from Defense health program and NIH.

Background / ObjectivesWe investigated whether the interthalamic adhesion (IA), a midline structure connecting the thalami, is altered in MS and associated with thalamic damages and cognition. MethodsWe prospectively included 32 clinically isolated syndrome/early MS, 31 RRMS, 31 PPMS patients, and 103 matched controls. All underwent anatomical 3T MRI and completed a comprehensive cognitive battery. IA presence, subtype, and volume were assessed by two blinded readers. Thalamic nuclei and other brain structures were segmented automatically. We compared IA subtypes/volumes across groups, analyzed their predictors and explored cognitive associations with multivariate regressions. ResultsIA prevalence did not differ between MS and controls (81.9% vs 74.7%). MS patients showed a shift toward a short IA subtype and reduced IA volume (mean [SD], 146.8 [117.9] vs 230.2 [138.2] mm3; p<0.0001), worsening across phenotypes. Reduced IA volume was independently associated with medial and posterior thalamic nuclei volumes, but not with white matter lesion load or global atrophy. Among cognitive domains, smaller IA volume was independently associated only with executive dysfunction (OR = 0.89 [0.77-0.99], p = 0.021). ConclusionIA volume reduction in MS reflects vulnerability of adjacent thalamic nuclei and is associated with executive dysfunction, supporting IA as a marker of thalamic neurodegeneration. Trial RegistrationMICROSEP: NCT03692975; AUBACOG: NCT03768648; PROCOG: NCT03455582.

Patients with myasthenia gravis (MG) may produce autoantibodies neutralizing type I interferons (AAN-I-IFN), which have been shown to underlie severe viral diseases, including critical COVID-19 pneumonia, in patients without MG. We studied an international cohort of 85 unvaccinated SARS-CoV-2-infected MG patients with no antiviral treatment. Hypoxemic pneumonia occurred in 48 of these patients, including 22 (45.8%) with AAN-I-IFN, which neutralized both IFN-2 and IFN-{omega} in 14 (29.2%) patients. Six (16.2%) of the remaining 37 patients had AAN-I-IFN, which neutralized both IFN-2 and IFN-{omega} in three patients. The risk of hypoxemic pneumonia was greater in MG patients with AAN-I-IFN neutralizing 10 ng/mL of both IFN-2 and IFN-{omega} (odds ratio and 95% confidence interval (OR [95% CI]): 12.7 [2.1-78.9], p=0. 0010) or IFN-2 at any dose (4.7 [1.5-15.0], p=0.0054) than in those without such autoantibodies. The risk of AAN-I-IFN production was much higher in MG patients than in the general population (28.9 [10.8-77.7], p=4.9x10-27). Fourteen patients had thymoma, which increased the risk of AAN-I-IFN (64% versus 27%, (OR [95% CI]: 5.6 [1.6-19.4], p=0.0050) and hypoxemic pneumonia (9.2 [1.9-44.2]; p=0.0019). Thymoma is, thus, associated with a higher risk of producing AAN-I-IFN, and these autoantibodies are associated with a higher risk of developing life-threatening COVID-19 pneumonia in patients with MG.

An overlap syndrome of myositis and/or myocarditis associated with myasthenia gravis (MG) has emerged as a life-threatening immune-related adverse event (irAE) in cancer patients treated with immune checkpoint inhibitors (ICIs). This syndrome closely resembles a rare form of idiopathic inflammatory myopathy (IIM) seen in a subset of MG patients. In this systematic review, we searched PubMed for reports of concurrent MG and IIM as well as ICI-related overlap syndromes. By integrating clinical, serological, and pathological observations, we delineated a previously unrecognized clinicopathological subtype of myositis that overlaps with MG. This entity is defined by a strong association with striational antibodies (StrAbs) and frequent co- occurrence with thymoma as a paraneoplastic process, and we classify it as StrAb-associated myositis. The idiopathic and ICI-induced forms share similar, though not identical, clinical, serological, and histopathological characteristics. We found that AChR antibody positivity, independent of established clinical risk factors such as respiratory or cardiac involvement, predicted more severe ICI-myotoxicity. Together with supporting evidence, our findings suggest a pathogenic model in which thymoma-driven cytotoxic T-cell responses trigger secondary AChR autoimmunity. These results highlight the potential utility of StrAbs and anti-AChR antibodies as practical biomarkers for diagnosis, risk stratification, and early intervention in patients at risk for severe neuromuscular irAEs.

