Pathophysiology of myelin oligodendrocyte glycoprotein antibody disease

Clinical utility of complete blood count indices in pediatric MOG antibody-associated disease

OBJECTIVE

The purpose of this study was to analyze the utility of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in pediatric myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

METHODS

Retrospective review of medical record was performed to analyze association among complete blood count (CBC) indices and clinical characteristics of pediatric MOGAD patients.

RESULTS

61 patients were included in the analysis. In 24 subjects with matched CBC samples, NLR, PLR, and monocyte-to-lymphocyte ratio (MLR) were higher during disease relapse than in remission. In the receiver operating characteristics (ROC) curve analysis, the optimal cutoff values were 2.55 and 179.4 for NLR and PLR, respectively. The area under curve (AUC) was 0.809 and 0.658 for NLR and PLR, respectively. At disease onset, NLR and PLR were higher in patients in the relapsing group. In the ROC curve analysis, the optimal cutoff values were 3.35 and 183.8 with the AUC of 0.739 and 0.700 for NLR and PLR, respectively. In logistic regression analysis, NLR and PLR elevation were statistically significant after adjusting for age, sex, and phenotype. The pooled analysis of all clinical attacks in the relapsing group revealed that NLR and PLR are lower in the isolated optic neuritis (ON) compared to the other phenotypes.

CONCLUSION

This study shows that in pediatric MOGAD patients, NLR and PLR are useful for prompt recognition of disease relapse and prediction of relapsing course at disease onset. NLR and PLR are also associated with clinical phenotypes in pediatric MOGAD.

Multiple sclerosis: an immune attack on astrocyte-mediated ion and water homeostasis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the CNS. The chain of events that results in demyelinating lesions is not understood, although most theories assume a primary immune attack on myelin. However, the glial cell adhesion molecule GlialCAM, which forms part of a protein complex in astrocytic endfeet that is crucial for brain ion and water homeostasis, was recently identified as a target for autoimmunity in patients with MS. This complex also includes the astrocytic transmembrane protein MLC1, the water channel aquaporin 4 (AQP4) and the potassium channel KIR4.1. Autoimmunity against AQP4 underlies another demyelinating disorder, neuromyelitis optica, and autoimmunity against KIR4.1 has been implicated in a subtype of MS. Genetic defects in any of these proteins cause leukodystrophies with disruption of brain ion and water homeostasis, which is regulated by astrocytes and secondarily affects myelin. In this Perspective, we argue that an immune attack on the ion and water homeostasis machinery in astrocytic endfeet, rather than directly on myelin, is the primary event in MS and that myelin damage is a consequence of astrocyte dysfunction. This hypothesis is supported by pathological studies on tissue from people with MS and has important implications for disease models and therapy targets.

Applications of Machine Learning-Driven Molecular Models for Advancing Ophthalmic Precision Medicine

Ophthalmic diseases such as glaucoma, age-related macular degeneration (ARMD), and optic neuritis involve complex molecular and cellular disruptions that challenge current diagnostic and therapeutic approaches. Advanced artificial intelligence (AI) and machine learning (ML) models offer a novel lens to analyze these diseases by integrating diverse datasets, identifying patterns, and enabling precision medicine strategies. Over the past decade, applications of AI in ophthalmology have expanded from imaging-based diagnostics to molecular-level modeling, bridging critical gaps in understanding disease mechanisms. This paper systematically reviews the application of AI-driven methods, including reinforcement learning (RL), graph neural networks (GNNs), Bayesian inference, and generative adversarial networks (GANs), in the context of these ophthalmic conditions. RL models simulate transcription factor dynamics in hypoxic or inflammatory environments, offering insights into disrupted molecular pathways. GNNs map intricate molecular networks within affected tissues, identifying key inflammatory or degenerative drivers. Bayesian inference provides probabilistic models for predicting disease progression and response to therapies, while GANs generate synthetic datasets to explore therapeutic interventions. By contextualizing these AI tools within the broader framework of ophthalmic disease management, this review highlights their potential to transform diagnostic precision and therapeutic outcomes. Ultimately, this work underscores the need for continued interdisciplinary collaboration to harness AI's potential in advancing the field of ophthalmology and improving patient care.

Do specific myelin autoantibodies and increased cerebral dopamine neurotrophic factor in the context of inflammation predict the diagnosis of attention deficit hyperactivity disorder in medication-free children?

BACKGROUND

The aim of this study was to investigate the serum levels of anti-myelin basic protein (anti-MBP), anti-myelin oligodentrocyte glycoprotein (anti-MOG), myelin-associated glycoprotein (MAG), high-sensitivity C-reactive protein (hs-CRP), cerebral dopamine neurotrophic factor (CDNF), cerebellin-1, and reelin and their relationships with clinical severity and irritability behaviours in children with attention deficit (AD) hyperactivity disorder (ADHD) and typically developing (TD) healthy controls.

