GV-971 attenuates the progression of neuromyelitis optica in murine models and reverses alterations in gut microbiota and associated peripheral abnormalities.

AIMS: Growing evidence suggests that an imbalanced gut microbiota composition plays a crucial role in the development of neuromyelitis optica spectrum disorders (NMOSD), an inflammatory demyelinating disease primarily affecting the optic nerves and central nervous system (CNS). In light of this, we explored the potential therapeutic benefits of GV-971 in NMOSD. GV-971 is a drug used for treating mild-to-moderate Alzheimer's disease, which targets the gut-brain axis and reduces neuroinflammation. METHODS: To evaluate GV-971's effects, we employed the experimental autoimmune encephalomyelitis (EAE) mouse model to establish NMOSD animal models. This was achieved by injecting NMO-IgG into aged mice (11 months old) or using NMO-IgG along with complement injection and microbubble-enhanced low-frequency ultrasound (MELFUS) techniques in young mice (7 weeks old). We assessed the impact of GV-971 on incidence rate, clinical scores, body weight, and survival, with methylprednisolone serving as a positive control. In NMOSD models of young mice, we analyzed spinal cord samples through H&E staining, immunohistochemistry, and Luxol Fast Blue staining. Fecal samples collected at different time points underwent 16S rRNA gene sequencing, while plasma samples were analyzed using cytokine array and untargeted metabolomics analysis. RESULTS: Our findings indicated that GV-971 significantly reduced the incidence of NMOSD, alleviated symptoms, and prolonged survival in NMOSD mouse models. The NMOSD model exhibited substantial neuroinflammation and injury, accompanied by imbalances in gut microbiota, peripheral inflammation, and metabolic disorders, suggesting a potentially vicious cycle that accelerates disease pathogenesis. Notably, GV-971 effectively reduces neuroinflammation and injury, and restores gut microbiota composition, as well as ameliorates peripheral inflammation and metabolic disorders. CONCLUSIONS: GV-971 attenuates the progression of NMOSD in murine models and reduces neuroinflammation and injury, likely through its effects on remodeling gut microbiota and peripheral inflammation and metabolic disorders.

Neuromyelitis Optica spectrum disorder complicated with pure red cell aplasia: a case report.

BACKGROUND: Pure red cell aplasia (PRCA) in neuromyelitis optica spectrum disorder (NMOSD) has not been reported before. This study presents a patient with NMOSD who developed PRCA. CASE PRESENTATION: A 54-year-old female was admitted in January 2023 for dysuria and progressive numbness and weakness of lower limbs. She had difficulty standing and walking in a straight line. Both lower limbs were positive for the Babinski and Chaddock signs. MRI showed abnormal signals in the spinal cord. Aquaporin-4-IgG (AQP-4-IgG) was positive (1:320), and NMOSD was confirmed. Intravenous immunoglobulin and methylprednisolone were given, and the symptoms improved. She received maintenance treatment with methylprednisolone tablets, and the dosage was gradually reduced. She was readmitted for fatigue, palpitations, and shortness of breath in May 2023. Bone marrow aspiration and biopsy showed elevated erythroid precursors and erythroid hypoplasia, with normal megakaryocytes and myeloid precursors. Chest CT showed no mediastinal lymph node enlargement or thymoma. PRCA secondary to NMOSD was diagnosed. Recombinant human erythropoietin was given. Her condition improved after 1.5 months, as indicated by blood cell count and imaging. CONCLUSIONS: This case suggests that PRCA can be secondary to NMOSD. A comprehensive immune function and bone marrow evaluation might be necessary if abnormal blood cells are found while managing NMOSD.

Neuromyelitis in a Patient with Rheumatoid Arthritis: A Case Report.

A patient with longstanding rheumatoid arthritis (RA) complained of spinal cord symptoms after RA relapse. Contrast MRI demonstrated neuromyelitis in the upper thoracic spinal cord, and anti-aquaporin-4 (anti-AQP4) antibody was positive in the serum and cerebrospinal fluid (CSF). Neuromyelitis optica spectrum disorder (NMOSD) was diagnosed after excluding central nervous system (CNS) infection and tumor, and spinal cord symptoms were relieved after high dose of glucocorticoid and immunosuppressant were initiated for treatment.

Case report: Overlap syndrome of neuromyelitis optica spectrum disorder with anti-Argonaute antibodies.

