Effectiveness of immunotherapies in relapsing myelin oligodendrocyte glycoprotein antibody-associated disease

Clinical and imaging features and treatment response of anti-NMDAR encephalitis combined with MOGAD

BACKGROUND

To investigate the clinical, imaging features, immunotherapy of anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) combined with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

METHODS

A total of 124 patients with NMDARE and 86 patients with MOGAD were screened from an ongoing prospective cohort study (Clinical and Imaging Patterns of Neuroinflammation Diseases in China, CLUE). Ten NMDARE combined with MOGAD patients, were finally enrolled in this study. Clinical and imaging data and follow-up results characteristics were collected and analyzed.

RESULTS

In these 10 patients with NMDARE combined with MOGAD, 7 patients (70 %) showed recurrent courses. In all 26 episodes, 14 episodes (53.8 %) showed encephalitis-related symptoms, 6 episodes (23.1 %) showed demyelination-related symptoms, 6 episodes (23.1 %) showed both. The median CSF leukocytes were 13/μL (range 1-413) and the median protein was 0.43 g/L (range 0.22-0.70). MRI lesions were found involving the optic nerve (2/10), spinal cord (3/10), deep gray matter (3/10), cortex (6/10), subcortex (7/10), brainstem (5/10) and cerebellum (4/10). Leptomeningeal enhancement was found in 3 patients. All patients received high-dose intravenous methylprednisolone and immunoglobulin therapy during attacks. Seven patients received rituximab (RTX). The median annualized recurrence rate (ARR) reduced significantly following RTX treatments (z = -2.201, p = 0.028), and achieved good outcomes at the last follow-up visit (modified Rankin scale score ≤ 2).

CONCLUSION

NMDARE combined with MOGAD represents a unique characteristic of autoantibody-mediated encephalitis. Coexistence of NMDAR and MOG antibody may indicate high recurrence risk. RTX may be a relatively efficient therapeutic option.

Astragaloside II, a natural saponin, facilitates remyelination in demyelination neurological diseases via p75NTR receptor mediated β-catenin/Id2/MBP signaling axis in oligodendrocyte precursor cells

BACKGROUND

Demyelination is a hallmark of neurological disorders such as multiple sclerosis and neuromyelitis optica, leading to neurological deficits. Existing therapies primarily modulate immune responses but lack efficacy in directly promoting myelin repair. Enhancing oligodendrocyte precursor cell (OPC) differentiation and oligodendrocytes (OLs) production is crucial for restoring myelin integrity.

OBJECTIVES

This study investigated the therapeutic potential of astragaloside II (AS-II), a bioactive saponin with neuroprotective and pro-differentiation properties, derived from Astragalus membranaceus, uniquely in promoting OPC differentiation and myelin endogenous repair, distinguishing it from existing immunomodulatory treatments. AS-II directly targets p75 neurotrophin receptor (p75NTR) signaling, a pathway linked to myelin regeneration but underestimated in current remyelination strategies.

METHODS

We conducted in vitro OPC differentiation assays and in vivo demyelination models, including cuprizone and experimental autoimmune encephalomyelitis. Drug affinity responsive target stability mass spectrometry, cellular thermal shift assay, and surface plasmon resonance assays identified and validated p75NTR as the direct target of AS-II. p75NTR knockout mice and lentiviral transduction were used to confirm its role.

RESULTS

AS-II improved neurobehavioral outcomes, increased OLs production, and enhanced myelin integrity by suppressing β-catenin/Id2/MBP signaling. Mechanistically, AS-II bound to p75NTR (Pro253, Ser257), stabilizing its structure and promoting remyelination. In p75NTR knockout mice, AS-II failed to restore myelin or neural function, confirming its p75NTR-dependent mechanism.

CONCLUSION

AS-II represents a novel therapeutic candidate for demyelinating diseases, offering a targeted approach to myelin regeneration through direct p75NTR modulation and addressing gaps in current treatment strategies.

The utility of serum neurofilament light chain in MOGAD: Current insights and future directions

BACKGROUND

Serum neurofilament light chain (sNfL) has become an increasingly established biomarker for monitoring in multiple sclerosis (MS). Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a demyelinating disorder distinct from MS in terms of pathophysiology and treatment options, also presenting with demyelinating attacks that can result in permanent disability. Given its unpredictable disease course, the need for biomarkers reflective of the risk for poor clinical recovery or relapsing course is pressing. The purpose of this review is to summarize the current knowledge on sNfL levels in people with MOGAD, assess their utility for clinical practice and gain insights for future research.

METHODS

Embase, MEDLINE, Scopus, and CINAHL databases were searched following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Keywords used in the search included: (myelin oligodendrocyte glycoprotein OR MOG OR MOGAD) AND (neurofilament* OR neuro filament* OR NfL OR sNfL). This initial search generated 195 reports, 23 of which were original research articles investigating NfL levels in MOGAD patients, therefore meeting our inclusion criteria.