Multiple sclerosis (MS) is an autoimmune and neurological disorder characterized by myelin disruption and neuronal degeneration. Currently approved therapies focus on symptom relief but do not promote central nervous system (CNS) repair. In contrast, astrocytes proliferate and repopulate MS-related lesions. Moreover, in active lesions, they hinder regenerative processes such as neural progenitor migration. Here, we propose astrocytes as a potential target for myelin repair in the human diseased brain. To achieve this aim, we investigated whether glial fibrillary acidic protein (GFAP)+ astrocytes can be transdifferentiated into oligodendrocyte lineage cells through forced overexpression of transcription factors both in vitro and ex vivo organotypic cultures of human adult cortex. Our results show that overexpression of OLIG2 and SOX10 in human induced pluripotent stem cell-derived astrocytes gives rise to oligodendrocyte progenitor cells 12 days post-induction, as shown by morphological changes and O4 marker expression. Importantly, transdifferentiation of GFAP-expressing endogenous astrocytes in human adult cortical tissue give rise to mature oligodendrocytes, as shown by expression of CC1, after only 12 days of overexpression of OLIG2 and SOX10. To our knowledge, this is the first study to assess direct astrocyte-to-oligodendrocyte reprogramming in a human platform preserving the native three-dimensional architecture of the brain. Further work will be required to determine whether the reprogrammed cells can myelinate axons and to evaluate the potential of this approach for structural and functional repair in the demyelinated human CNS.

Clinically silent MRI lesions occur frequently in people with relapsing-remitting multiple sclerosis (RRMS) despite disease modifying therapy (DMT). Guidelines only recommend DMT escalation after multiple silent lesions, and adherence is variable. We explored outcomes and the effect of treatment escalation following single and multiple on-treatment silent lesions. This cohort study and emulated target trial used MSBase registry data from 99 clinics in 26 countries between 2007 and 2025. Clinically stable participants receiving any DMT for RRMS with silent lesions versus without silent lesions were compared. Among participants with silent lesions while taking platform or moderate-efficacy DMTs, outcomes following treatment escalation within 6 months versus no treatment escalation (unless a post-MRI clinical event occurred) were compared. The primary outcome was an MS relapse, and the secondary outcome was 6-month confirmed disability worsening. A total of 10,232 participants met inclusion criteria (71.7% female, mean age 41 [SD 11]). The 2-year cumulative incidence of relapse was 27.8% (95% CI 25.7%-29.9%) in participants with silent lesions versus 14.3% (95% CI 13.5%-15.2%) without (adjusted hazard ratio [aHR] 1.76 [95% CI 1.57-1.97]). The 2-year cumulative incidence of disability worsening was 13.8% (95% CI 12.2%-15.5%) in participants with silent lesions versus 11.4% (95% CI 10.7%-12.2%) without (aHR 1.38 [95% CI 1.18-1.62]). Rates of relapse and disability worsening were higher following single and multiple silent lesions versus no silent lesions. The emulated trial included 2,264 participants with [&ge;]1 silent lesion on platform or moderate efficacy DMTs, 286 of whom escalated DMT within 6 months following silent lesions. The 4-year cumulative incidence of relapse was lower following treatment escalation (16.8% [95% CI 12.4%-23.4%]) versus continuation (38.9% [95% CI 35.8%-42.1%]), aHR 0.34 (95% CI 0.23-0.47), with similar aHRs following single and multiple silent lesions. The 4-year cumulative incidence of disability worsening was similar following treatment escalation (16.0% [95% CI 10.8%-22.2%]) versus continuation (17.7% [95% CI 15.3%-20.1%]), aHR 0.89 (95% CI 0.56-1.33). People with RRMS with single or multiple on-treatment silent MRI lesions have higher subsequent risks of relapse and disability worsening than people without silent lesions. DMT escalation mitigates the relapse risk, though disability worsening continues at a similar rate over 4 years. Contrary to guidelines, DMT escalation should be considered after single or multiple silent lesions.