Aquaporin-4 antibodies (AQP4-Abs) are a diagnostic marker for patients with a demyelinating disease called neuromyelitis optica spectrum disorder (NMOSD). Anti-Argonaute antibodies (AGO-Abs) present as potential biomarkers of the overlap syndrome between NMOSD and other autoimmune diseases. In this paper, we present the case of an adult woman with numbness, tingling, and burning sensations in her arms and subsequent bilateral internuclear ophthalmoplegia. Brain-cervical-thoracic magnetic resonance imaging (MRI) showed T2 hyperintensities in the dorsal brainstem and around the midbrain aqueduct and longitudinally transverse myelitis with homogeneous enhancement on gadolinium-enhanced MRI. The contemporaneous detection of AQP4- and AGO-Abs led to a definite diagnosis of overlap syndrome of NMOSD with AGO-Abs. The patient was treated with immunosuppressive agents, including corticosteroids and immunoglobulins, and achieved remission. This case highlights a novel phenotype of NMOSD with AGO-Abs overlap syndrome, which presents with relapsing brainstem syndrome and longitudinally extensive myelitis with acute severe neurological involvement. The promising prognosis of the disease could serve as a distinct clinical profile. Broad screening for antibodies against central nervous system autoimmune antigens is recommended in suspected patients with limited or atypical clinical manifestations.

Treatment strategies and responses for attacks of neuromyelitis optica spectrum disorder: A real-world retrospective cohort study.

We aimed to assess the treatment strategies utilized in patients with neuromyelitis optica spectrum disorder (NMOSD) experiencing relapses, including their frequency, types, and response after 6 months based on the Expanded Disability Status Scale (EDSS) score. METHODS: We conducted a retrospective study involving NMOSD patients from the Argentinean MS and NMOSD registry (RelevarEM, NCT03375177). Treatment response at 6 months was categorized as "good" if the EDSS score decreased by ≥1 point after a nadir EDSS score ≤ 3, or by ≥2 points after a nadir EDSS score > 3, "poor" if the EDSS score decrease was slighter, and as "absent" if the EDSS score remained unchanged or worsened. RESULTS: We included 120 NMOSD patients (seropositive N = 75), who experienced 250 NMOSD-related relapses and received 248 treatments. At 6 months, complete recovery was achieved in 70/98 (71.4%) and 15/19 (79%) patients, respectively. Predictors of a "good" response in our regression model were a younger age at disease onset (OR:3.54, CI95% 2.45-5.01, p < 0.0001) and a short delay from onset of relapse to treatment initiation (OR:1.56, CI95% 1.22-2.13, p = 0.004). CONCLUSIONS: Approximately two-thirds of patients experienced complete recovery, and younger age and a short delay to start treatment were independent predictors of a "good" response.

Interleukin-6 Signaling Blockade Induces Regulatory Plasmablasts in Neuromyelitis Optica Spectrum Disorder.

BACKGROUND AND OBJECTIVES: Interleukin-6 receptor antibodies (IL-6R Abs), including satralizumab, are increasingly used to prevent relapse for neuromyelitis optica spectrum disorder (NMOSD). However, the detailed mechanism of action of this treatment on the lymphocyte phenotype remains unclear. This study focused on B cells in patients with NMOSD, hypothesizing that IL-6R Ab enables B cells to acquire regulatory functions by producing the anti-inflammatory cytokine IL-10. METHODS: Peripheral blood mononuclear cells were stimulated in vitro to induce the expansion of B-cell subsets, double-negative B cells (DNs; CD19+ IgD-, CD27-) and plasmablasts (PBs; CD19+, CD27hi, CD38hi). Whole B cells, DNs, or PBs were isolated after culture with IL-6R Ab, and IL-10 expression was quantified using quantitative PCR and a cytometric bead array. RNA sequencing was performed to identify the marker of regulatory PBs induced by IL-6R Ab. RESULTS: DNs and PBs were observed to expand in patients with NMSOD during the acute attacks. In the in vitro model, IL-6R Ab increased IL-10 expression in B cells. Notably, IL-10 expression increased in PBs but not in DNs. Using RNA sequencing, CD200 was identified as a marker of regulatory PBs among the differentially expressed upregulated genes. CD200+ PBs produced more IL-10 than CD200- PBs. Furthermore, patients with NMOSD who received satralizumab had a higher proportion of CD200+ PBs than patients during the acute attacks. DISCUSSION: Treatment with IL-6 signaling blockade elicited a regulatory phenotype in B cells and PBs. CD200+ PBs may be a marker of treatment responsiveness in the context of NMOSD pathophysiology.