METHODS

In this study, 141 children with ADHD between the ages of 8 and 14 years who were medication-free and 135 TD healthy controls were included. The serum levels of anti-MBP, anti-MOG, MAG, CDNF, hs-CRP, cerebellin, and reelin were measured using enzyme-linked immunosorbent assay kits. The Turgay Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV)-based Screening and Evaluation Scale for Attention Deficit and Disruptive Behavior Disorders-Parent Form (TDSM-IV-O) and the affective reactivity index (ARI) scale were used to assess clinical severity and irritability behaviours in the children.

RESULTS

The MAG, CDNF, hs-CRP, reelin, and cerebellin levels were significantly higher in the ADHD group than in the control group, but no significant differences in anti-MBP and anti-MOG levels were found between the groups. Compared with the controls, the patients with ADHD showed significantly higher scores on the ARI self- and parent-report scales. The reelin, hs-CRP, and MAG levels were significantly associated with the TDSM-IV-O AD scores, AD and oppositional defiant (OD) disorder scores and hyperactivity, and OD and conduct disorder scores, respectively. Hs-CRP was significantly associated with anti-MBP and cerebellin levels. In an analysis of covariance, the results were unchanged even after controlling for potential confounders such as age, body mass index, and sex.

CONCLUSION

This study demonstrates that MAG, CDNF, hs-CRP, reelin, and cerebellin levels may play a potential role in the pathogenesis of ADHD.

Pain and Headache in Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

PURPOSE OF REVIEW

The purpose of this review is to evaluate the current knowledge and recent findings on different pain and headache presentations associated with Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD) disease.

RECENT FINDINGS

MOGAD is an inflammatory autoimmune disease affecting mostly the central nervous system, presenting with optic neuritis, transverse myelitis and other forms of inflammatory demyelination. Pain and headache in MOGAD have been recognized more recently and acute and chronic forms of pain can occur in both the adult and pediatric population. An important recent observation is that MOGAD can affect the peripheral nervous system, which can contribute to pain symptoms. Acute and chronic forms of pain have been described in MOGAD, including ocular pain, different types of headaches and neuropathies, involving the central and peripheral nervous system. Awareness of these types of pain in both the pediatric and adult population is crucial, to ensure timely diagnosis and treatment.

Small RNA sequencing of differentiated astrocytoma exposed to NMOSD patient sera reveals perturbations in neurodegenerative signaling

The signaling pathways behind severe astrocytic lysis with Aquaporin4 auto-antibody (AQP4-IgG) seropositivity, and reactive astrocytosis with myelin oligodendrocyte glycoprotein auto-antibody (MOG-IgG) seropositivity, remain largely unexplored in Neuromyelitis optica spectrum disorder (NMOSD), while almost no molecular details being known about double-seronegative (DN) patients. Recent discovery of glial fibrillary acidic protein (GFAP) in DN NMOSD patients' cerebrospinal fluid, akin to AQP4-IgG + ve cases, suggests astrocytopathy. Here, we aim to study small non coding RNA (sncRNA) signature alterations in astrocytes exposed to AQP4-IgG + ve and MOG-IgG + ve patient sera, and their potential resemblance with DN-NMOSD. Next Generation Sequencing (NGS) revealed differential expression of several microRNAs with notable alterations in hsa-miR-6824-3p, hsa-miR-324-5p and hsa-miR-4466 respectively upon sera treatment. Results with DN-NMOSD patient sera are majorly similar to that of AQP4+ve sera. Strikingly, in all three treatments, hsa-miR-200b-3p was significantly upregulated. Functional enrichment analysis revealed that Hippo and FoxO signaling pathways were primarily impacted in AQP4-IgG + ve and double negative sera treated cells whereas, MOG-IgG + ve sera treatment perturbed the PI3K-Akt and MAPK signaling pathways. Furthermore, NGS also revealed differential expression of several piRNAs in cells upon treatment with AQP4-IgG + ve and MOG-IgG + ve sera and VEGF signaling was identified as the common target of differentially expressed piRNAs of both the groups. This study, for the first time, revealed that the molecular pathophysiology of double-seronegative NMOSD might involve astrocytopathy akin to AQP4+ve NMOSD, thus pointing towards the possible existence of unidentified astrocytic autoimmune targets and identified the major alterations in intracellular sncRNAs and the associated overall cellular signaling pathways that potentially contribute to the fate of astrocytes during the progression of the disease.

