Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease: Current Insights into the Disease Pathophysiology, Diagnosis and Management

Antioxidant PRDX3 gene therapy protects brain cells and prevents neurodegeneration in an animal model of Parkinson's disease

Neurodegenerative diseases, including Parkinson's Disease (PD), are a significant global health challenge with no effective therapies to counteract neurodegeneration. Genetic and environmental factors lead to mitochondrial dysfunction and increased reactive oxygen species (ROS), resulting in oxidative stress. This stress reduces levels of Peroxiredoxin 3 (PRDX3), a key protein for maintaining ROS balance at the mitochondrial level, increasing the substantia nigra's susceptibility to damage. To investigate the protective role of antioxidant gene therapy in a PD model, we overexpressed the PRDX3 enzyme using a cell-penetrating peptide-based delivery system (mRVG9R-PRDX3 complex). The mRVG9R peptide was combined with a green fluorescent protein (GFP) reporter plasmid expressing PRDX3 to create the complex. Overexpression of the PRDX3 gene in neuronal phenotype cells was confirmed in vitro using dopaminergic SH-SY5Y cells. Following successful in vitro expression, the mRVG9R-PRDX3 complex was stereotaxically injected into the striatum of male C57BL/6 mice. The PD model was induced by administering paraquat (PQ) twice a week for 6 weeks. After the final PQ injection, motor and cognitive functions were evaluated, followed by histological analysis. Animals treated with the mRVG9R-PRDX3 complex showed a clear reduction in PQ-induced PD symptomatology and prevented cellular senescence in the substantia nigra's neuronal population. The mRVG9R-PRDX3 gene therapy improved motor and cognitive functions in the PD animal model and demonstrated potential in protecting substantia nigra dopaminergic neurons from PQ-induced death.

Pediatric Neuroimaging of Multiple Sclerosis and Neuroinflammatory Diseases

Using a pediatric-focused lens, this review article briefly summarizes the presentation of several demyelinating and neuroinflammatory diseases using conventional magnetic resonance imaging (MRI) sequences, such as T1-weighted with and without an exogenous gadolinium-based contrast agent, T2-weighted, and fluid-attenuated inversion recovery (FLAIR). These conventional sequences exploit the intrinsic properties of tissue to provide a distinct signal contrast that is useful for evaluating disease features and monitoring treatment responses in patients by characterizing lesion involvement in the central nervous system and tracking temporal features with blood-brain barrier disruption. Illustrative examples are presented for pediatric-onset multiple sclerosis and neuroinflammatory diseases. This work also highlights findings from advanced MRI techniques, often infrequently employed due to the challenges involved in acquisition, post-processing, and interpretation, and identifies the need for future studies to extract the unique information, such as alterations in neurochemistry, disruptions of structural organization, or atypical functional connectivity, that may be relevant for the diagnosis and management of disease.

The next frontier in multiple sclerosis therapies: Current advances and evolving targets

Recent advancements in research have significantly enhanced our comprehension of the intricate immune components that contribute to multiple sclerosis (MS) pathogenesis. By conducting an in-depth analysis of complex molecular interactions involved in the immunological cascade of the disease, researchers have successfully identified novel therapeutic targets, leading to the development of innovative therapies. Leveraging pioneering technologies in proteomics, genomics, and the assessment of environmental factors has expedited our understanding of the vulnerability and impact of these factors on the progression of MS. Furthermore, these advances have facilitated the detection of significant biomarkers for evaluating disease activity. By integrating these findings, researchers can design novel molecules to identify new targets, paving the way for improved treatments and enhanced patient care. Our review presents recent discoveries regarding the pathogenesis of MS, highlights their genetic implications, and proposes an insightful approach for engaging with newer therapeutic targets in effectively managing this debilitating condition.

Macular vascular density alteration patterns in paediatric optic neuritis patients with serum MOG antibody positivity detected by optic coherence tomography angiography

PURPOSE

The retinal microvascular network plays a crucial role in inflammatory injury in paediatric optic neuritis (PON) with serum MOG antibody positivity (MOG + PON). This study compared retinal microvascular densities and structural alterations in MOG + PON eyes with paediatric isolated optic neuritis (PION) eyes and followed up with the final best-corrected visual acuity (BCVA) after 6 months.

METHODS

A total of 29 children (52 eyes) with PON, including 15 MOG + PON cases (28 eyes), 6 PION cases (10 eyes), 2 neuromyelitis optica spectrum disorders associated PON(NMOSD-PON) cases (4 eyes), 6 MOG-associated disease (MOGAD) patients without ON-affected eyes (MOG + NPON) cases (10 eyes) and age- and gender-matched healthy controls (HCs) underwent superficial/deep retinal angiography density (SAD/DAD) by optical coherence tomography angiography (OCTA). Their BCVAs were followed up until 6 months after PON onsets.

RESULTS

MOG + PON cases had better final BCVAs than PION and NMOSD-ON. MOG + PON (35.7 ± 10.3 %) and PION (40.1 ± 10.3 %) eyes experienced severe SAD reductions in contrast to MOGAD+NPON (48.7 ± 5.2 %) and HCs eyes (55.6 ± 8.2 %). However, DAD in MOG + PON eyes (48.5 ± 9.2 %) and MOG + NPON eyes (53.1 ± 3.3 %) increased compared to HC eyes (45.7 ± 9.6 %; p = 0.028 and 0.009, respectively). SAD reduction occurred in acute PON and was detected as early as 2 weeks after PON onset.

CONCLUSIONS

MOG + PON eyes had better final BCVAs than PION eyes, which displayed superficial retinal microvascular perfusion reductions and deep microvascular perfusion increases. SAD could be a sensitive surrogate for PON attacks in children with MOGAD.

Optical coherence tomography angiography measurements in neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody disease: A systematic review and meta-analysis

PURPOSE

Neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are immune-mediated disorders that can often manifest with optic neuritis (ON) among other symptoms. Optical coherence tomography angiography (OCTA) is an emerging diagnostic method that can quantify retinal capillary blood flow and vessel density (VD), which have been shown to be affected in NMOSD and MOGAD. Hence, we aimed to systematically review the studies addressing retinal microvasculature using OCTA in these diseases.

DESIGN

Systematic review and meta-analysis.

METHODS

PubMed, EMBASE, and Web of Sciences were systematically searched to identify articles addressing OCTA measurements in patients with NMOSD or MOGAD. Following the data extraction, a meta-analysis was performed on the study population and OCTA types amongst at least two homogenous studies.

RESULTS

Twenty-two studies on NMOSD, MOGAD, or both were included. Parafoveal superficial retinal capillary plexus (SRCP) VD and radial peripapillary capillary (RPC) VD were diminished in NMOSD ON+ and NMOSD ON- groups compared to healthy controls (HCs). In addition, both the SRCP VD and RPC VD were significantly reduced in NMOSD ON+ compared to NMOSD ON-. However, meta-analysis for deep retinal capillary plexus (DRCP) did not show a significant difference between NMOSD patients and HCs, or among ON+ and ON- patients. Furthermore, there was no significant difference in foveal avascular zone (FAZ) area size between NMOSD patients and HCs. Regarding MOGAD, the meta-analysis showed decreased parafoveal SRCP VD and RPC VD in MOGAD ON+ patients compared to HCs. Comparing NMOSD ON+ and MOGAD ON+, a meta-analysis was conducted for RPC VD, which showed no significant difference between the two groups.

CONCLUSIONS

This systematic review and meta-analysis confirmed reduced VD in the macular and peripapillary areas in NMOSD and MOGAD eyes, particularly in the parafoveal SRCP and RPC, which is further impacted by prior ON.

Rapid differentiation of MOGAD and MS after a single optic neuritis

BACKGROUND

Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS) and myelin-oligodendrocyte-glycoprotein IgG-associated disease (MOGAD). This study evaluated the applicability of optical coherence tomography (OCT) for differentiating between both diseases in two independent cohorts.