Preferences for neuromyelitis optica spectrum disorder treatments: A conjoint analysis with neurologists in Spain.

BACKGROUND: The treatment landscape for neuromyelitis optica spectrum disorder (NMOSD) has changed in recent years with the approval of therapies with different efficacy, safety and administration profiles. OBJECTIVE: The aim of this study was to assess neurologists' preferences for different NMOSD treatment attributes using conjoint analysis (CA). METHODS: We conducted an online, non-interventional, cross-sectional study in collaboration with the Spanish Society of Neurology. Our CA assessed five drugs' attributes: prevention of relapse, prevention of disability accumulation, safety risk, management during pregnancy, and route and frequency of administration. Participants were presented with eight hypothetical treatment scenarios to rank based on their preferences from the most preferred to the least. An ordinary least squares method was selected to estimate weighted preferences. RESULTS: A total of 104 neurologists were included. Mean age (standard deviation-SD) was 37.7 (10.3) years, 52.9 % were male, and median time (interquartile range) of experience managing NMOSD was 5.0 (2.9, 10.8) years. Neurologists placed the greatest importance on efficacy attributes, time to relapse (44.1 %) being the most important, followed by preventing disability accumulation (36.8 %). In contrast, route and frequency of administration (4.6 %) was the least important characteristic. Participants who prioritised efficacy attributes felt more comfortable in decision-making, had fewer past experiences of care-related regret and a lower attitude to risk taking than their counterparts. CONCLUSION: Neurologists' treatment preferences in NMOSD were mainly driven by efficacy attributes. These results may be useful to design policy decisions and treatment guidelines for this condition.

Mechanisms of gastrointestinal toxicity in neuromyelitis optica spectrum disorder patients treated with mycophenolate mofetil: insights from a mouse model and human study.

Mycophenolate mofetil (MMF) is commonly utilized for the treatment of neuromyelitis optica spectrum disorders (NMOSD). However, a subset of patients experience significant gastrointestinal (GI) adverse effects following MMF administration. The present study aims to elucidate the underlying mechanisms of MMF-induced GI toxicity in NMOSD. Utilizing a vancomycin-treated mouse model, we compiled a comprehensive data set to investigate the microbiome and metabolome in the GI tract to elucidate the mechanisms of MMF GI toxicity. Furthermore, we enrolled 17 female NMOSD patients receiving MMF, who were stratified into non-diarrhea NMOSD and diarrhea NMOSD (DNM) groups, in addition to 12 healthy controls. The gut microbiota of stool samples was analyzed using 16S rRNA gene sequencing. Vancomycin administration prevented weight loss and tissue injury caused by MMF, affecting colon metabolomes and microbiomes. Bacterial ß-glucuronidase from Bacteroidetes and Firmicutes was linked to intestinal tissue damage. The DNM group showed higher alpha diversity and increased levels of Firmicutes and Proteobacteria. The ß-glucuronidase produced by Firmicutes may be important in causing gastrointestinal side effects from MMF in NMOSD treatment, providing useful information for future research on MMF. IMPORTANCE: Neuromyelitis optica spectrum disorder (NMOSD) patients frequently endure severe consequences like paralysis and blindness. Mycophenolate mofetil (MMF) effectively addresses these issues, but its usage is hindered by gastrointestinal (GI) complications. Through uncovering the intricate interplay among MMF, gut microbiota, and metabolic pathways, this study identifies specific gut bacteria responsible for metabolizing MMF into a potentially harmful form, thus contributing to GI side effects. These findings not only deepen our comprehension of MMF toxicity but also propose potential strategies, such as inhibiting these bacteria, to mitigate these adverse effects. This insight holds broader implications for minimizing complications in NMOSD patients undergoing MMF therapy.

Safety and efficacy of inebilizumab for the treatment of neuromyelitis optica spectrum disorder: end-of-study results from the open-label period of the N-MOmentum trial.