Neuroglia in autoimmune encephalitis

Neuroglial cells play a crucial role in central nervous system (CNS) health and disease. Antibody-associated autoimmune encephalitis (AE) represents a group of inflammatory brain diseases with antibodies (Abs) against neuronal cell surface (e.g., anti-N-methyl-d-aspartate receptor (NMDAR), anti-leucine-rich glioma-inactivated 1 (LGI1), γ-aminobutyric acid (GABA) type A or B receptor (GABAA/BR)) or intracellular neuronal proteins. AE with Abs against glial antigens, e.g., myelin oligodendrocyte glycoprotein (MOG), glial fibrillary acidic protein (GFAP) are also described. Besides the known pathomechanisms with direct pathogenic effects of primary neuronal Abs and activation of innate (dendritic cells) and adaptive (B and T cells) immune systems, research findings suggest the involvement of glial cells including astrocytes, microglia, oligodendrocytes in the pathogenesis of Ab-associated AE, but only a limited number of studies is available. Neuropathologic findings showed reactive astrogliosis and microgliosis with microglial activation/proliferation, e.g., in anti-NMDAR and anti-LGI1 encephalitis. Direct effects of the GABAAR and NMDAR Abs on astrocytic receptors are discussed. Because of the primary involvement of B and T cells in the pathogenesis of Ab-associated AE it can be assumed that astrocytic and microglial activation is largely a response to the primary changes, but additional direct effects of Abs on astrocytic receptors are possible. Further research in this field is required to explore the exact role of glial cells in Ab-associated AE.

MOGAD and NMOSD: insights on patients' radiological and laboratory findings from a single UAE center

Introduction

Although neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are rare diseases, they pose a significant burden on both society and the healthcare system. This study aims to discuss the demographics and patient characteristics of these diseases in a single center in the United Arab Emirates (UAE).

Methods

This is a retrospective, descriptive study that included patients with either NMOSD or MOGAD treated at Rashid Hospital, UAE during the period between January 2019 and January 2024. Patients were selected and categorized according to NMOSD criteria, aquaporin-4 antibodies, and MOG antibodies. Patient demographics, clinical characteristics, and medical history were retrieved from their medical records and descriptively analyzed in the light of patients' serological data.

Results

We identified 34 patients with non-multiple sclerosis atypical CNS inflammatory/demyelinating syndromes. Twenty-seven patients (79.4%) fulfilled the criteria for NMOSD, while seven (20.6%) tested positive for MOG antibodies, fulfilling the criteria for MOGAD. In the NMOSD cohort, 19% (n = 5) were AQP4-antibody negative. Seventy-four percent of the NMOSD cohort and 43% of the MOGAD cohort were female. For MOGAD patients, disease onset was at a younger age (median onset age of 25 years) compared to the overall study population (mean onset age of 28.94 years). Long segment transverse myelitis was only detected in NMOSD patients (33.3%), and brainstem syndrome with area postrema syndrome was more common in the MOGAD cohort (29% vs. 4%). The rate of positive response to intravenous methylprednisolone as initial therapy was comparable across both cohorts (74% in case of NMOSD and 71% in case of MOGAD).

Conclusion

This study provides valuable insights into the status of NMOSD and MOGAD in the UAE, highlighting the need for larger, prospective studies to further characterize these diseases in the local population, as well as the need for improved understanding of the epidemiology and management of these rare but debilitating conditions.

Pediatric acquired demyelinating syndromes: updates in diagnosis, testing, and management

PURPOSE OF REVIEW

To highlight the clinical presentation, diagnostic approach, and management of acquired inflammatory demyelinating syndromes in children.

RECENT FINDINGS

The identification of myelin oligodendrocyte glycoprotein antibody-associated disease in 2017 and evolving evidence regarding best practices for management has had a significant impact on pediatric neuroimmunology, as has the shift in treatment of pediatric-onset multiple sclerosis, with the use of high-efficacy disease-modifying therapies early in the disease course.

SUMMARY

With expanding awareness and growing interest in pediatric onset neuroinflammatory conditions, the number of children diagnosed with acquired demyelinating syndromes is rising. It is critical to refine our understanding of the underlying pathophysiological mechanisms in these disorders to provide the most effective care. Much of our practice continues to be modeled on adult care, and further large-scale pediatric studies are necessary to explore the natural history and assess the safety and efficacy of immunotherapies in childhood-onset demyelinating diseases.

Blood-Brain Barrier Disruption in Neuroimmunological Disease

The blood-brain barrier (BBB) acts as a structural and functional barrier for brain homeostasis. This review highlights the pathological contribution of BBB dysfunction to neuroimmunological diseases, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), autoimmune encephalitis (AE), and paraneoplastic neurological syndrome (PNS). The transmigration of massive lymphocytes across the BBB caused by the activation of cell adhesion molecules is involved in the early phase of MS, and dysfunction of the cortical BBB is associated with the atrophy of gray matter in the late phase of MS. At the onset of NMOSD, increased permeability of the BBB causes the entry of circulating AQP4 autoantibodies into the central nervous system (CNS). Recent reports have shown the importance of glucose-regulated protein (GRP) autoantibodies as BBB-reactive autoantibodies in NMOSD, which induce antibody-mediated BBB dysfunction. BBB breakdown has also been observed in MOGAD, NPSLE, and AE with anti-NMDAR antibodies. Our recent report demonstrated the presence of GRP78 autoantibodies in patients with MOGAD and the molecular mechanism responsible for GRP78 autoantibody-mediated BBB impairment. Disruption of the BBB may explain the symptoms in the brain and cerebellum in the development of PNS, as it induces the entry of pathogenic autoantibodies or lymphocytes into the CNS through autoimmunity against tumors in the periphery. GRP78 autoantibodies were detected in paraneoplastic cerebellar degeneration and Lambert-Eaton myasthenic syndrome, and they were associated with cerebellar ataxia with anti-P/Q type voltage-gated calcium channel antibodies. This review reports that therapies affecting the BBB that are currently available for disease-modifying therapies for neuroimmunological diseases have the potential to prevent BBB damage.