METHODS

One hundred sixty two patients from seven sites underwent standard OCT and high-contrast visual acuity (HCVA) testing at least 6 months after first ON. Of these, 100 patients (32 MOGAD, 68 MS) comprised the primary investigational cohort, while 62 patients (31 MOGAD, 31 MS) formed a validation cohort. A composite score distinguishing between MOGAD and MS was developed using multivariate logistic regression.

RESULTS

Bilateral simultaneous ON occurred more frequently in MOGAD compared to MS (46.9 vs. 11.8%, p < 0.001). OCT revealed more peripapillary retinal nerve fiber layer (pRNFL) atrophy in all segments in MOGAD compared to predominantly temporal pRNFL atrophy in MS (p < 0.001). HCVA was better preserved in MS (p = 0.007). pRNFL thickness in all except for temporal segments was suitable for differentiating MOGAD and MS. Simultaneous bilateral ON and critical atrophy in nasal (< 58.5 µm) and temporal superior (< 105.5 µm) segments were included into the composite score as three independent predictors for MOGAD. The composite score distinguished MOGAD from MS with 75% sensitivity and 90% specificity in the investigational cohort, and 68% sensitivity and 87% specificity in the validation cohort.

CONCLUSION

Following a single ON-episode, MOGAD exhibits more pronounced global pRNFL atrophy and lower visual acuity after ON compared to MS. The introduced OCT-based composite score enabled differentiation between the two entities across both cohorts.

Cocaine taking and craving produce distinct transcriptional profiles in dopamine neurons

Dopamine (DA) signaling plays an essential role in reward valence attribution and in encoding the reinforcing properties of natural and artificial rewards. The adaptive responses from midbrain dopamine neurons to artificial rewards such as drugs of abuse are therefore important for understanding the development of substance use disorders. Drug-induced changes in gene expression are one such adaptation that can determine the activity of dopamine signaling in projection regions of the brain reward system. One of the major challenges to obtaining this understanding involves the complex cellular makeup of the brain, where each neuron population can be defined by a distinct transcriptional profile. To bridge this gap, we have adapted a virus-based method for labeling and capture of dopamine nuclei, coupled with nuclear RNA-sequencing, to study the transcriptional adaptations, specifically, of dopamine neurons in the ventral tegmental area (VTA) during cocaine taking and cocaine craving, using a mouse model of cocaine intravenous self-administration (IVSA). Our results show significant changes in gene expression across non-drug operant training, cocaine taking, and cocaine craving, highlighted by an enrichment of repressive epigenetic modifying enzyme gene expression during cocaine craving. Immunohistochemical validation further revealed an increase of H3K9me3 deposition in DA neurons during cocaine craving. These results demonstrate that cocaine-induced transcriptional adaptations in dopamine neurons vary by phase of self-administration and underscore the utility of this approach for identifying relevant phase-specific molecular targets to study the behavioral course of substance use disorders.

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.

A Case of Myelin Oligodendrocyte Glycoprotein Antibody Disease in a Pediatric Patient: Clinical Presentation, Treatment Response, and Follow-Up Considerations

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a rare autoimmune demyelinating disorder that targets the central nervous system and is characterized by antibodies that act against myelin oligodendrocyte glycoprotein (MOG). This disorder typically manifests with symptoms such as optic neuritis, transverse myelitis, or encephalitis, leading to symptoms such as vision loss, muscle weakness, sensory disturbances, and cognitive impairment. We present the case of a 10-year-old male who was eventually diagnosed with MOGAD after consideration of several other neurological and musculoskeletal disorders, who was admitted to the hospital due to an initial presentation of urinary retention and pelvic pain. The patient's clinical course included an MRI scan showing extensive demyelinating lesions in the spinal cord, along with positive MOG antibody serology. Management involved a multidisciplinary approach, including consultations from neurology, physical therapy, and the general pediatrics team, as well as administration of high-dose corticosteroids. This case underscores the importance of early recognition and aggressive treatment of MOGAD, a disorder that can present similarly to other demyelinating diseases such as multiple sclerosis and neuromyelitis optica spectrum disorder, with the distinguishing feature of MOGAD being the presence of antibodies against MOG.

Optic Neuritis Leading to Vision Loss: A Case of MOG-Associated Disease with Successful Immunotherapy

BACKGROUND Myelin oligodendrocyte glycoprotein (MOG)-associated disease (MOGAD) is a recently described inflammatory demyelinating disease of the central nervous system (CNS), which needs to be distinguished from aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG+NMOSD) and multiple sclerosis (MS). CASE REPORT A 42-year-old woman presenting with loss of vision due to optic neuritis was admitted to the Naval Medical Center in October 2022. She had optic disc edema, blurred visual margins, optic disc pallor, and deficient visual field in both eyes. Cranial magnetic resonance imaging (MRI) showed bilateral optic nerve thickening, tortuosity, and swelling, especially on the right side. Orbital MRI T2 sequence showed the typical "double track sign" change. The titers of MOG-IgG in CSF and serum were 1: 1 (+) and 1: 32 (+) separately, so MOGAD was diagnosed. The primary treatment was intravenous methylprednisolone for 2 weeks, after which the blurred vision improved and MRI showed the optic nerve lesions disappeared. She was discharged and oral corticosteroids were tapered gradually, and 1 month later, the symptom had vanished without recurrence, cranial MRI was normal, and MOG-IgG in CSF and serum were negative. Low-dose oral corticosteroids were continued for 6 months, with no relapse and normal cranial MRI, so we stopped corticosteroid therapy. At 1-year follow-up, the symptoms had not recurred. CONCLUSIONS A 42-year-old woman presented with loss of vision due to optic neuritis and positive antibody testing for MOG. MOGAD was diagnosed, and timely immunotherapy was effective.

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.

Combined Central and Peripheral Demyelination (CCPD) Associated with MOG Antibodies: Report of Four New Cases and Narrative Review of the Literature

Background/Objectives: Myelin oligodendrocyte glycoprotein (MOG) is exclusively expressed in the central nervous system (CNS) and is found on the outer surface of oligodendrocytes. Antibodies to MOG are associated with CNS demyelination, whereas peripheral nervous system (PNS) demyelination is seldom reported to be related to MOG-IgG. Methods: The database of patients seen in our neurological academic center was searched for MOG-IgG seropositivity and concomitant demyelinating polyneuropathy. For the purpose of the review, in March 2024, we searched for case reports and case series in the following databases: PubMed, Scopus, Cochrane, and ScienceDirect. Inclusion criteria were MOG-IgG seropositivity and demyelinating polyneuropathy. Exclusion criteria were type of publication other than case reports and case series, unconfirmed diagnosis of demyelinating polyneuropathy, and other diseases causing demyelination in either the CNS or PNS. Critical appraisal of the selected case reports and case series was realized by JBI. Results: Four new cases were identified with MOG-IgG and confirmed demyelinating polyneuropathy. This review identified 22 cases that have been published since 2018. Clinical, imaging, neurophysiological, and immunological characteristics, as well as treatment options and outcomes are presented and compared to those of other cases with combined central and peripheral demyelination (CCPD). Conclusions: The pathogenetic mechanism is unclear; thus, different hypotheses are discussed. New case reporting and large cohort studies will help further the exploration of the underlying mechanism and guide more effective therapeutic interventions.