IntroductionThe major histocompatibility complex class II (MHC-II) pathway is central to adaptive immunity and immune tolerance, and age-related erosion of these mechanisms is increasingly recognized as a driver of chronic neuroinflammation. The HLA-DRB1*15:01 allele--the strongest genetic risk factor for multiple sclerosis in Caucasians--has been implicated in shaping pathogenic CD4 T-cell responses and broader neuroimmune vulnerability, yet how this allele modulates age- and sex-dependent neuroimmune processes within the central nervous system (CNS) remains poorly defined. MethodsWe investigated the impact of HLA-DRB1*15:01 expression using a humanized mouse model (HLA mice) and wild-type (WT) controls. Male and female mice were analyzed at 6, 9, and 15 months of age, with endocrine stratification in females. Behavioral testing, flow cytometry, immunofluorescence, and multiplex cytokine analyses were used to assess cognitive performance, glial activation and oxidative stress, astrocyte-microglia IL-3/IL-3R signaling, endothelial activation, selective immune cell accumulation at CNS borders, tissue organization, and hippocampal cytokine profiles. ResultsHLA mice developed age- and sex-dependent cognitive impairment, most pronounced in aged females. HLA-DRB1*15:01 expression promoted progressive microglial activation, characterized by increased CD14 and CD68 expression, elevated mitochondrial oxidative stress, altered astrocyte phenotypes, and enhanced IL-3/IL-3R signaling. Hippocampal axonal and myelin organization was disrupted in aged HLA mice, and this disruption was spatially associated with increased microglial presence. At CNS interfaces, HLA mice exhibited selective immune remodeling, including increased accumulation of CD4 T cells and NK1.1CD3 natural killer T (NKT) cells, particularly in females, accompanied by endothelial activation, as evidenced by elevated ICAM-1 and E-selectin expression. Hippocampal cytokine profiling revealed selective, sex-biased alterations, including increased IL-12p70 and reduced IL-10 and IL-2, without broad induction of classical inflammatory cytokines. ConclusionTogether, these findings demonstrate that HLA-DRB1*15:01 drives a coordinated, age- and sex-dependent neuroinflammatory program linking behavioral dysfunction, glial activation and oxidative stress, selective immune cell recruitment, endothelial activation, tissue remodeling, and targeted cytokine imbalance. This integrated phenotype provides mechanistic insight into how this major MS risk allele confers vulnerability to chronic neuroinflammation during aging, with heightened impact in females.

Muscle-specific kinase (MuSK) is a pivotal player in forming and maintaining healthy neuromuscular junctions (NMJ). In MuSK myasthenia gravis (MG), autoantibodies targeting MuSK disrupt its function, impairing neuromuscular transmission and causing fatigable skeletal muscle weakness. MuSK autoantibodies predominantly belong to the IgG4 subclass, which bind in a monovalent fashion due to Fab-arm exchange, although autoantibodies of other subclasses also exist. Polyclonal autoreactive IgG from patients may therefore harbor a variety of monovalent and bivalent MuSK antibodies with potentially distinct effects on MuSK signaling. To further unravel the pathomechanisms underlying MuSK MG, we have investigated how MuSK antibody-binding affects MuSK functioning with a diverse panel of (patient-derived) monoclonal MuSK antibodies. Our findings reveal that the valency of antibody-binding influences binding kinetics to MuSK, inhibition of agrin-induced MuSK activation, Dok7 binding to MuSK and NMJ gene expression. Monovalent binding to the frizzled domain of MuSK did not inhibit agrin-induced MuSK activation, while monovalent binding to the Ig-like domain 1 does. Moreover, the kinetics of Dok7 degradation induced by bivalent MuSK antibodies appear to depend on binding-epitope of MuSK. Surprisingly, none of the clones tested (both bivalent and monovalent) increased MuSK internalization. Taken together, the cumulative pathogenic effect of polyclonal MuSK antibodies in individual MuSK MG patients thus likely depends on autoantibody titer, affinity and the unique composition of MuSK autoantibodies varying in epitope and valency. This research enriches our understanding of the intricate interactions between antibodies and MuSK in MuSK MG and offers potential insights into novel therapeutic strategies using MuSK antibodies.