The influence of MOGAD on diagnosis of multiple sclerosis using MRI

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an immune-mediated demyelinating disease that is challenging to differentiate from multiple sclerosis (MS), as the clinical phenotypes overlap, and people with MOGAD can fulfil the current MRI-based diagnostic criteria for MS. In addition, the MOG antibody assays that are an essential component of MOGAD diagnosis are not standardized. Accurate diagnosis of MOGAD is crucial because the treatments and long-term prognosis differ from those for MS. This Expert Recommendation summarizes the outcomes from a Magnetic Resonance Imaging in MS workshop held in Oxford, UK in May 2022, in which MS and MOGAD experts reflected on the pathology and clinical features of these disorders, the contributions of MRI to their diagnosis and the clinical use of the MOG antibody assay. We also critically reviewed the literature to assess the validity of distinctive imaging features in the current MS and MOGAD criteria. We conclude that dedicated orbital and spinal cord imaging (with axial slices) can inform MOGAD diagnosis and also illuminate differential diagnoses. We provide practical guidance to neurologists and neuroradiologists on how to navigate the current MOGAD and MS criteria. We suggest a strategy that includes useful imaging discriminators on standard clinical MRI and discuss imaging features detected by non-conventional MRI sequences that demonstrate promise in differentiating these two disorders.

Physical Exercise Counteracts Aging-Associated White Matter Demyelination Causing Cognitive Decline

In the central nervous system, oligodendrocytes wrap around neuronal axons to form myelin, an insulating layer or sheath that allows for the efficient conductance of action potentials. In addition to structural insulation, myelin provides encased axons with nutrient, metabolic and defensive support. Demyelination, or myelin loss, can therefore cause axonal dysfunction, leading to neurological impairment and disease. In Alzheimer's disease (AD), progressive white matter demyelination is acknowledged as one of the earliest pathologies preceding symptom onset. Unfortunately, current pharmacotherapy for slowing demyelination or promoting remyelination in AD is nonexistent. Exercise is recognized for its wide-ranging benefits to human health, including improved mental health and the prevention of lifestyle-related diseases. Mounting evidence suggests the contribution of physical activity in delaying the progression of dementia in elderly populations. Recent mechanistic studies have shown that exercise facilitates myelination in the brain through the vitalization of intrinsic pro-myelination cues, such as increased neurotrophic factors and electrical activity. In this review, we summarize and discuss the potential of physical exercise on counteracting aging-associated white matter demyelination, which causes cognitive decline in AD. We highlight the need of further basic and clinical research investigations on this topic to establish novel approaches for healthy and improved brain aging.

Infections Combined With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease: A Case Report and Systematic Review of the Literature

Myelinating oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an immune-mediated inflammatory demyelinating disease of the central nervous system. Its specific etiology and pathogenesis remain unclear. In recent years, there have been increasing reports of MOGAD occurring after infections. Even cases of concurrent infection and MOGAD have been documented. We report a clinical case of a 14-year-old male patient admitted to the hospital with a fever and loss of consciousness. He underwent thorough medical examinations. The results of second-generation sequencing of the metagenome of the cerebrospinal fluid revealed that he was infected with Haemophilus parainfluenzae, and serum testing showed positive MOG antibodies. He was discharged after improving with intravenous immunoglobulin and other treatments.

MOG-antibody-associated transverse myelitis with the H-sign and unusual MRI enhancement: a case report and literature review

Transverse myelitis is the second most common symptoms in myelin oligodendrocyte antibody-associated diseases (MOGAD), causing obvious clinical manifestation. T2-hyperintense lesions mainly restricted to the gray matter in the spinal cord on axial magnetic resonance imaging, produce the H-sign, which is thought to be the typical finding of MOGAD. Contrast enhancement can be observed in some cases of myelin oligodendrocyte antibody-associated transverse myelitis (MOG-TM). However, reports on the enhancement pattern associated with the H-sign are rarely seen. In this report, we describe a case of pediatric MOG-TM in which the H-sign was observed without enhancement, while the surrounding white matter exhibited enhancement. This pattern contradicts the previously observed gray matter involvement. Then we reviewed the literatures of myelin oligodendrocyte antibody-positive myelitis to focus on the neuroimaging features and discuss the implications of our finding.