Prevalence of anti-myelin oligodendrocyte glycoprotein antibodies across neuroinflammatory and neurodegenerative diseases

Inflammatory central nervous system (CNS) diseases, such as multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), are characterized by humoral immune abnormalities. Anti-MOG antibodies are not specific to MOGAD, with their presence described in MS. Autoantibodies may also be present and play a role in various neurodegenerative diseases. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease driven by motor neuron dysfunction. While immune involvement in ALS has been recognized, the presence of antibodies targeting CNS myelin antigens has not been established. We aimed to establish a live cell-based assay for quantification of serum anti-MOG IgG1 in patients with CNS diseases, including MS and ALS. In total, 771 serum samples from the John L. Trotter MS Center and the Northeast ALS Consortium were examined using a live cell-based assay for detection of anti-MOG IgG1. Samples from three cohorts were tested in blinded fashion: healthy control (HC) subjects, patients with clinically diagnosed MOGAD, and an experimental group of ALS and MS patients. All samples from established MOGAD cases were positive for anti-MOG antibodies, while all HC samples were negative. Anti-MOG IgG1 was detected in 65 of 658 samples (9.9%) from MS subjects and 4 of 108 (3.7%) samples from ALS subjects. The presence of serum anti-MOG IgG1 in MS and ALS patients raises questions about the contribution of these antibodies to disease pathophysiology as well as accuracy of diagnostic approaches for CNS inflammatory diseases.

Low T3 syndrome is associated with the severity of myelin oligodendrocyte glycoprotein antibody-associated disease exacerbation

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune inflammatory disease of the central nervous system, (CNS) different from multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). While numerous studies have delved into the involvement of thyroid antibodies (ATAbs) and thyroid function in NMOSD and MS. The objective of this study is to explore the clinical significance of thyroid dysfunction and ATAbs abnormalities in adult patients with MOGAD.

Methods

36 adult inpatients diagnosed with MOGAD and 47 sex- and age-matched healthy controls were enrolled. Patients were divided into two groups based on the presence or absence of low T3 syndrome. Demographics, clinical characteristics, and results of auxiliary examinations were compared across the subgroups. Moreover, an analysis was conducted to explore the correlations between thyroid hormone levels and Expanded Disability Status Scale (EDSS) scores.

Results

Thyroid dysfunction was notably more frequent in MOGAD patients than healthy controls (p < 0.0001), particularly low T3 syndrome (p=0.03). Furthermore, subgroup analyses revealed that the low T3 syndrome group exhibited higher EDSS scores and a higher proportion of individuals with EDSS scores > 3, in comparison to the non-low T3 syndrome group (p = 0.014, p = 0.046). However, no significant differences were observed in demographic characteristics, annual relapse rates, clinical phenotypes, laboratory and MRI results, and EEG abnormalities between the two groups. Additional Spearman's analysis showed significantly negative correlations between the TT3 and FT3 levels with EDSS scores (r = -0.367, p = 0.028; r = -0.377, p = 0.024). Typical brain lesions and paralateral ventricle lesions were significantly rare in patients with positive ATAbs compared to those with negative ATAbs (p = 0.0001, p = 0.03), although the incidence of ATAbs abnormalities did not differ significantly between MOGAD patients and healthy controls.

Conclusions

Overall, this study confirmed thyroid dysfunction, especially low T3 syndrome, is frequent in adult MOGAD patients. Patients with low T3 syndrome exhibited elevated EDSS scores and a significantly higher incidence of unfavorable condition. additionally, the correlation analysis model manifests that FT3 and TT3 levels were negatively correlated with EDSS scores. These evidences indicate that low T3 syndrome is associated with the severity of MOGAD exacerbation.

Serum NfL and EGFR/NfL ratio mRNAs as biomarkers for phenotype and disease severity of myelin oligodendrocyte glycoprotein IgG-associated disease

Background and purpose

Myelin oligodendrocyte glycoprotein (MOG) IgG is frequently elevated in pediatric patients with acquired demyelinating syndrome (ADS). However, no specific biomarkers exist for phenotype classification, symptom severity, prognosis, and treatment guidance of MOG-IgG-associated disease (MOGAD). This study evaluated neurofilament light chain (NfL) and endothelial growth factor receptor (EGFR) mRNA expression levels in serum and cerebrospinal fluid (CSF) as potential biomarkers for MOGAD in Chinese children.

Methods

This was a cross-sectional and single-center study. We enrolled 22 consecutive pediatric patients hospitalized with MOGAD and 20 control pediatric patients hospitalized for noninflammatory neurological diseases in Hebei Children's Hospital. Serum and CSF were collected from MOGAD patients within 3 days before immunotherapy. The mRNA levels of NfL and EGFR in serum and CSF were measured by real-time polymerase chain reaction (qPCR), and the EGFR/NfL ratio mRNA was calculated. These measurement values were then compared between disease groups and among MOGAD phenotypes. In addition, the correlations between the mRNAs of three markers (NfL, EGFR, EGFR/NfL ratio), extended disability status scale (EDSS) scores, and clinical phenotypes were analyzed.

Results

Serum and CSF NfL mRNA levels were significantly higher of acute-stage MOGAD patients than those of control patients (p< 0.05 and p< 0.01, respectively), while the mRNA levels of serum EGFR and EGFR/NfL ratio were significantly lower of MOGAD patients than those of controls (p < 0.05, p < 0.0001). Serum NfL mRNA was significantly correlated with mRNA of serum EGFR (r =0.480, p < 0.05). Serum and CSF NfL mRNA levels in MOGAD patients with the ADEM-like phenotype were also significantly higher than those in control patients (p < 0.01, p < 0.01) and optic neuritis (ON) phenotype (p < 0.05, p < 0.05). Both mRNAs of NfL in CSF and EGFR/NfL ratio in serum were correlated with EDSS scores (p < 0.05, r = 0.424; p < 0.05, r= -0.521).

Conclusion

The mRNA levels of elevated NfL in serum and CSF as well as lower EGFR and EGFR/NfL ratio in serum could help distinguish acute-phase MOGAD. Higher mRNA levels of NfL in serum and CSF of MOGAD patients help distinguish ADEM-like phenotype. In addition, serum EGFR/NfL mRNA ratio is indicative of disease severity in pediatric patients with MOGAD. Further investigations are warranted to elucidate the pathological mechanisms underlying these associations.

Proteome profile of the cerebellum from α7 nicotinic acetylcholine receptor deficient mice

The alpha7 nicotinic acetylcholine receptor (α7 nAChR; CHRNA7) is expressed in the nervous system and in non-neuronal tissues. Within the central nervous system, it is involved in various cognitive and sensory processes such as learning, attention, and memory. It is also expressed in the cerebellum, where its roles are; however, not as well understood as in the other brain regions. To investigate the consequences of absence of CHRNA7 on the cerebellum proteome, we performed a quantitative nano-LC-MS/MS analysis of samples from CHRNA7 knockout (KO) mice and corresponding wild type (WT) controls. Liver, an organ which does not express this receptor, was analyzed, in comparison. While the liver proteome remained relatively unaltered (three proteins more abundant in KOs), 90 more and 20 less abundant proteins were detected in the cerebellum proteome of the KO mice. The gene ontology analysis of the differentially abundant proteins indicates that the absence of CHRNA7 leads to alterations in the glutamatergic system and myelin sheath in the cerebellum. In conclusion, our dataset provides new insights in the role of CHRNA7 in the cerebellum, which may serve as a basis for future in depth-investigations.

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.

Immune System Dysregulation in the Progression of Multiple Sclerosis: Molecular Insights and Therapeutic Implications

Multiple sclerosis (MS), a prevalent neurological disorder, predominantly affects young adults and is characterized by chronic autoimmune activity. The study explores the immune system dysregulation in MS, highlighting the crucial roles of immune and non-neuronal cells in the disease's progression. This review examines the dual role of cytokines, with some like IL-6, TNF-α, and interferon-gamma (IFN-γ) promoting inflammation and CNS tissue injury, and others such as IL-4, IL-10, IL-37, and TGF-β fostering remyelination and protecting against MS. Elevated chemokine levels in the cerebrospinal fluid (CSF), including CCL2, CCL5, CXCL10, CXCL13, and fractalkine, are analyzed for their role in facilitating immune cell migration across the blood-brain barrier (BBB), worsening inflammation and neurodegeneration. The study also delves into the impact of auto-antibodies targeting myelin components like MOG and AQP4, which activate complement cascades leading to further myelin destruction. The article discusses how compromised BBB integrity allows immune cells and inflammatory mediators to infiltrate the CNS, intensifying MS symptoms. It also examines the involvement of astrocytes, microglia, and oligodendrocytes in the disease's progression. Additionally, the effectiveness of immunomodulatory drugs such as IFN-β and CD20-targeting monoclonal antibodies (e.g., rituximab) in modulating immune responses is reviewed, highlighting their potential to reduce relapse rates and delaying MS progression. These insights emphasize the importance of immune system dysfunction in MS development and progression, guiding the development of new therapeutic strategies. The study underscores recent advancements in understanding MS's molecular pathways, opening avenues for more targeted and effective treatments.