BACKGROUND: Inebilizumab, an anti-CD19 B-cell-depleting antibody, demonstrated safety and efficacy in neuromyelitis optica spectrum disorder in the randomised controlled period of the N-MOmentum trial. Here, end-of-study data, including the randomised controlled period and open-label extension period, are reported. METHODS: In the double-blind, randomised, placebo-controlled, phase 2/3 N-MOmentum trial, adults aged 18 years and older with an neuromyelitis optica spectrum disorder diagnosis, Expanded Disability Status Scale score of 8·0 or less, and history of either at least one acute inflammatory attack requiring rescue therapy in the past year or two attacks requiring rescue therapy in the past 2 years, were recruited from 81 outpatient specialty clinics or hospitals in 24 countries. Eligible participants were randomly assigned (3:1), using a central interactive voice system or interactive web response system, and a permuted block randomisation scheme (block size of 4), to receive intravenous inebilizumab (300 mg) or identical placebo on days 1 and 15 of the randomised period, which lasted up to 197 days. Participants and all study staff were masked to treatment assignment. The primary endpoint of the randomised period of the trial was time to onset of adjudicated neuromyelitis optica spectrum disorder attack on or before day 197. Participants in the randomised controlled period who had an adjudicated attack, completed 197 days in the study, or were in the randomised controlled period when enrolment stopped, could voluntarily enter the open-label period. In the open-label period, participants either initiated inebilizumab if assigned placebo (receiving 300 mg on days 1 and 15 of the open-label period) or continued treatment if assigned inebilizumab (receiving 300 mg on day 1 and placebo on day 15, to maintain B-cell depletion and masking of the randomised controlled period). All participants subsequently received inebilizumab 300 mg every 6 months for a minimum of 2 years. The end-of-study analysis endpoints were time to adjudicated attack and annualised attack rate (assessed in all participants who received inebilizumab at any point during the randomised controlled period or open-label period [any inebilizumab population] and the aquaporin-4 [AQP4]-IgG seropositive subgroup [any inebilizumab-AQP4-IgG seropositive population]) and safety outcomes (in all participants who were exposed to inebilizumab, analysed as-treated). This study is registered with ClinicalTrials.gov, NCT02200770, and is now complete. FINDINGS: Between Jan 6, 2015, and Sept 24, 2018, 467 individuals were screened, 231 were randomly assigned, and 230 received at least one dose of inebilizumab (n=174) or placebo (n=56). Between May 19, 2015, and Nov 8, 2018, 165 (95%) of 174 participants in the inebilizumab group and 51 (91%) of 56 in the placebo group entered the open-label period (mean age 42·9 years [SD 12·4], 197 [91%] of 216 were female, 19 [9%] were male, 115 [53%] were White, 45 [21%] were Asian, 19 [9%] were American Indian or Alaskan Native, and 19 [9%] were Black or African American). As of data cutoff for this end of study analysis (Dec 18, 2020; median exposure 1178 days [IQR 856-1538], total exposure of 730 person-years) 225 participants formed the any inebilizumab population, and 208 (92%) participants were AQP4-IgG seropositive. Overall, 63 adjudicated neuromyelitis optica spectrum disorder attacks occurred in 47 (21%) of 225 treated participants (60 attacks occurred in 44 [21%] of 208 in the AQP4-IgG seropositive subgroup); 40 (63%) of 63 attacks occurred in 34 (15%) of 225 treated participants during the first year of treatment. Of individuals who had an adjudicated attack while receiving inebilizumab, 36 (77%) of 47 were subsequently attack-free at the end of 4 years. Annualised attack rates decreased year-on-year, with end-of-study adjusted annualised attack rates being similar in the any inebilizumab-AQP4-IgG seropositive subgroup (0·097 [95% CI 0·070-0·14]) and any inebilizumab populations (0·092 [0·067-0·13]). Overall, 208 (92%) of 225 participants who received any inebilizumab had at least one treatment-emergent adverse event, the most frequent of which were urinary tract infection (59 [26%]), nasopharyngitis (47 [21%]), and arthralgia (39 [17%]). Infection rates did not increase over 4 years. Three (1%) of 225 participants in the any inebilizumab population died during the open-label period (one each due to a CNS event of unknown cause and pneumonia, respiratory insufficiency resulting from an neuromyelitis optica spectrum disorder attack and viral pneumonia related to COVID-19), all of which were deemed to be unrelated to treatment. INTERPRETATION: Data from the end-of-study analysis of the N-MOmentum trial showed continued and sustained clinical benefits of long-term inebilizumab treatment in individuals with neuromyelitis optica spectrum disorder, which supports the role of inebilizumab as a CD19+ B-cell-depleting therapy in neuromyelitis optica spectrum disorder. FUNDING: MedImmune and Viela Bio/Horizon Therapeutics, now part of Amgen.