Myelin Oligodendrocyte Glycoprotein Antibody Disease (MOGAD)-Monophasic Optic Neuritis and Epstein-Barr Virus (EBV): A Case Report of Rare Comorbid Diagnoses in an Adolescent From a Remote Greek Island

A unique case of a female adolescent diagnosed with myelin oligodendrocyte glycoprotein (MOG) monophasic optic neuritis with Epstein-Barr virus (EBV) reactivation antibody profile on a remote Greek island is presented, highlighting the challenges of diagnosing rare conditions in rural settings and the importance of connecting centers of expertise with regional hospitals. The 16-year-old patient presented with progressive vision loss, headache, and retrobulbar pain in the right eye. Initial ophthalmological examinations showed decreased visual acuity and color vision deterioration. Magnetic resonance imaging (MRI) revealed optic perineuritis and edema. Cerebrospinal fluid (CSF) analysis excluded oligoclonal bands, and blood analysis was positive for both anti-MOG antibodies and EBV reactivation. Expert opinion and blood immunophenotyping confirmed the neuroimmunological condition. This case not only underscores the value of telemedicine in overcoming diagnostic challenges in rural settings but also contributes to the scientific discussion on neuroimmunological aspects and the potential role of EBV as an underlying factor in acquired demyelinating syndromes (ADS), beyond multiple sclerosis (MS).

MOG Antibody Disease: Nuances in Presentation, Diagnosis, and Management

PURPOSE OF REVIEW

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a distinct neuroinflammatory condition characterized by attacks of optic neuritis, transverse myelitis, and other demyelinating events. Though it can mimic multiple sclerosis and neuromyelitis optica spectrum disorder, distinct clinical and radiologic features which can discriminate these conditions are now recognized. This review highlights recent advances in our understanding of clinical manifestations, diagnosis, and treatment of MOGAD.

RECENT FINDINGS

Studies have identified subtleties of common clinical attacks and identified more rare phenotypes, including cerebral cortical encephalitis, which have broadened our understanding of the clinicoradiologic spectrum of MOGAD and culminated in the recent publication of proposed diagnostic criteria with a familiar construction to those diagnosing other neuroinflammatory conditions. These criteria, in combination with advances in antibody testing, should simultaneously lead to wider recognition and reduced incidence of misdiagnosis. In addition, recent observational studies have raised new questions about when to treat MOGAD chronically, and with which agent. MOGAD pathophysiology informs some of the relatively unique clinical and radiologic features which have come to define this condition, and similarly has implications for diagnosis and management. Further prospective studies and the first clinical trials of therapeutic options will answer several remaining questions about the peculiarities of this condition.

NMOSD and MOGAD

OBJECTIVE

This article reviews the clinical features, MRI characteristics, diagnosis, and treatment of aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). The main differences between these disorders and multiple sclerosis (MS), the most common demyelinating disease of the central nervous system (CNS), are also highlighted.

LATEST DEVELOPMENTS

The past 20 years have seen important advances in understanding rare demyelinating CNS disorders associated with AQP4 IgG and myelin oligodendrocyte glycoprotein (MOG) IgG. The rapidly expanding repertoire of immunosuppressive agents approved for the treatment of AQP4-NMOSD and emerging as potentially beneficial in MOGAD mandates prompt recognition of these diseases. Most of the recent literature has focused on the identification of clinical and MRI features that help distinguish these diseases from each other and MS, simultaneously highlighting major diagnostic pitfalls that may lead to misdiagnosis. An awareness of the limitations of currently available assays for AQP4 IgG and MOG IgG detection is fundamental for identifying rare false antibody positivity and avoiding inappropriate treatments. For this purpose, diagnostic criteria have been created to help the clinician interpret antibody testing results and recognize the clinical and MRI phenotypes associated with AQP4-NMOSD and MOGAD.

ESSENTIAL POINTS

An awareness of the specific clinical and MRI features associated with AQP4-NMOSD and MOGAD and the limitations of currently available antibody testing assays is crucial for a correct diagnosis and differentiation from MS. The growing availability of effective treatment options will lead to personalized therapies and improved outcomes.

Clinical, Demographic, and Radiological Characteristics of Patients Demonstrating Antibodies Against Myelin Oligodendrocyte Glycoprotein

Background

Optic neuritis, myelitis, and neuromyelitis optica spectrum disorder (NMOSD) have been associated with antibodies against myelin oligodendrocyte glycoprotein-immunoglobulin G (anti-MOG-IgG). Furthermore, patients with radiological and demographic features atypical for multiple sclerosis (MS) with optic neuritis and myelitis also demonstrate antibodies against aquaporin-4 and anti-MOG-IgG. However, data on the diagnosis, treatment, follow-up, and prognosis in patients with anti-MOG-IgG are limited.

Aims

To evaluate the clinical, radiological, and demographic characteristics of patients with anti-MOG-IgG.

Study Design

Multicenter, retrospective, observational study.