RNA velocity prediction via neural ordinary differential equation

RNA velocity is a crucial tool for unraveling the trajectory of cellular responses. Several approaches, including ordinary differential equations and machine learning models, have been proposed to interpret velocity. However, the practicality of these methods is constrained by underlying assumptions. In this study, we introduce SymVelo, a dual-path framework that effectively integrates high- and low-dimensional information. Rigorous benchmarking and extensive studies demonstrate that SymVelo is capable of inferring differentiation trajectories in developing organs, analyzing gene responses to stimulation, and uncovering transcription dynamics. Moreover, the adaptable architecture of SymVelo enables customization to accommodate intricate data and diverse modalities in forthcoming research, thereby providing a promising avenue for advancing our understanding of cellular behavior.

Transverse Myelitis: An Adverse Reaction to Abatacept

Immunotherapies are powerful disease-modifying agents in treating autoimmune diseases like rheumatoid arthritis (RA). However, their unique mechanisms of action confer a broad spectrum of immune-related adverse events (irAEs), which tend to be rare but complex, with significant risk for morbidity and mortality. We report a case of transverse myelitis in a patient with RA whose joint disease had been well-controlled with long-term intravenous abatacept. Suspicion of an unusual irAE in this elderly patient, whose neurologic symptomatology was gradual and protracted, prompted the discontinuation of abatacept and the rapid initiation of corticosteroid therapy. These interventions yielded a favorable clinical outcome for the patient. We must draw clinicians' attention to this rare but potentially consequential adverse drug reaction.

Clinical and radiographic features of a cohort of adult and pediatric subjects in the Pacific Northwest with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a newly described clinical entity comprised of isolated or recurrent attacks of optic neuritis, transverse myelitis, acute disseminated encephalomyelitis (ADEM), encephalitis, or seronegative NMOSD. Prior studies report that 30-80 % of children and adults with MOGAD go on to have relapses though there are no reliable predictors. The objectives of this study were to (1) describe the demographic, clinical, and radiographic patterns of MOGAD at our center and (2) identify possible predictors of relapsing disease.

METHODS

Single-center retrospective cohort study of pediatric and adult subjects with MOGAD evaluated at least once at our center between January 1, 2017 and September 30, 2022. Eligible subjects had a history of positive MOG-IgG and consistent clinical syndrome comprised of an initial attack of optic neuritis (ON), transverse myelitis (TM), ADEM, cerebral cortical encephalitis, seronegative neuromyelitis optica (simultaneous ON and TM), isolated brainstem or cerebellar syndrome, or other (not fitting into another group). Relapsing subjects or those remaining monophasic at 12 months were included in the analyses of predictors of relapsing disease. Covariates included age, sex, race/ethnicity, and index event phenotype. Unadjusted and adjusted risk ratios were calculated for pediatric and adult subjects.

RESULTS

We describe the demographic, clinical, and radiographic characteristics of 58 subjects with MOGAD. Covariates from 48 subjects were analyzed for predictors of relapsing disease. In adults, Hispanics and non-White non-Hispanics were at increased risk of relapsing disease compared to non-Hispanic Whites [Adjusted RR 1.52 (95 % CI: 1.01, 2.30)]. There were no significant associations in the pediatric group.

CONCLUSION

This study is the first to describe a cohort of MOGAD in the Pacific Northwest. Our findings highlight racial and ethnic differences in risk of relapsing MOGAD in adults. Further studies on racial and ethnic differences in MOGAD are needed to confirm these findings.

Role of Specific Autoantibodies in Neurodegenerative Diseases: Pathogenic Antibodies or Promising Biomarkers for Diagnosis

Neurodegenerative diseases (NDDs) affect millions of people worldwide. They develop due to the pathological accumulation and aggregation of various misfolded proteins, axonal and synaptic loss and dysfunction, inflammation, cytoskeletal abnormalities, defects in DNA and RNA, and neuronal death. This leads to the activation of immune responses and the release of the antibodies against them. Recently, it has become clear that autoantibodies (Aabs) can contribute to demyelination, axonal loss, and brain and cognitive dysfunction. This has significantly changed the understanding of the participation of humoral autoimmunity in neurodegenerative disorders. It is crucial to understand how neuroinflammation is involved in neurodegeneration, to aid in improving the diagnostic and therapeutic value of Aabs in the future. This review aims to provide data on the immune system's role in NDDs, the pathogenic role of some specific Aabs against molecules associated with the most common NDDs, and their potential role as biomarkers for monitoring and diagnosing NDDs. It is suggested that the autoimmune aspects of NDDs will facilitate early diagnosis and help to elucidate previously unknown aspects of the pathobiology of these diseases.

Epstein-Barr Virus and Human Endogenous Retrovirus in Japanese Patients with Autoimmune Demyelinating Disorders

Multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocytes glycoprotein-antibody disease (MOGAD) are distinct autoimmune demyelinating disorders characterized by varying clinical and pathological characteristics. While the precise origins of these diseases remain elusive, a combination of genetic and environmental factors, including viral elements, have been suggested as potential contributors to their development. Our goal was to assess the occurrence of antibodies against pathogenic peptides associated with Epstein-Barr virus (EBV) and the human endogenous retrovirus-W (HERV-W) in serum samples obtained from Japanese individuals diagnosed with MS, NMOSD, and MOGAD and to make comparisons with a group of healthy controls (HCs). We conducted a retrospective analysis involving 114 Japanese participants, comprising individuals with MS (34), NMOSD (20), MOGAD (20), and HCs (40). These individuals were tested using a peptide-based enzyme-linked immunosorbent assay. A marked increase in antibody response against EBV nuclear antigen 1 (EBNA1)386-405 was observed in the serum of MS and MOGAD patients, as compared to HCs. Notably, we observed a correlation between antibodies against EBNA1386-405 and HERV-W486-504 peptides in a subset of the antibody-positive MS patients. These findings emphasize the involvement of EBV in the pathogenesis of MS and potentially MOGAD, suggesting its role in the reactivation of HERV-W.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease and COVID-19: A Systematic Review

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an uncommon neurological disease affecting the central nervous system (CNS). Numerous neurological disorders, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), acute transverse myelitis (ATM), and MOGAD, have been reported following the COVID-19 infection during the current COVID-19 pandemic. On the other hand, it has been suggested that patients with MOGAD may be at greater risk for infection (particularly in the current pandemic).

Objective

In this systematic review, we gathered separately 1) MOGAD cases following COVID-19 infection as well as 2) clinical course of patients with MOGAD infected with COVID-19 based on case reports/series.

Methods

329 articles were collected from 4 databases. These articles were conducted from inception to March 1st, 2022.

Results

Following the screening, exclusion criteria were followed and eventually, 22 studies were included. In 18 studies, a mean ± SD time interval of 18.6 ± 14.9 days was observed between infection with COVID-19 and the onset of MOGAD symptoms. Symptoms were partially or completely recovered in a mean of 67 days of follow-up. Among 4 studies on MOGAD patients, the hospitalization rate was 25%, and 15% of patients were hospitalized in the intensive care unit (ICU).