Moving towards a new era for the treatment of neuromyelitis optica spectrum disorders.

Neuromyelitis optica spectrum disorders (NMOSD) include a rare group of autoimmune conditions that primarily affect the central nervous system. They are characterized by inflammation and damage to the optic nerves, brain and spinal cord, leading to severe vision impairment, locomotor disability and sphynteric disturbances. In the majority of cases, NMOSD arises due to specific serum immunoglobulin G (IgG) autoantibodies targeting aquaporin 4 (AQP4-IgG), which is the most prevalent water-channel protein of the central nervous system. Early diagnosis and treatment are crucial to manage symptoms and prevent long-term disability in NMOSD patients. NMOSD were previously associated with a poor prognosis. However, recently, a number of randomized controlled trials have demonstrated that biological therapies acting on key elements of NMOSD pathogenesis, such as B cells, interleukin-6 (IL-6) pathway, and complement, have impressive efficacy in preventing the occurrence of clinical relapses. The approval of the initial drugs marks a revolutionary advancement in the treatment of NMOSD patients, significantly transforming therapeutic options and positively impacting their prognosis. In this review, we will provide an updated overview of the key immunopathological, clinical, laboratory, and neuroimaging aspects of NMOSD. Additionally, we will critically examine the latest advancements in NMOSD treatment approaches. Lastly, we will discuss key aspects regarding optimization of treatment strategies and their monitoring.

4-Octyl itaconate inhibits inflammation via the NLRP3 pathway in neuromyelitis optica spectrum disorders.

OBJECTIVE: Neuromyelitis optica spectrum disorders (NMOSD) are rare inflammatory astrocytic diseases of the central nervous system (CNS). The roles of immune response gene-1 (IRG1) and the IRG1-itaconic acid-NLRP3 inflammatory pathway in the pathogenesis of NMOSD and the effects of 4-octyl itaconate (4-OI) on the NLRP3 inflammatory pathway in NMOSD are unclear. This study aimed to determine the role of IRG1 and the activation status of the NLRP3 inflammatory pathway in acute-onset NMOSD and to investigate the inhibitory effects of 4-OI on NLRP3 inflammasome activation via the IRG1-itaconic acid-NLRP3 pathway in monocytes and macrophages by using in vitro models. METHODS: Peripheral blood mononuclear cells (PBMCs) and serum were collected from patients with acute NMOSDs and healthy controls (HC), followed by monocyte typing and detection of the expression of NLRP3-related inflammatory factors. Subsequently, the effects of 4-OI on the IRG1-itaconic acid-NLRP3 pathway were investigated in peripheral monocytes from patients with NMOSD and in macrophages induced by human myeloid leukemia mononuclear cells (THP-1 cells) via in vitro experiments. RESULTS: Patients with acute NMOSD exhibited upregulated IRG1 expression. In particular, the upregulation of the expression of the NLRP3 inflammasome and proinflammatory factors was notable in monocytes in acute NMOSD patients. 4-OI inhibited the activation of the IRG1-itaconic acid-NLRP3 inflammatory pathway in the PBMCs of patients with NMOSD. INTERPRETATION: 4-OI could effectively inhibit NLRP3 signaling, leading to the inhibition of proinflammatory cytokine production in patients with NMOSD-derived PBMCs and in a human macrophage model. Thus, 4-OI and itaconate could have important therapeutic value for the treatment of NMOSD in the future.

FCGR3A-V158F gene polymorphism: A potential predictor for rituximab dosing optimization in Chinese patients with neuromyelitis optica spectrum disorder.