IntroductionThe 2024 McDonald criteria incorporate the central vein sign (CVS) and paramagnetic rim lesions (PRL) as supportive imaging biomarkers for MS diagnosis. While susceptibility-weighted-imaging (SWI) and T2*-weighted echo-planar-imaging (EPI) are generally used to assess CVS/PRL, their relative performance remains unclear. This study compared high-resolution isotropic-T2*-EPI with non-isotropic SWI for CVS/PRL detection. Materials and MethodsIn this multi-centre study, 21 patients with MS underwent harmonized 3T-MRI including EPI and SWI. CVS and PRL were evaluated according to NAIMS criteria. Whole-brain and controlled lesion analyses on 120 pre-selected lesions were performed independently for each contrast, with EPI serving as reference standard. ResultsIn whole-brain analyses, SWI showed good sensitivity for CVS eligibility and positivity (AC1=0.68-0.78) but significant directional disagreement with EPI (p<0.0001). Discrepancies were primarily attributed to limited lesion-parenchyma contrast and venous visibility on SWI, which improved using low-flip-angle SWI. Controlled lesion analyses supported these observations. For PRL, SWI demonstrated high sensitivity (88%) and precision (97%) compared to EPI, though systematic bias persisted (p<0.001). Controlled lesion analyses showed more balanced, albeit moderate performance. ConclusionSWI diverged systematically from EPI for CVS and PRL detection. When available, EPI should be preferred, while optimised low-flip-angle SWI may serve as an alternative to conventional SWI.

BackgroundPeople with multiple sclerosis (pwMS) often experience impaired quality of life (QoL) despite receiving standard care. Digital therapeutics (DTx) may offer support, but prior trials yielded mixed results, possibly due to active controls and high baseline QoL. We therefore evaluated a DTx (levidex) as an adjunct to treatment as usual (TAU) in pwMS with impaired QoL. MethodsIn this pragmatic, online randomised controlled trial (LAMONT; NCT06090305), n = 470 pwMS with a score [&ge;]2 on the Hamburg Quality of Life Questionnaire in Multiple Sclerosis (HAQUAMS) were randomised to levidex + TAU or TAU alone. The primary endpoint was HAQUAMS total score at 6 months, analysed by intention-to-treat ANCOVA. ResultsCompared with TAU, levidex + TAU improved MS-specific QoL at 6 months (baseline-adjusted mean difference -0.10; 95% CI -0.18 to -0.03; p = 0.008; Cohens d = 0.26). Clinically relevant HAQUAMS improvement ([&ge;]0.22) occurred more often with levidex (39.5% vs 27.8%; number needed to treat = 9). Benefits also emerged for depressive symptoms and social/work functioning but not for anxiety. No serious adverse events occurred and user satisfaction was high. ConclusionsIn pwMS with impaired QoL, adding the scalable DTx levidex to TAU yields meaningful improvements in QoL and functioning.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis involves dynamic changes in glutamatergic signalling. Magnetic resonance spectroscopy can monitor these changes but lacks temporal resolution and cell-type specificity. We investigated whether urinary astrocyte-derived extracellular vesicles (ADEVs) could serve as a non-invasive proxy for brain receptor dynamics. We prospectively collected longitudinal urine and cerebrospinal fluid (CSF) samples from a 30- 35-year-old female patient during 34 days of treatment. We isolated ADEVs using a specific protocol and measured GluN1 protein levels. A 30-35-year-old healthy female provided control samples. Wavelet transform analysis of the patient's GluN1 time series revealed two distinct patterns. First, a low-frequency trend showed declining GluN1 levels over the treatment period, which mirrored the reduction in CSF GluN1 concentrations. Second, a high-frequency oscillation appeared to be coupled with methotrexate infusions, with GluN1 peaks occurring approximately 48 hours after each dose. This secondary increase may reflect drug-induced p53 activation, which promotes the exosomal release of internalised receptors. These findings suggest that urinary ADEVs provide a feasible and informative method to monitor real-time molecular fluxes in the brain.