Conclusion

Our systematic review demonstrated that following COVID-19 infection, there is a rare possibility of contracting MOGAD. Moreover, there is no clear consensus on the susceptibility of MOGAD patients to severe COVID-19. However, obtaining deterministic results requires studies with a larger sample size.

Neuromyelitis Optica: Pathogenesis Overlap with Other Autoimmune Diseases

PURPOSE OF REVIEW

Neuromyelitis optica (NMO) is an auto-immune disease essentially depicted by optic neuritis and transverse myelitis. Per se, NMO was initially believed to be a sub-type of multiple sclerosis with typical demyelinating cerebral lesions and optic nerve inflammation. More recently, corroborating lignes of evidence have strengthened the concept of the spectrum of diseases associated with NMO and more specifically with the role of anti-aquaporin-4 antibodies in the pathogenesis of disease.

RECENT FINDINGS

In this article, we review the recent pathogenic findings in NMO and more interestingly the newly discovered role of anti-aquaporin-4 antibodies as key players in triggering cerebral lesions. The concept of spectrum of diseases associated with NMO is also discussed. These recent findings have paved in the further understanding of the pathogenesis underlying NMO and new treatments are currently being developed targeting anti-aquaporin-4 antibodies.

Pro-myelinating clemastine administration improves recording performance of chronically implanted microelectrodes and nearby neuronal health

Intracortical microelectrodes have become a useful tool in neuroprosthetic applications in the clinic and to understand neurological disorders in basic neurosciences. Many of these brain-machine interface technology applications require successful long-term implantation with high stability and sensitivity. However, the intrinsic tissue reaction caused by implantation remains a major failure mechanism causing loss of recorded signal quality over time. Oligodendrocytes remain an underappreciated intervention target to improve chronic recording performance. These cells can accelerate action potential propagation and provides direct metabolic support for neuronal health and functionality. However, implantation injury causes oligodendrocyte degeneration and leads to progressive demyelination in surrounding brain tissue. Previous work highlighted that healthy oligodendrocytes are necessary for greater electrophysiological recording performance and the prevention of neuronal silencing around implanted microelectrodes over the chronic implantation period. Thus, we hypothesize that enhancing oligodendrocyte activity with a pharmaceutical drug, Clemastine, will prevent the chronic decline of microelectrode recording performance. Electrophysiological evaluation showed that the promyelination Clemastine treatment significantly elevated the signal detectability and quality, rescued the loss of multi-unit activity, and increased functional interlaminar connectivity over 16-weeks of implantation. Additionally, post-mortem immunohistochemistry showed that increased oligodendrocyte density and myelination coincided with increased survival of both excitatory and inhibitory neurons near the implant. Overall, we showed a positive relationship between enhanced oligodendrocyte activity and neuronal health and functionality near the chronically implanted microelectrode. This study shows that therapeutic strategy that enhance oligodendrocyte activity is effective for integrating the functional device interface with brain tissue over chronic implantation period.

An update on optic neuritis

Optic neuritis (ON) is the most common cause of subacute optic neuropathy in young adults. Although most cases of optic neuritis (ON) are classified as typical, meaning idiopathic or associated with multiple sclerosis, there is a growing understanding of atypical forms of optic neuritis such as antibody mediated aquaporin-4 (AQP4)-IgG neuromyelitis optica spectrum disorder (NMOSD) and the recently described entity, myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). Differentiating typical ON from atypical ON is important because they have different prognoses and treatments. Findings of atypical ON, including severe vision loss with poor recovery with steroids or steroid dependence, prominent optic disc edema, bilateral vision loss, and childhood or late adult onset, should prompt serologic testing for AQP4-IgG and MOG-IgG. Although the traditional division of typical and atypical ON can be helpful, it should be noted that there can be severe presentations of otherwise typical ON and mild presentations of atypical ON that blur these traditional lines. Rare causes of autoimmune optic neuropathies, such as glial fibrillary acidic protein (GFAP) and collapsin response-mediator protein 5 (CRMP5) autoimmunity also should be considered in patients with bilateral painless optic neuropathy associated with optic disc edema, especially if there are other accompanying suggestive neurologic symptoms/signs. Typical ON usually recovers well without treatment, though recovery may be expedited by steroids. Atypical ON is usually treated with intravenous steroids, and some forms, such as NMOSD, often require plasma exchange for acute attacks and long-term immunosuppressive therapy to prevent relapses. Since treatment is tailored to the cause of the ON, elucidating the etiology of the ON is of the utmost importance.

The Role of MRI in the Diagnosis of Spinal Cord Tumors

Spinal cord tumors are uncommon, and its multiple representatives not always have pathognomonic characteristics, which poses a challenge for both patients and caring physicians. The radiologist performs an important role in recognizing these tumors, as well as in differentiating between neoplastic and non-neoplastic processes, supporting clinical and surgical decision-making in patients with spinal cord injury. Magnetic Resonance Imaging (MRI) assessment, paired with a deep understanding of the various patterns of cord involvement allied to detailed clinical data can provide a diagnosis or significantly limit the differential diagnosis in most cases. In this article, we aim to review the most common and noteworthy intramedullary and extramedullary spinal tumors, as well as some other tumoral mimics, with an emphasis on their MRI morphologic characteristics.

The immune imbalance between follicular regulatory and helper T cells in myelin oligodendrocyte glycoprotein IgG-associated disease

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a newly defined inflammatory demyelinating disease of the central nervous system. Currently, no immuno-modulatory treatment has been approved for MOGAD. We explored the function of follicular regularoty T (Tfr) and follicular helper T (Tfh) cells in patients with MOGAD. The number of circulating Tfr and Tfh cells and their expression of functional markers were accessed by flow cytometry. Circulating Tfr, Tfh, and B cells were further sorted and co-cultured in vitro to examine the influence of Tfr on Tfh-mediated B cell differentiation. In patients with MOGAD, the percentage of circulating PD-1hi Tfh cells elevated while the frequency of circulating activated Tfr cells decreased significantly. The Tfh/Tfr ratios positively correlated with the percentage of plasmblasts. In vitro, Tfh cells from patients with MOGAD exhibited a stronger capacity to promote the differentiation of plasmablasts through producing interleukin (IL)-21 than non-Tfh cells from patients, whereas Tfr cells suppressed this Tfh-mediated plasmablasts expansion, to a similar extent of IL-1 receptor antagonist (IL-1Ra). In conclusion, we revealed an immune imbalance of Tfr and Tfh cells in MOGAD. Tfr and IL-1Ra could be potential therapeutic targets in MOGAD.

A case report of neurosyphilis coexisting with a positive MOG antibody manifested as optic neuritis

Background

Neurosyphilis refers to an infection of the central nervous system by Treponema pallidum. The clinical manifestations of neurosyphilis are diverse, making it easy to miss or misdiagnose. Anti-myelin oligodendrocyte glycoprotein antibody-associated disease is a recently defined immune-mediated inflammatory demyelinating central nervous system disease. Few studies have reported the coexistence of the two diseases.

Case presentation

This case report presents a 37 years-old male patient with neurosyphilis manifested as optic neuritis with a positive myelin oligodendrocyte glycoprotein (MOG) antibody. This patient received intravenous administration of 3.2 million units of procaine penicillin every 4 h for 2 weeks, followed by a two-week intramuscular injection of benzathine penicillin. Additionally, methylprednisolone sodium succinate was administered intravenously at 1,000 mg/day, gradually reduced to 500 mg/day and 240 mg/day every 3 days. Subsequently, prednisone tablets at a dosage of 60 mg/day were orally administered, with a gradual reduction of 5 mg/day every 3 days until reaching a dosage of 30 mg/day. The patient's visual acuity was improved after 26 days of hospitalization. However, the visual field and color vision did not. At 3 months of follow-up, the symptoms remained unchanged despite the patient continued taking oral prednisone tablets at a dosage of 30 mg/day.