Methods

Patients with blood samples demonstrating anti-MOG-IgG that had been evaluated at the Neuroimmunology laboratory at Ondokuz Mayıs University’s Faculty of Medicine were included in the study.

Results

Of the 104 patients with anti-MOG-IgG, 56.7% were women and 43.3% were men. Approximately 2.4% of the patients were diagnosed with MS, 15.8% with acute disseminated encephalomyelitis (ADEM), 39.4% with NMOSD, 31.3% with isolated optic neuritis, and 11.1% with isolated myelitis. Approximately 53.1% of patients with spinal involvement at clinical onset demonstrated a clinical course of NMOSD. Thereafter, 8.8% of these patients demonstrated a clinical course similar to MS and ADEM, and 28.1% demonstrated a clinical course of isolated myelitis. The response to acute attack treatment was lower and the disability was higher in patients aged > 40 years than patients aged < 40 years at clinical onset. Oligoclonal band was detected in 15.5% of the patients.

Conclusion

For patients with NMOSD and without anti-NMO antibodies, the diagnosis is supported by the presence of anti-MOG-IgG. Furthermore, advanced age at clinical onset, Expanded Disability Status Scale (EDSS) score at clinical onset, spinal cord involvement, and number of attacks may be negative prognostic factors in patients with anti-MOG-IgG.

Neuromyelitis Optica Spectrum Disorders and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

For over two centuries, clinicians have been aware of various conditions affecting white matter which had come to be grouped under the umbrella term multiple sclerosis. Within the last 20 years, specific scientific advances have occurred leading to more accurate diagnosis and differentiation of several of these conditions including, neuromyelitis optica spectrum disorders and myelin oligodendrocyte glycoprotein antibody disease. This new understanding has been coupled with advances in disease-modifying therapies which must be accurately applied for maximum safety and efficacy.

Uncovering the Diagnostic Challenge of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease: A Case Study of Acute Bilateral Vision Loss

We discuss a perplexing case of a 51-year-old female with a history of asthma and morbid obesity, presenting with acute bilateral vision loss of unknown etiology. The patient's clinical course was marked by a constellation of symptoms, including blurry vision, eyeball pain, photophobia, headache, nausea, and dizziness, prompting a multidisciplinary approach for diagnostic evaluation. Despite a comprehensive workup and a temporal artery biopsy ruling out large vessel arteritis, the etiology of vision loss remained elusive until myelin oligodendrocyte glycoprotein (MOG) antibody testing returned positive, implicating myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). High-dose corticosteroid therapy was initiated. However, the patient had worsening visual symptoms and was started on plasmapheresis and subsequent administration of Rituximab to prevent relapses, along with a long-term steroid taper regimen. This case underscores the diagnostic challenge of optic neuritis, particularly in MOGAD. It emphasizes the importance of a thorough evaluation and multidisciplinary collaboration.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Clinical and radiological spectrum of acquired inflammatory demyelinating diseases of the central nervous system in a tertiary care center

Objectives

Demyelinating diseases of central nervous system (CNS) are a broad spectrum of conditions with autoimmune process against myelin. In a resource limited country like India, it is imperative to perform proper clinical evaluation, neuroimaging to differentiate among various categories of CNS demyelinating diseases to decide regarding further workup and treatment. The objective of our study was to determine clinical presentation, imaging findings, serology results, diagnosis, and treatment outcome of primary demyelinating disorders of CNS.

Materials and Methods

In this prospective study, a total of 44 patients were enrolled over a period of 1 year. After proper evaluation, patients were categorized into different groups applying newer diagnostic criteria. Patients were treated with steroids, appropriate immunomodulatory therapy, and outcomes were analyzed.

Results

The majority of cases were of neuromyelitis optica spectrum disorder (NMOSD) (45.5%) with an overall female-to-male ratio of 3.4:1 and mean age of presentation was 30.5 ± 11.15. Myelitis (52.3%) followed by optic neuritis (45.5%) was the most common initial presentation. The most common site of involvement on magnetic resonance imaging was the spinal cord (particularly the cervicodorsal cord). The majority showed good response to therapy (77.27%) and two patients did not survive.

Conclusion

Higher disability observed among seropositive NMOSD patients warrants aggressive treatment during the first attack itself. It is important to suspect myelin oligodendrocyte glycoprotein antibody disease in patients with preceding viral infection. A good outcome in the majority is likely due to the availability of serological assays and aggressive immunomodulatory therapy.