PurposeTo characterize microstructural alterations across distinct white matter tissue classes in MS using Standard Model Imaging (SMI), and to place its performance in context relative to conventional diffusion tensor imaging (DTI). MethodsDTI and SMI were applied to treatment-naive individuals at early stages of MS, including patients with MS and healthy controls. Over 3,602 manually delineated regions of interest were classified into normal white matter (NWM), normal-appearing white matter (NAWM), T2-hyperintense lesions, and chronic black holes (cBHs) differences were assessed using linear mixed-effects models with false discovery rate correction. Discriminative performance was evaluated using receiver operating characteristic (ROC) analysis within a generalized linear mixed modeling framework for individual parameters and multivariate DTI, SMI, and combined DTI+SMI models. ResultsBoth DTI and SMI metrics demonstrated widespread and significant differences across tissue classes. Robust discriminative performance was observed for lesion-NWM and lesion-NAWM comparisons (AUC > 0.8), whereas discrimination between NAWM and NWM and between cBHs and T2-lesions was limited (AUC [&le;] 0.66). In terms of model performance, SMI achieved slightly higher AUC values than DTI across most contrasts, while the combined DTI+SMI model consistently provided the highest diagnostic performance. ROI-based analyses revealed additional SMI alterations, including changes in extra-axonal parallel diffusivity, not consistently reported in prior studies. ConclusionDTI and SMI metrics are sensitive to microstructural abnormalities across a broad spectrum of white matter tissue classes in MS, capturing both lesion-related damage and more subtle alterations extending into NAWM. While discriminative performance varies by tissue contrast, integrating DTI and SMI provides complementary information and modestly improves diagnostic performance, supporting a multi-model diffusion MRI approach for comprehensive characterization of MS-related white matter pathology

The cuprizone (CPZ) lesioned mouse is a widely used model of demyelination and remyelination, but most studies rely on histology at terminal timepoints, limiting understanding of disease dynamics. Here, we present a longitudinal multimodal magnetic resonance imaging and spectroscopy (MRI/MRS) study of CPZ-induced pathology, pooling control arms from three independent experiments (n = 40). Mice were imaged at baseline, then exposed to 0.2% cuprizone for 5 weeks and repeatedly imaged at days 24, 35, 49, 63 and 77 after the start of CPZ. Imaging included multiparametric mapping (MPM), diffusion tensor imaging (DTI), tensor-based morphometry (TBM), and single-voxel MRS in the corpus callosum. Histology (MBP, silver, GFAP, Iba1) was performed at selected timepoints for validation. An additional group of 18 CPZ-lesioned mice were imaged ex vivo using a different higher resolution MRI protocol and compared against 19 non-CPZ controls. MPM-derived MTsat{delta} and R1 reductions indicated robust demyelination in the corpus callosum and deep cerebellar nuclei by day 24, expanding to cortex and hippocampus by day 35. Partial recovery was observed by day 77 but changes persisted, consistent with histological evidence. TBM revealed dynamic volumetric alterations, including hippocampal and cerebellar expansion alongside cortical and subcortical shrinkage, persisting beyond CPZ cessation. DTI demonstrated early (days 24-35) decreases in FA and MD, followed by complex trajectories consistent with microstructural disruption and partial repair. MRS detected early increases in GABA, glutamine, taurine, and glutathione, with corresponding decreases in NAA, while inositol showed a biphasic decrease-increase profile, likely reflecting acute astrocytic dysfunction followed by gliosis - neuroinflammatory processes that were corroborated by immunohistochemistry. Together, these results demonstrate that multimodal MRI/MRS sensitively captures widespread, dynamic, and only partially reversible pathology in CPZ-treated mice. Longitudinal imaging provides a non-invasive, translational approach to characterising demyelination, gliosis, and remyelination, offering a powerful alternative to histology for preclinical studies and longitudinal therapeutic screening.