Conclusion

Neurosyphilis could be a potential triggering factor for MOGAD. In patients with neurosyphilis, it is strongly recommended to perform testing for MOG antibody along with other brain disease antibodies.

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.

Patient Pathway to Diagnosis of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD): Findings from a Multinational Survey of 204 Patients

INTRODUCTION

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare demyelinating disorder of the central nervous system. Despite increased recognition of MOGAD as a distinct disease and the availability of sensitive methods of MOG antibody testing, diagnostic challenges remain. We conducted a survey to explore the patient experience from the start of symptoms to final MOGAD diagnosis.

METHODS

A 23-question online survey (including multiple-choice and free-text responses) covering symptom history, healthcare interactions and impact of diagnosis was emailed to people living with MOGAD by The MOG Project patient advocacy group. People living with MOGAD could share the survey with their caregivers. Anonymised responses were analysed.

RESULTS

In total, 204 people living with MOGAD or their caregivers from 21 countries completed the survey; most respondents were from North America. Age of symptom onset ranged from 1 to 66 (median 28) years. Symptoms that prompted patients to seek medical care included blurred vision/loss of vision (58.2%), eye pain (35.8%) and difficulty walking (25.4%). Patients most frequently presented to emergency care physicians (38.7%) and primary care doctors (26.0%), with the MOGAD diagnosis most often made by general neurologists (40.4%) or neuro-immunologists (30.0%). Patients saw a median of four doctors before diagnosis, with 26.5% of patients seeing at least six doctors. Although 60.6% of patients received a MOGAD diagnosis within 6 months of experiencing initial health problems, 17.7% experienced a ≥ 5-year delay. More than half of patients (55.4%) received an alternative primary diagnosis before final MOGAD diagnosis. Most respondents (60.6%) reported receiving insufficient information/resources at the time of MOGAD diagnosis. Diagnostic delay was associated with long-term negative consequences for physical health.

CONCLUSION

This survey provides unique insights from people living with MOGAD and their caregivers that could help address the challenges faced in the pathway to final MOGAD diagnosis.

Transverse myelitis in myelin oligodendrocyte glycoprotein antibody-associated disease

Transverse myelitis (TM) is the second most common presentation of myelin oligodendrocyte antibody-associated disease (MOGAD), occurring in approximately 26% of affected patients. The diagnosis may be complicated by the lack of diagnostic specificity of low titers of MOG antibody in serum, fluctuation in seropositivity overtime, including initially normal MRI in up to 10% of patients, and in many instances complete resolution of radiological abnormalities when MRI is done in a significantly delayed fashion. The use of preventive disease modifying treatments is limited by the uncertainty whether the disease process will remain monophasic or become relapsing, as well as by the lack FDA approved treatments. In this review, we discuss clinical, radiological and cerebrospinal fluid (CSF) characteristics, including the significance of MOG titers and changes in the seropositivity status for the diagnosis of MOGAD-associated TM, its radiological features and management options, highlighting the data on the risk of relapses associated with TM at presentation and the need for further randomized clinical trials to empower effective treatment algorithms.

The immunomodulatory roles of the gut microbiome in autoimmune diseases of the central nervous system: Multiple sclerosis as a model

The gut-associated lymphoid tissue is a primary activation site for immune responses to infection and immunomodulation. Experimental evidence using animal disease models suggests that specific gut microbes significantly regulate inflammation and immunoregulatory pathways. Furthermore, recent clinical findings indicate that gut microbes' composition, collectively named gut microbiota, is altered under disease state. This review focuses on the functional mechanisms by which gut microbes promote immunomodulatory responses that could be relevant in balancing inflammation associated with autoimmunity in the central nervous system. We also propose therapeutic interventions that target the composition of the gut microbiota as immunomodulatory mechanisms to control neuroinflammation.

Myelin Oligodendrocyte Glycoprotein as an Autoantigen in Inflammatory Demyelinating Diseases of the Central Nervous System

Demyelinating diseases of the central nervous system are caused by an autoimmune attack on the myelin sheath surrounding axons. Myelin structural proteins become antigenic, leading to the development of myelin lesions. The use of highly specialized laboratory diagnostic techniques for identification of specific antibodies directed against myelin components can significantly improve diagnostic approaches. Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) currently includes demyelinating syndromes with known antigens. Based on the demonstrated pathogenic role of human IgG against MOG, MOGAD was classified as a distinct nosological entity. However, generation of multiple MOG isoforms by alternative splicing hinders antigen detection even with the most advanced immunofluorescence techniques. On the other hand, MOG conformational changes ensure the structural integrity of other myelin proteins and maintain human-specific mechanisms of immune autotolerance.

The Coexistence of Antibodies to Neuronal Cell and Synaptic Receptor Proteins, Gangliosides and Selected Neurotropic Pathogens in Neurologic Disorders in Children

Various primarily non-autoimmune neurological disorders occur synchronously with autoantibodies against tissues in the nervous system. We aimed to assess serum and cerebrospinal fluid (CSF) autoantibodies in children with neurologic disorders. To find new diagnostic tools, we compared the laboratory and clinical findings between the distinguished groups. Retrospectively, 508 patients were divided into six subgroups: neuroinfections, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections, neurologic autoimmune and demyelinating diseases, epilepsy, pervasive developmental disorders and other patients. We analysed serum anti-aquaporin-4, antiganglioside, neuronal antinuclear and cytoplasmic antibodies, as well as antibodies against surface neuronal and synaptic antigens in the CSF and serum. We involved available demographic and clinical data. Autoantibodies appeared in 165 (32.3%) children, with 24 showing multiple types of them. The most common were anti-neuroendothelium (anti-NET), anti-N-Methyl-D-Aspartate receptor (anti-NMDAr), anti-glial fibrillary acidic protein and anti-myelin antibodies bothering 46/463 (9.9%), 32/343 (9.4%), 27/463 (5.8%) and 27/463 (5.8%), respectively. Anti-NET and anti-NMDAr antibodies appeared more frequently in children with autoimmunity (p = 0.017; p < 0.001, respectively), increasing the autoimmune disease risk (OR = 2.18, 95% CI 1.13–13.97; OR = 3.91, 95% CI 1.86–8.22, respectively). Similar pathomechanisms appeared in diseases of different aetiology with clinical spectrums mimicking each other, so we proposed the model helping to diagnose autoimmune disease. We proved the influence of age, living place and medical history on the final diagnosis.

B cell targeted therapies in inflammatory autoimmune disease of the central nervous system

Cumulative evidence along several lines indicates that B cells play an important role in the pathological course of multiple sclerosis (MS), neuromyelitisoptica spectrum disorders (NMOSD) and related CNS diseases. This has prompted extensive research in exploring the utility of targeting B cells to contain disease activity in these disorders. In this review, we first recapitulate the development of B cells from their origin in the bone marrow to their migration to the periphery, including the expression of therapy-relevant surface immunoglobulin isotypes. Not only the ability of B cells to produce cytokines and immunoglobulins seems to be essential in driving neuroinflammation, but also their regulatory functions strongly impact pathobiology. We then critically assess studies of B cell depleting therapies, including CD20 and CD19 targeting monoclonal antibodies, as well as the new class of B cell modulating substances, Bruton´s tyrosinekinase (BTK) inhibitors, in MS, NMOSD and MOGAD.

Clinical and Radiologic Features Among Children With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Myelitis

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) often manifests as optic neuritis, transverse myelitis(TM), and acute disseminated encephalomyelitis. Patients with a TM phenotype are at high risk for neurological sequelae, so recognizing the characteristics of MOG-IgG myelitis is essential for early, accurate diagnosis and treatment.

METHODS

This was a single-center retrospective study. Pediatric MOG antibody-associated disease patients who had clinical myelitis were recruited for this study. Data on clinical and radiologic features and outcomes were retrospectively collected.