Manifestations of Myelinating Oligodendrocyte Glycoprotein Antibody-Associated Disease: A Rare Case of Suppurative Meningoencephalitis

Myelinating oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory demyelinating disease of the central nervous system (CNS) mediated by MOG antibodies (MOG-IgG). It is associated with autoimmunity and encompasses various syndromes. However, manifestations presenting with symptoms of suppurative meningoencephalitis are rare. In this case, we admitted an 80-year-old male patient who presented with fever, headache, mental and behavioral abnormalities, and disturbance of consciousness. The cerebrospinal fluid (CSF) examination revealed elevated levels of leukocytes and protein, while magnetic resonance imaging (MRI) of the brain showed an abnormal signal in the parietal lobe surrounding the posterior horn of the right lateral ventricle. The patient tested positive for serum MOG-IgG, confirming the diagnosis of MOG-IgG-related meningoencephalitis. The treatment included intravenous immunoglobulin, glucocorticoids, third-generation cephalosporins, and immunosuppressants. Following the treatment, the patient experienced complete recovery.

Monoclonal antibodies in neuro-ophthalmology

Neuro-ophthalmologic diseases include a broad range of disorders affecting the afferent and efferent visual pathways. Recently, monoclonal antibody (mAb) therapies have emerged as a promising targeted approach in the management of several of these complex conditions. Here, we describe the mechanism-specific applications and advancements in neuro-ophthalmologic mAb therapies. The application of mAbs in neuro-ophthalmologic diseases highlights our increasing understanding of disease-specific mechanisms in autoimmune conditions such as neuromyelitis optica, thyroid eye disease, and myasthenia gravis. Due to the specificity of mAb therapies, applications in neuro-ophthalmologic diseases have yielded exceptional clinical outcomes, including both reduced rate of relapse and progression to disability, visual function preservation, and quality of life improvement. These advancements have not only expanded the range of treatable neuro-ophthalmologic diseases but also reduced adverse events and increased the response rate to treatment. Further research into neuro-ophthalmologic disease mechanisms will provide accurate and specific targeting of important disease mediators through applications of future mAbs. As our understanding of these diseases and the relevant therapeutic targets evolve, we will continue to build on our understanding of how mAbs interfere with disease pathogenesis, and how these changes improve clinical outcomes and quality of life for patients.

Delimiting MOGAD as a disease entity using translational imaging

The first formal consensus diagnostic criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) were recently proposed. Yet, the distinction of MOGAD-defining characteristics from characteristics of its important differential diagnoses such as multiple sclerosis (MS) and aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorder (NMOSD) is still obstructed. In preclinical research, MOG antibody-based animal models were used for decades to derive knowledge about MS. In clinical research, people with MOGAD have been combined into cohorts with other diagnoses. Thus, it remains unclear to which extent the generated knowledge is specifically applicable to MOGAD. Translational research can contribute to identifying MOGAD characteristic features by establishing imaging methods and outcome parameters on proven pathophysiological grounds. This article reviews suitable animal models for translational MOGAD research and the current state and prospect of translational imaging in MOGAD.

A comprehensive review of the advances in neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare relapsing neuroinflammatory autoimmune astrocytopathy, with a predilection for the optic nerves and spinal cord. Most cases are characterised by aquaporin-4-antibody positivity and have a relapsing disease course, which is associated with accrual of disability. Although the prognosis in NMOSD has improved markedly over the past few years owing to advances in diagnosis and therapeutics, it remains a severe disease. In this article, we review the evolution of our understanding of NMOSD, its pathogenesis, clinical features, disease course, treatment options and associated symptoms. We also address the gaps in knowledge and areas for future research focus.

Susceptibility-based imaging aids accurate distinction of pediatric-onset MS from myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) and pediatric-onset multiple sclerosis (POMS) share clinical and magnetic resonance imaging (MRI) features but differ in prognosis and management. Early POMS diagnosis is essential to avoid disability accumulation. Central vein sign (CVS), paramagnetic rim lesions (PRLs), and central core lesions (CCLs) are susceptibility-based imaging (SbI)-related signs understudied in pediatric populations that may help discerning POMS from MOGAD.

METHODS

T2-FLAIR and SbI (three-dimensional echoplanar imaging (3D-EPI)/susceptibility-weighted imaging (SWI) or similar) were acquired on 1.5T/3T scanners. Two readers assessed CVS-positive rate (%CVS+), and their average score was used to build a receiver operator curve (ROC) assessing the ability to discriminate disease type. PRLs and CCLs were identified using a consensual approach.

RESULTS

The %CVS+ distinguished 26 POMS cases (mean age 13.7 years, 63% females, median EDSS 1.5) from 14 MOGAD cases (10.8 years, 35% females, EDSS 1.0) with ROC = 1, p < 0.0001, (cutoff 41%). PRLs were only detectable in POMS participants (mean 2.1±2.3, range 1-10), discriminating the two conditions with a sensitivity of 69% and a specificity of 100%. CCLs were more sensitive (81%) but less specific (71.43%).

CONCLUSION

The %CVS+ and PRLs are highly specific markers of POMS. After proper validation on larger multicenter cohorts, consideration should be given to including such imaging markers for diagnosing POMS at disease onset.