BACKGROUND: Rituximab (RTX), an anti-CD20 monoclonal antibody, has shown promise in managing neuromyelitis optica spectrum disorders (NMOSD) by depleting B cells and reducing relapses. However, there is no consensus on the optimal RTX dosing regimen, and genetic factors, such as FCGR3A-V158F polymorphism, may influence treatment outcomes. This study investigates how FCGR3A-V158F genotypes influence RTX efficacy in Chinese NMOSD patients under varying dosing regimens and aims to optimize treatment protocols. METHODS: We conducted a retrospective analysis of 25 Chinese NMOSD patients treated with RTX, grouped into standardized and low-dosage regimens. FCGR3A-V158F genotypes were determined, and treatment responses were evaluated, including relapse rates, time to first relapse (TFR), B-cell depletion, dose adjustments, and treatment retention. RESULTS: Among all patients, 15 received standardized dosages, while 10 received varied induction doses (500 mg to 1200 mg) in low-dose regimens. For FCGR3A-V158F genotypes, 15 had the FF genotype, and 10 were V carriers (3 VV genotype, 7 VF genotype). Regardless of dosing, FF genotype patients had a higher relapse rate post-RTX treatment compared to V carriers (P < 0.05). None of the 3 VV genotype patients in either dose group experienced relapses post-RTX. In both dose groups, FF genotype patients had significantly shorter TFR and required more RTX dose adjustments post-RTX treatment compared to V carriers in the standardized dosage group (P < 0.05). FF genotype patients in the low dosage group were more likely to experience insufficient B-cell depletion, had lower treatment retention rates, and more discontinuations than V carriers in the standardized dosage group (P < 0.05). Insufficient B-cell depletion significantly predicted clinical relapses after RTX treatment (P < 0.05). In survival analysis, FF genotype patients, regardless of dosing, experienced earlier relapses post-RTX treatment (P < 0.05). CONCLUSIONS: This study highlights the importance of RTX dosage selection in NMOSD treatment, particularly for FCGR3A-FF genotype patients. Standard-dose RTX therapy with vigilant monitoring of peripheral blood B-cell levels is recommended for these individuals to optimize treatment efficacy.

Rituximab-induced gut microbiota changes in Chinese neuromyelitis optica spectrum disorders.

BACKGROUND: Recent evidence shows that immunosuppressive agents can affect the gut microbiota in autoimmune diseases. However, the relationship between the gut microbiome and B-cell depletion immunotherapy in neuromyelitis optica spectrum disorder (NMOSD) remains poorly understood. OBJECTIVES: To evaluate the distinct intestinal microbial patterns and serum cytokine levels after short-term rituximab treatment (three months) in patients with NMOSD. METHODS: Firstly, we conducted a cross-sectional study involving 46 treatment-naïve NMOSD patients and 48 matched healthy controls. We collected fecal specimens, which were then analyzed using next-generation sequencing, and quantified serum cytokines. Subsequently, fecal and serum samples were re-collected and re-evaluated in 31 of the 46 treatment-naïve NMOSD patients after RTX treatment. RESULTS: Comparing the gut microbiome of treatment-naïve NMOSD patients to that of healthy controls revealed low α-diversity and distinct microbial compositions in the former. The microbial composition in NMOSD patients underwent changes following three months of RTX treatment. Specifically, the levels of IL-17F and IL-6 decreased, while those of IL-10 and TNFα increased after RTX treatment. LEfSe analysis identified 27 KEGG categories with significantly differential abundances between NMOSD patients and RTX treatment group. CONCLUSIONS: Our study provides a comprehensive understanding of the gut microbiota landscape in the context of B-cell depletion immunotherapy. We observed dysbiosis in the gut microbiome of NMOSD patients, which was partially alleviated by three months of RTX treatment. This suggests that B-cell depletion may play a crucial role in driving changes in the gastrointestinal environment.

Lycium barbarum glycopeptide ameliorates motor and visual deficits in autoimmune inflammatory diseases.

BACKGROUND: Lycium barbarum glycopeptide (LbGp), extracted from the traditional Chinese medicine (TCM) of Lycium barbarum (LB), provides a neuroprotective effect against neurodegenerative and neuroimmune disorders contributing to its immunomodulatory and anti-inflammatory roles. Neuromyelitis optica spectrum disorders (NMOSD) is an autoimmune-mediated central nervous system (CNS) demyelinating disease, clinically manifested as transverse myelitis (TM) and optic neuritis. However, no drug has been demonstrated to be effective in relieving limb weakness and visual impairment of NMOSD patients. PURPOSE: This study investigates the potential role of LbGp in ameliorating pathologic lesions and improving neurological dysfunction during NMOSD progression, and to elucidate the underlying mechanisms for the first time. STUDY DESIGN: We administrate LbGp in experimental NMOSD models in ex vivo and in vivo to explore its effect on NMOSD. METHODS: To evaluate motor function, both rotarod and gait tasks were performed in systemic NMOSD mice models. Furthermore, we assessed the severity of NMO-like lesions of astrocytes, organotypic cerebellar slices, as well as brain, spinal cord and optic nerve sections from NMOSD mouse models with LbGp treatment by immunofluorescent staining. In addition, demyelination levels in optic nerve were measured by G-ratio through Electro-microscopy (EM). And inflammation response was explored through detecting the protein levels of proinflammatory cytokines and NF-κB signaling in astrocytic culture medium and spinal cord homogenates respectively by Elisa and by Western blotting. RESULTS: LbGp could significantly reduce astrocytes injury, demyelination, and microglial activation in NMOSD models. In addition, LbGp also improved locomotor and visual dysfunction through preventing neuron and retinal ganglion cells (RGCs) from inflammatory attack in a systemic mouse model. Mechanistically, LbGp inhibits proinflammatory factors release via inhibition of NF-κB signaling in NMOSD models. CONCLUSION: This study provides evidence to develop LbGp as a functional TCM for the clinical treatment of NMOSD.