RESULTS

Thirty-four patients (age range: 6 months to 13 years; median age, 7 years; female, 16) were enrolled in this study. As one patient had two clinical episodes of myelitis, 35 episodes were included. Isolated transverse myelitis was the initial manifestation in 28 (82%) patients. The most frequent clinical features of MOG-IgG myelitis were weakness and neurogenic bladder, and 80% were better than wheelchair-dependent at the nadir. There was a high presentation of weakness (91%), bowel/bladder dysfunction (63%), and sensory dysfunction (46%), and 80% were better than wheelchair-dependent at the nadir. In addition, seven patients (20%) had radicular pain, and six had flaccid areflexia. Magnetic resonance imaging features were often longitudinally extensive (63%) and prominently involved gray matter (H-sign) (63%), accompanied by leptomeningeal enhancement (4/14.29%) and spinal root enhancement (6/14.43%). At the final follow-up (median, 28 months; range, 8-109 months), 10 patients (29%) had developed one or more relapses, spinal cord lesions resolved entirely in 11 of 22 children (50%), and none had appreciable spinal cord atrophy. At the final follow-up, most patients had favorable outcomes, with median (interquartile range) Expanded Disability Status Scale scores of 0 (range, 0-2), four patients (12%) had sphincter dysfunction, and one patient had gait problems.

CONCLUSIONS

Pediatric MOG-IgG myelitis clinically presents with weakness and bowel and bladder dysfunctions. Prominent involvement of the gray matter, leptomeningeal enhancement, and spinal root enhancement are common in pediatric MOG-IgG myelitis.

Meta-analysis of the effectiveness of relapse prevention therapy for myelin-oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Approximately 40% of adults and 30% of children with Myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) experience a relapsing course, but the optimal relapse prevention therapy remains unclear. A meta- analysis was conducted to investigate the efficacy of azathioprine (AZA), mycophenolate mofetil (MMF), rituximab (RTX), maintenance intravenous immunoglobulin (IVIG), and tocilizumab (TCZ) in prevention of attacks in MOGAD.

METHODS

English and Chinese-language articles published from January 2010 to May 2022 were searched in PubMed, Embase, Web of Science, Cochrane, Wanfang Data, China National Knowledge Infrastructure (CNKI), and China Science and Technology Journal Database (CQVIP). Studies with fewer than three cases were excluded. Meta-analysis of the relapse-free rate, the change of annualized relapse rate (ARR)and Expanded Disability Status Scale (EDSS) scores before and after treatment, and an age subgroup analysis was performed.

RESULTS

A total of 41 studies were included. Three were prospective cohort studies, one was an ambispective cohort study, and 37 were retrospective cohort studies or case series. Eleven, eighteen, eighteen, eight, and two studies were included in the meta-analysis for relapse-free probability after AZA, MMF, RTX, IVIG, and TCZ therapy, respectively. The proportions of patients without relapse after AZA, MMF, RTX, IVIG, and TCZ were 65% [95% confidence interval (CI):49%-82%]), 73% (95%CI:62%-84%), 66% (95%CI:55%-77%), 79% (95%CI:66%-91%), and 93% (95%CI:54%-100%), respectively. The relapse-free rate did not significantly differ between the children and adults treated with each medication. Six, nine, ten, and three studies were included in the meta-analysis for the change of ARR before and after AZA, MMF, RTX, and IVIG therapy, respectively. ARR was significantly decreased after AZA, MMF, RTX, and IVIG therapy with a mean reduction of 1.58 (95%CI: [-2.29--0.87]), 1.32 (95%CI: [-1.57--1.07]), 1.01 (95%CI: [-1.34--0.67]), and 1.84 (95%CI: [-2.66--1.02]), respectively. The change in ARR did not significantly differ between children and adults.

CONCLUSIONS

AZA, MMF, RTX, maintenance IVIG, and TCZ all reduce the risk of relapse in both pediatric and adult patients with MOGAD. The literatures included in the meta-analysis were mainly retrospective studies, so large randomized prospective clinical trials are needed to compare the efficacy of different treatments.

Pro-myelinating Clemastine administration improves recording performance of chronically implanted microelectrodes and nearby neuronal health

Intracortical microelectrodes have become a useful tool in neuroprosthetic applications in the clinic and to understand neurological disorders in basic neurosciences. Many of these brain-machine interface technology applications require successful long-term implantation with high stability and sensitivity. However, the intrinsic tissue reaction caused by implantation remains a major failure mechanism causing loss of recorded signal quality over time. Oligodendrocytes remain an underappreciated intervention target to improve chronic recording performance. These cells can accelerate action potential propagation and provides direct metabolic support for neuronal health and functionality. However, implantation injury causes oligodendrocyte degeneration and leads to progressive demyelination in surrounding brain tissue. Previous work highlighted that healthy oligodendrocytes are necessary for greater electrophysiological recording performance and the prevention of neuronal silencing around implanted microelectrodes over chronic implantation. Thus, we hypothesize that enhancing oligodendrocyte activity with a pharmaceutical drug, Clemastine, will prevent the chronic decline of microelectrode recording performance. Electrophysiological evaluation showed that the promyelination Clemastine treatment significantly elevated the signal detectability and quality, rescued the loss of multi-unit activity, and increased functional interlaminar connectivity over 16-weeks of implantation. Additionally, post-mortem immunohistochemistry showed that increased oligodendrocyte density and myelination coincided with increased survival of both excitatory and inhibitory neurons near the implant. Overall, we showed a positive relationship between enhanced oligodendrocyte activity and neuronal health and functionality near the chronically implanted microelectrode. This study shows that therapeutic strategy that enhance oligodendrocyte activity is effective for integrating the functional device interface with brain tissue over chronic implantation period.

Abstract Figure

ATP line splitting in association with reduced intracellular magnesium and pH: a brain 31 P MR spectroscopic imaging (MRSI) study of pediatric patients with myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGADs)

Over the past four decades, ATP, the obligatory energy molecule for keeping all cells alive and functioning, has been thought to contribute only one set of signals in brain ³¹ P MR spectra. Here we report for the first time the observation of two separate β-ATP peaks in brain spectra acquired from patients with myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGADs) using 3D MRSI at 7 T. In voxel spectra with β-ATP line splitting, these two peaks are separated by 0.46 ± 0.18 ppm (n = 6). Spectral lineshape analysis indicates that the upper field β-ATP peak is smaller in relative intensity (24 ± 11% versus 76 ± 11%), and narrower in linewidth (56.8 ± 10.3 versus 41.2 ± 10.3 Hz) than the downfield one. Data analysis also reveals a similar line splitting for the intracellular inorganic phosphate (P_i ) signal, which is characterized by two components with a smaller separation (0.16 ± 0.09 ppm) and an intensity ratio (26 ± 7%:74 ± 7%) comparable to that of β-ATP. While the major components of P_i and β-ATP correspond to a neutral intracellular pH (6.99 ± 0.01) and a free Mg²⁺ level (0.18 ± 0.02 mM, by Iotti's conversion formula) as found in healthy subjects, their minor counterparts relate to a slightly acidic pH (6.86 ± 0.07) and a 50% lower [Mg²⁺ ] (0.09 ± 0.02 mM), respectively. Data correlation between β-ATP and P_i signals appears to suggest an association between an increased [H⁺ ] and a reduced [Mg²⁺ ] in MOGAD patients.