NF-κB and STAT3 activation in CD4 T cells in pediatric MOG antibody-associated disease

In this study, we examined CD4 T cell activation using various stimuli in pediatric MOGAD patients (n = 4, untreated remission samples) and healthy controls (n = 5), to understand how both antigen-specific and bystander mechanisms contribute to CD4 T cell activation in MOGAD. TNFα, IL6, and MOG peptide pool were found to activate NF-κB or STAT3 pathways by measuring the expression of regulators (A20, IκBα) and phosphorylated subunits (phospho-p65 and phospho-STAT3) using immunolabeling. Prednisolone reversed activation of both NF-κB and STAT3 and increased the expression of A20 and IκBα. TNFR blocking partially reversed NF-κB activation in certain CD4 T cell subsets, but did not effect STAT3 activation. We observed that activation of NF-κB and STAT3 in response to various stimuli behaves mostly same in MOGAD (remission) and HC. IL6 stimulation resulted in higher STAT3 phosphorylation in MOGAD patients at 75 min, specifically in central and effector memory CD4 T cells (with unadjusted p-values). These findings suggest the potential therapeutic targeting of NF-κB and STAT3 pathways in MOGAD. Further investigation is needed to validate the significance of extended STAT3 phosphorylation and its correlation with IL6 receptor blocker treatment response.

Pathogenesis, Clinical Features, and Treatment of Patients with Myelin Oligodendrocyte Glycoprotein (MOG) Autoantibody-Associated Disorders Focusing on Optic Neuritis with Consideration of Autoantibody-Binding Sites: A Review

Although there is a substantial amount of data on the clinical characteristics, diagnostic criteria, and pathogenesis of myelin oligodendrocyte glycoprotein (MOG) autoantibody-associated disease (MOGAD), there is still uncertainty regarding the MOG protein function and the pathogenicity of anti-MOG autoantibodies in this disease. It is important to note that the disease characteristics, immunopathology, and treatment response of MOGAD patients differ from those of anti-aquaporin 4 antibody-positive neuromyelitis optica spectrum disorders (NMOSDs) and multiple sclerosis (MS). The clinical phenotypes of MOGAD are varied and can include acute disseminated encephalomyelitis, transverse myelitis, cerebral cortical encephalitis, brainstem or cerebellar symptoms, and optic neuritis. The frequency of optic neuritis suggests that the optic nerve is the most vulnerable lesion in MOGAD. During the acute stage, the optic nerve shows significant swelling with severe visual symptoms, and an MRI of the optic nerve and brain lesion tends to show an edematous appearance. These features can be alleviated with early extensive immune therapy, which may suggest that the initial attack of anti-MOG autoantibodies could target the structures on the blood-brain barrier or vessel membrane before reaching MOG protein on myelin or oligodendrocytes. To understand the pathogenesis of MOGAD, proper animal models are crucial. However, anti-MOG autoantibodies isolated from patients with MOGAD do not recognize mouse MOG efficiently. Several studies have identified two MOG epitopes that exhibit strong affinity with human anti-MOG autoantibodies, particularly those isolated from patients with the optic neuritis phenotype. Nonetheless, the relations between epitopes on MOG protein remain unclear and need to be identified in the future.

Pathology of myelin oligodendrocyte glycoprotein antibody-associated disease: a comparison with multiple sclerosis and aquaporin 4 antibody-positive neuromyelitis optica spectrum disorders

Myelin oligodendrocyte glycoprotein (MOG) is expressed on the outermost layer of the myelin sheath in the central nervous system. Recently, the clinical concept of MOG antibody-associated disease (MOGAD) was established based on the results of human MOG-transfected cell-based assays which can detect conformation-sensitive antibodies against MOG. In this review, we summarized the pathological findings of MOGAD and discussed the issues that remain unresolved. MOGAD pathology is principally inflammatory demyelination without astrocyte destruction, characterized by perivenous demyelination previously reported in acute disseminated encephalomyelitis and by its fusion pattern localized in both the white and gray matter, but not by radially expanding confluent demyelination typically seen in multiple sclerosis (MS). Some of demyelinating lesions in MOGAD show severe loss of MOG staining compared with those of other myelin proteins, suggesting a MOG-targeted pathology in the disease. Perivascular cuffings mainly consist of macrophages and T cells with CD4-dominancy, which is also different from CD8+ T-cell-dominant inflammation in MS. Compared to aquaporin 4 (AQP4) antibody-positive neuromyelitis optica spectrum disorders (NMOSD), perivenous complement deposition is less common, but can be seen on myelinated fibers and on myelin degradation products within macrophages, resembling MS Pattern II pathology. Thus, the pathogenetic contribution of complements in MOGAD is still debatable. Together, these pathological features in MOGAD are clearly different from those of MS and AQP4 antibody-positive NMOSD, suggesting that MOGAD is an independent autoimmune demyelinating disease entity. Further research is needed to clarify the exact pathomechanisms of demyelination and how the pathophysiology relates to the clinical phenotype and symptoms leading to disability in MOGAD patients.