RESULTS

422 MOGAD patients were involved across all studies. Most studies revealed higher sNfL in MOGAD patients (n = 292) than in healthy controls (n = 3,172) with one study finding higher sNfL in MOGAD only during relapse. sNfL levels during attacks were similar when comparing MOGAD (n = 94) to MS (n = 256) and MOGAD (n = 149) to APQ4+ neuromyelitis optica spectrum disorder (APQ4+ NMOSD) (n = 214). MOGAD patients with brain lesions on magnetic resonance imaging (MRI) during a recent attack (n = 69 samples) had higher sNfL levels than patients without brain lesions (n = 78 samples). Median sNfL concentration was higher following clinical attacks (n = 69 samples) than in remission (n = 83 samples) in 3/5 studies. sNfL were higher at disease onset than subsequent attacks in 2 studies (n = 133 samples). Onset sNfL levels were not predictive of the likelihood of future relapse (relapsing: n = 15, monophasic: n = 18). A positive correlation was found between sNfL levels and attack severity assessed through various disability scales (n = 202), but not with the severity of acute or residual visual acuity (n = 45 eyes), or with residual retinal thickness among subjects with the optic neuritis (ON) phenotype (n = 11 eyes). The sGFAP/sNfL ratio showed utility in discriminating MOGAD from other autoimmune demyelinating diseases in two studies (MOGAD: n = 56, APQ4+ NMOSD: n = 66, MS: n = 31).

DISCUSSION

sNfL levels at presentation have limited utility in distinguishing MOGAD from other demyelinating disorders, but their combination with other biomarkers might improve their diagnostic utility. sNfL levels are higher in brain/spinal cord presentations than optic neuritis, correlating with clinical severity of these phenotypes but less so with the severity of visual outcome. Further studies should clarify the utility of sNfL as a biomarker for MOGAD, particularly in relation to long-term outcomes and imaging markers of central nervous system damage. Standardized sNfL testing parameters will improve study comparability and clinical application.

The atypical faces of optic neuritis: neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease

PURPOSE OF REVIEW

The purpose of this article is to provide a review of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), with a focus on what renders optic neuritis "atypical" in these two conditions. Clinical features, diagnostic criteria, and epidemiology are outlined. Acute treatments for optic neuritis, as well as immunotherapy for NMOSD and MOGAD are discussed.

RECENT FINDINGS

Updates in NMOSD and MOGAD are highlighted, with an emphasis on novel work including the new 2023 MOGAD diagnostic criteria, our evolving understanding on the epidemiology of these conditions, and recently FDA-approved NMOSD treatments. Pipeline therapies are also discussed.

SUMMARY

A thorough history and examination, supported by ancillary testing, continues to be the mainstay of optic neuritis diagnosis. Stratifying typical versus atypical optic neuritis is paramount. Within the atypical category, NMOSD and MOGAD are important considerations. Clues can point towards these diagnoses and guide steps for treatment, which is increasingly becoming targeted to individual diseases, as the pathophysiology is different for these disorders.

Neighborhood disadvantage, race, and clinical outcomes in neuromyelitis optica spectrum disorder

BACKGROUND

Little is known about the relationship between neighborhood disadvantage and neuromyelitis optica spectrum disorder (NMOSD) outcomes.

OBJECTIVE

The objective is to determine the impact of neighborhood disadvantage on time from symptom onset to diagnosis and annualized relapse rate (ARR).

METHODS

Neighborhood disadvantage were captured with the Area Deprivation Index (ADI), a validated measure of neighborhood-level disadvantage. Negative binomial regression models assessed the impact of ADI on diagnostic delay (⩾3 months between symptom onset and diagnosis) and ARR.

RESULTS

A total of 158 NMOSD patients were identified, a majority of whom were White (56.3%) and female (89.9%) with a mean age of 46 years at diagnosis. The ADI did not significantly affect odds of diagnostic delay (odds ratio (OR) = 0.99, p = 0.26). In univariable models, the ADI was not significantly associated with ARR (OR = 1.004, p = 0.29), but non-White race (OR = 1.541, p = 0.02) and time on immunosuppressive therapies (ISTs; OR = 0.994, p = 0.03) were. White patients used IST for an average of 81% of the follow-up period, compared to an average of 65% for non-White patients (p < 0.01).

CONCLUSION

No significant relationship between neighborhood-level disadvantage and diagnostic delay or ARR in NMOSD patients was observed. Non-White patients had a higher ARR, which may be related to less IST use.

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.

A Comparative Review of Typical and Atypical Optic Neuritis: Advancements in Treatments, Diagnostics, and Prognosis

Optic neuritis (ON) is a debilitating condition that through various mechanisms, including inflammation or demyelination of the optic nerve, can result in partial or total permanent vision loss if left untreated. Accurate diagnosis and promptly initiated treatment are imperative related to the potential of permanent loss of vision if left untreated, which can lead to a significant reduction in the quality of life in affected patients. ON is subtyped as "typical" or "atypical" based on underlying causative etiology. The etiology of ON can be differentiated when appropriate diagnostic testing is performed. Using history taking, neuroimaging, and visual testing to localize the underlying pathology of ON in a time-sensitive manner is critical in mitigating these unsatisfactory outcomes. Herein, we examine the differences in presentation, pathophysiology, and treatments of typical ON causes, like multiple sclerosis (MS), and atypical causes such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG) ON. The present investigation places focus on both neuroimaging and visual imaging in the differentiation of ON. Additionally, this review presents physicians with a better understanding of different presentations, treatments, and prognoses of ON.