Machine Learning Analysis Using RNA Sequencing to Distinguish Neuromyelitis Optica from Multiple Sclerosis and Identify Therapeutic Candidates.

This study aims to identify RNA biomarkers distinguishing neuromyelitis optica (NMO) from relapsing-remitting multiple sclerosis (RRMS) and explore potential therapeutic applications leveraging machine learning (ML). An ensemble approach was developed using differential gene expression analysis and competitive ML methods, interrogating total RNA-sequencing data sets from peripheral whole blood of treatment-naïve patients with RRMS and NMO and healthy individuals. Pathway analysis of candidate biomarkers informed the biological context of disease, transcription factor activity, and small-molecule therapeutic potential. ML models differentiated between patients with NMO and RRMS, with the performance of certain models exceeding 90% accuracy. RNA biomarkers driving model performance were associated with ribosomal dysfunction and viral infection. Regulatory networks of kinases and transcription factors identified biological associations and identified potential therapeutic targets. Small-molecule candidates capable of reversing perturbed gene expression were uncovered. Mitoxantrone and vorinostat-two identified small molecules with previously reported use in patients with NMO and experimental autoimmune encephalomyelitis-reinforced discovered expression signatures and highlighted the potential to identify new therapeutic candidates. Putative RNA biomarkers were identified that accurately distinguish NMO from RRMS and healthy individuals. The application of multivariate approaches in analysis of RNA-sequencing data further enhances the discovery of unique RNA biomarkers, accelerating the development of new methods for disease detection, monitoring, and therapeutics. Integrating biological understanding further enhances detection of disease-specific signatures and possible therapeutic targets.

Impact of rituximab treatment regime on time to relapse in aquaporin-4 antibody positive neuromyelitis optica spectrum disorder.

BACKGROUND: Aquaporin-4 (AQP4) antibody associated neuromyelitis optica (NMOSD) requires long-term immunosuppression. Rituximab is increasingly used worldwide, however the optimal regime is not established. METHODS: We retrospectively examined different rituximab regimens in AQP4-NMOSD. Standard monotherapy (SM; 6 monthly infusions), SM plus oral steroids (SM+S), extended interval dosing (EID; guided by CD19 repopulation) and EID with oral steroids (EID+S) were compared. The primary outcome was time to first clinical relapse. Potential confounders including age, gender, number of previous relapses, and onset phenotype were included. RESULTS: 77 patients were included: 67 females, median onset age 35.6, median DSS at rituximab initiation 5.0. 39 were on SM+S, 20 SM, 6 EID, and 12 EID+S. 25/77 patients relapsed during a median follow-up of 44.0 months. No significant difference in time to first relapse was observed between any rituximab regimen. Pooled analyses to compare regimens that use standard monotherapy (SM and SM+S) against those that use extended interval dosing (EID and EID+S) showed no significant difference. Pooled analysis of regimens using steroids with those not using steroids also showed no significant difference. Adjusted Cox proportional hazard model revealed no significant difference between rituximab regimens or influence of demographic factors. 9 significant adverse events were recorded, 5 in the SM group and 4 in SM+S. CONCLUSIONS: This study provides some basis for further exploring EID as a viable option for long term treatment of AQP4-NMOSD. This may improve patient experience and consolidate use of hospital resources.

Effectiveness of tixagevimab/cilgavimab (Evusheld) in antiCD20­treated patients with multiple sclerosis and neuromyelitis optica spectrum disorder.