Unilateral Autoimmune Encephalitis: A Case Report on a Rare Manifestation of Myelin Oligodendrocyte Glycoprotein Antibody Disease

Myelin oligodendrocyte glycoprotein (MOG)-associated disease (MOGAD) is a rare, antibody-mediated inflammatory demyelinating disorder of the central nervous system (CNS) that has varying phenotypes. FLAIR (fluid-attenuated inversion recovery)-hyperintense Lesions in Anti-MOG-associated Encephalitis with Seizures (FLAMES) is a much rarer manifestation of cortical encephalitis encountered in MOGAD. We report a rare case of a nine-year-old girl who presented with a drop in her academic performance and right-sided Epilepsia partialis continua. Magnetic resonance imaging (MRI) of the brain detected evidence for unilateral (left) cortical encephalitis with peri-ictal juxtacortical edema. An electroencephalogram revealed a hemi-generalized poly spike and wave discharges in the left hemisphere, several of which correlated with myoclonic jerks. The cerebrospinal fluid (CSF) analysis was normal. Autoimmune workup resulted in a positive serum MOG-immunoglobulin G (IgG), which confirmed the diagnosis of FLAMES. The child showed an excellent clinical response to intravenous methylprednisolone and intravenous immunoglobulins therapy.

Reactivity to neural tissue epitopes, aquaporin 4 and heat shock protein 60 is associated with activated immune-inflammatory pathways and the onset of delirium following hip fracture surgery

OBJECTIVES

Activation of the immune-inflammatory response system (IRS) and a deficiency in the compensatory immunoregulatory system (CIRS), neuronal injuries, and alterations in the glutamate receptor (GlutaR), aquaporin-4 (AQP4) and heat shock protein 60 (HSP60) are involved in delirium. Increased serum levels of neurofilament protein (NFP), glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) are biomarkers of neuronal injury. This investigation delineates whether elevated IgA/IgG reactivity against those self-antigens is associated with delirium severity and IRS activation.

METHODS

We measured peak Delirium Rating Scale (DRS) scores on days 2 and 3 following surgery in 59 hip fractured older adults, and IgA and IgG antibody levels against MBP, NFP, GFAP and myelin oligodendrocyte glycoprotein (MOG), metabotropic glutamate receptors mGluRs 1 and 5, N-Methyl-D-Aspartate receptor (NMDAR) GLU₁ (NR₁) and GLU₂ (NR₂), APQ4 and HSP60.

RESULTS

The IgA antibody levels against those self-antigens, especially GFAP, MBP and HSP60, strongly predict peak DRS scores on days 2 and 3 post-surgery. IgA reactivity against NMDAR and baseline DRS scores explained 40.6% of the variance in peak DRS scores, while IgA against NMDAR, IgG against MBP and age explained 29.1% of the variance in the IRS/CIRS ratio. There was no correlation between DRS scores and IgG directed against other self-antigens.

CONCLUSIONS

Increased IgA levels against neuronal self-antigens, AQP4 and HSP60 are risk factors for delirium. Polyreactive antibody-associated breakdown of immune tolerance, IRS activation and injuries in the neuronal cytoskeleton, oligodendrocytes, astrocytes, glial cells, and myelin sheath are involved in the pathophysiology of delirium.

Clinical characteristic of myelin oligodendrocyte glycoprotein antibody associated cortical encephalitis in adults and outcomes following glucocorticoid therapy

Objective

To describe the clinical and radiological features, as well as outcomes following glucocorticoid therapy and recurrence in adults suffering from cortical encephalitis associated with myelin oligodendrocyte glycoprotein (MOG) antibody.

Methods

The clinical information of nine adult patients suffering from cortical encephalitis associated with MOG antibody admitted to the Affiliated Brain Hospital of Nanjing Medical University from 2020 to 2022 was systematically reviewed. The clinical symptoms, laboratory data, imaging results, outcomes following glucocorticoid therapy and recurrence were evaluated.

Result

A total of 9 patients positive for MOG antibody and suffering from cortical encephalitis were included in our study (55.6% men, median age 29 years, 15-57 years). The most common clinical symptoms included headache (77.8%), fever (66.7%), and generalized seizures (55.6%). Some patients also experienced limb shaking (22.2%), leg numbness (22.2%), transient motor aphasia (11.1%), and vision loss (11.1%). The main features of cerebrospinal fluid () examination were increased intracranial pressure, pleocytosis, and elevated cerebrospinal fluid (CSF) protein. In addition, N-methyl-D-aspartate receptor (NMDAR) and MOG antibodies were found in the CSF of 3 patients, and NMDAR, MOG, and glial fibrillary acidic protein antibodies were found in the CSF of 1 patient. All patients were subjected to magnetic resonance imaging (MRI) and the images of eight of them showed T2 and/flair image hyperintense lesions, three showed meningeal or lesion enhancement and four showed white matter lesions, which were mostly located in the midline structures (75%). All patients received glucocorticoid therapy in the acute phase and in remission, and eight of them received an intravenous high dose of methylprednisolone, including one patient who received a simultaneous immunoglobulin therapy. One patient was treated with low-dose prednisolone tablets. Seven (77.8%) patients were wholly recovered at discharge, and 2 (22.2%) patients were left with slight symptoms. During the median 9-month follow-up (range: 2-36 months), 2 (22.2%) patients developed recurrence.

Conclusion

The clinical manifestations of adult MOG antibody-associated cortical encephalitis were significantly different from those of the typical MOG antibody-associated disease (MOGAD). Patients in the acute phase of the disease were prone to show signs similar to central nervous system infection, requiring clinicians to have the ability to recognize the disease to avoid misdiagnosis. In addition, seizures were common in MOG antibody-related encephalitis, and the type of seizures was age-related. Brain MRI results showed that the distribution of cerebral cortex lesions was closely related to the classification of cortical encephalitis. Based on the patient's response to the treatment, glucocorticoid therapy was effective against MOG antibody-associated cortical encephalitis, which is consistent with the treatment response and clinical prognosis of MOGAD. Therefore, our opinion was that MOG antibody might be the "responsible antibody" in MOG antibody-associated cortical encephalitis, although further studies are needed to confirm this hypothesis.

Case report: A case of acute disseminated encephalomyelitis after SARS-CoV-2 infection in pediatric patients

Introduction

Since the beginning, there has been enough evidence about the multi-systematic involvement of the coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Recent observations have revealed that, together with others, typical neurological manifestations are also associated with COVID-19 infection. In the first 2 years, children accounted for a few percent of cases, but with the emergence of the Omicron variant, the number of cases in the pediatric population has increased. It has been described that ~5% of the affected population suffered from severe neurological complications, such as seizure, coma, encephalitis, demyelinating disorders, and aseptic meningitis. Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease of the central nervous system. Typically, it presents in childhood and occurs 1 or 2 weeks after infection or vaccination.

Case presentation

We present the case of a 12-year-old boy who developed ADEM, 10 days after an asymptomatic SARS-CoV-2 infection. Neurological symptoms began with headache, fever, irritability, paraplegia, and loss of sensitivity from the T1 level. The diagnosis of ADEM was confirmed by the typical signs found on brain MRI, whereas spinal cord MRI showed signs of transverse myelitis. The cerebrospinal fluid (CSF) testing excluded infections and did not reveal oligoclonal antibody bands (anti-MOG-negative and anti-AQP-negative). High-dose steroids (30 mg/kg/day) and IVIG (2 g/kg) were administered to the patient without any clinical improvement. The patient received a cycle of plasma exchange therapy, followed by rituximab infusion, with partial improvement. After 3 months, the magnetic resonance imaging (MRI) results demonstrated radiological improvement in accordance with the ADEM diagnosis.

Conclusion

This clinical case confirms that SARS-CoV-2 infections are increasingly implicated in severe neurological consequences in both adult and pediatric patients. While the most frequent complications that were reported in children included headache, altered mental status, and encephalopathy, ~5% of the individuals suffered from severe neurological complications, leading to lifelong sequelae. All physicians must be aware of these data and detect neurological signs of severe (or not) complications that require a specific follow-up and treatment.

Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease and an Incidental Thyroid Nodule

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare, immune-mediated demyelinating disease of the central nervous system (CNS) that has a predilection for children. Its association with malignancy or other autoimmune diseases is unclear. We present a case of MOGAD in a teenager with a coincidental thyroid malignancy and elevated intracranial pressure.