BACKGROUND: AntiCD20 therapy, such as rituximab, ocrelizumab, or ofatumumab, effectively treats patients with multiple sclerosis (pwMS) or neuromyelitis optica spectrum disorder (pwNMOSD) but negatively affects the humoral immune response to COVID-19 vaccination. One strategy to protect these patients is using tixagevimab/cilgavimab (T/C) as pre-exposure prophylaxis. This study aimed to evaluate the effect of T/C on the incidence of COVID-19 in pwMS and pwNMOSD. METHODS: Data in this observational cohort study were collected in two Czech MS centres through ReMuS registry between March 1, 2020 and December 31, 2022. Adult pwMS and pwNMOSD who were (1) treated with antiCD20 therapy at least six months before T/C administration, or at least from February 1, 2022 in the control group; (2) were already on antiCD20 therapy at the time of vaccination or COVID-19 infection; and (3) were on antiCD20 therapy at least 100 days after T/C, or at least 90 days after August 1, 2022 in the control group, were included. Analysis was performed using frequency-based (propensity score matching) and Bayesian statistical methods (informative and non-informative priors). RESULTS: Using propensity score matching 1:1, 47 patients who received T/C (mean age 45.7 years, median disease duration 12.5 years) were matched with those who did not receive T/C (n = 341; mean age 46.6 years, median disease duration 11.4 years) based on age, MS/NMOSD duration, and number of vaccine doses. None of the T/C patients and three in the control matched group, developed COVID-19 between 10 and 100 days after receiving T/C, August 1, 2022, respectively. The frequency of COVID-19 was not significantly different between groups (p = 0.242). Due to the low number of patients, a Bayesian analysis was also added. Using a non-informative Bayesian prior, the median relative risk of COVID-19 after T/C was 7.6 % (95 % CrI 0.02-115.9 %). The posterior probability of risk difference lower than zero was 96.4 %. Using an informative prior (based on the registration study of Evusheld), the median relative risk of COVID-19 after T/C was 20.2 % (95 % CI 8.4-43.8 %). The posterior probability of the risk difference lower than zero was 100 %. CONCLUSION: This work highlights the possible good efficacy of T/C in antiCD20-treated pwMS and pwNMSOD. Based on Bayesian analysis with an informative prior, the T/C group's risk of COVID-19 infection was approximately 20.2 % of the control group's risk. However, given the low frequency of COVID-19, the results of this pilot analysis must be interpreted with caution.

Role of C5 inhibitors in neuromyelitis optica spectrum disorders with seropositive anti-aquaporin-4 antibody: A systematic review and meta-analysis.

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder characterized by relapses of inflammation and demyelination primarily affecting the optic nerve and the spinal cord. C5 complement inhibition is an effective therapeutic approach in the treatment of NMOSD. In this systematic review and meta-analysis, we aimed to determine the role of C5 inhibitors in the treatment of patients with seropositive anti-aquaporin-4 antibody (AQP4+IgG) NMOSD. METHODS: This systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Relevant articles were systematically searched through Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases until October 6th, 2023. We included randomized clinical trials (RCTs) that investigated the treatment with C5 inhibitors compared to placebo in patients with seropositive NMOSD. The primary endpoint was the rates of first adjudicated relapse. Secondary endpoints included different disability and quality of life measures. The random-effects model was used for all statistical analyses. RESULTS: Two RCTs with a total of 201 patients were included. C5 inhibitors demonstrated significant reduction of first adjudicated relapse (risk ratio (RR) = 0.05, 95 % CI 0.01-0.15) and Hauser Ambulation Index (HAI) (mean difference (MD): -0.79, 95 % CI -1.27 to -0.31). There was no significant difference between the two groups in Expanded Disability Status Scale (EDSS) (MD -0.23, 95 % CI -0.54-0.08). C5 inhibitors significantly improved the mean change in EQ-5D index (MD 0.08, 95 % CI 0.01-0.14; P = 0.02); however, no significant difference was shown in the mean change in EQ-5D VAS (MD 3.79, 95 % CI -1.61 to 9.19; P = 0.17). Safety measures were comparable between C5 inhibitors and placebo. CONCLUSION: NMOSD Patients with AQP4+IgG receiving C5 inhibitors have lower rate of relapses and improved levels of disability and quality of life. Real-world studies are warranted to establish the long-term safety of C5 inhibitors.