COVID-19 outcomes in patients with multiple sclerosis: Understanding changes from 2020 to 2022.

BACKGROUND: Epidemiologic studies on coronavirus disease 2019 (COVID-19) in patients with multiple sclerosis (pwMS) have focused on the first waves of the pandemic until early 2021. OBJECTIVES: We aimed to extend these data from the onset of the pandemic to the global coverage by vaccination in summer 2022. METHODS: This retrospective, multicenter observational study analyzed COVISEP registry data on reported COVID-19 cases in pwMS between January 2020 and July 2022. Severe COVID-19 was defined as hospitalization or higher severity. RESULTS: Among 2584 pwMS with confirmed/highly suspected COVID-19, severe infection rates declined from 14.6% preomicron wave to 5.7% during omicron wave (p < 0.001). Multivariate analysis identified age (odds ratio (OR) = 1.43, 95% confidence interval (CI) = [1.25-1.64] per 10 years), male sex (OR = 2.01, 95% CI = [1.51-2.67]), obesity (OR = 2.36, 95% CI = [1.52-3.68]), cardiac comorbidities (OR = 2.36, 95% CI = [1.46-3.83]), higher Expanded Disability Status Scale (EDSS) scores (OR = 2.09, 95% CI = [1.43-3.06] for EDSS 3-5.5 and OR = 4.53, 95% CI = [3.04-6.75] for EDSS ⩾6), and anti-CD20 therapies (OR = 2.67, 95% CI = [1.85-3.87]) as risk factors for COVID-19 severity. Vaccinated individuals experienced less severe COVID-19, whether on (risk ratio (RR) = 0.64, 95% CI = [0.60-0.69]) or off (RR = 0.32, 95% CI = [0.30-0.33]) anti-CD20. DISCUSSION: In pwMS, consistent risk factors were anti-CD20 therapies and neurological disability, emerging as vital drivers of COVID-19 severity regardless of wave, period, or vaccination status.

Scoping review of clinical decision support systems for multiple sclerosis management: Leveraging information technology and massive health data.

BACKGROUND AND PURPOSE: Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system, with numerous therapeutic options, but a lack of biomarkers to support a mechanistic approach to precision medicine. A computational approach to precision medicine could proceed from clinical decision support systems (CDSSs). They are digital tools aiming to empower physicians through the clinical applications of information technology and massive data. However, the process of their clinical development is still maturing; we aimed to review it in the field of MS. METHODS: For this scoping review, we screened systematically the PubMed database. We identified 24 articles reporting 14 CDSS projects and compared their technical and software development aspects. RESULTS: The projects position themselves in various contexts of usage with various algorithmic approaches: expert systems, CDSSs based on similar patients' data visualization, and model-based CDSSs implementing mathematical predictive models. So far, no project has completed its clinical development up to certification for clinical use with global release. Some CDSSs have been replaced at subsequent project iterations. The most advanced projects did not necessarily report every step of clinical development in a dedicated article (proof of concept, offline validation, refined prototype, live clinical evaluation, comparative prospective evaluation). They seek different software distribution options to integrate into health care: internal usage, "peer-to-peer," and marketing distribution. CONCLUSIONS: This review illustrates the potential of clinical applications of information technology and massive data to support MS management and helps clarify the roadmap for future projects as a multidisciplinary and multistep process.

The radiologically isolated syndrome: revised diagnostic criteria.

The radiologically isolated syndrome (RIS) was defined in 2009 as the presence of asymptomatic, incidentally identified demyelinating-appearing white matter lesions in the CNS within individuals lacking symptoms typical of multiple sclerosis (MS). The RIS criteria have been validated and predict the transition to symptomatic MS reliably. The performance of RIS criteria that require fewer MRI lesions is unknown. 2009-RIS subjects, by definition, fulfil three to four of four criteria for 2005 dissemination in space (DIS) and subjects fulfilling only one or two lesions in at least one 2017 DIS location were identified within 37 prospective databases. Univariate and multivariate Cox regression models were used to identify predictors of a first clinical event. Performances of different groups were calculated. Seven hundred and forty-seven subjects (72.2% female, mean age 37.7 ± 12.3 years at the index MRI) were included. The mean clinical follow-up time was 46.8 ± 45.4 months. All subjects had focal T2 hyperintensities suggestive of inflammatory demyelination on MRI; 251 (33.6%) fulfilled one or two 2017 DIS criteria (designated as Groups 1 and 2, respectively), and 496 (66.4%) fulfilled three or four 2005 DIS criteria representing 2009-RIS subjects. Group 1 and 2 subjects were younger than the 2009-RIS group and were more likely to develop new T2 lesions over time (P < 0.001). Groups 1 and 2 were similar regarding survival distribution and risk factors for transition to MS. At 5 years, the cumulative probability for a clinical event was 29.0% for Groups 1 and 2 compared to 38.7% for 2009-RIS (P = 0.0241). The presence of spinal cord lesions on the index scan and CSF-restricted oligoclonal bands in Groups 1-2 increased the risk of symptomatic MS evolution at 5 years to 38%, comparable to the risk of development in the 2009-RIS group. The presence of new T2 or gadolinium-enhancing lesions on follow-up scans independently increased the risk of presenting with a clinical event (P < 0.001). The 2009-RIS subjects or Groups 1 and 2 with at least two of the risk factors for a clinical event demonstrated better sensitivity (86.0%), negative predictive value (73.1%), accuracy (59.8%) and area under the curve (60.7%) compared to other criteria studied. This large prospective cohort brings Class I evidence that subjects with fewer lesions than required in the 2009 RIS criteria evolve directly to a first clinical event at a similar rate when additional risk factors are present. Our results provide a rationale for revisions to existing RIS diagnostic criteria.

Microglial control of astrocytes in response to microbial metabolites.

Microglia and astrocytes modulate inflammation and neurodegeneration in the central nervous system (CNS)1-3. Microglia modulate pro-inflammatory and neurotoxic activities in astrocytes, but the mechanisms involved are not completely understood4,5. Here we report that TGFα and VEGF-B produced by microglia regulate the pathogenic activities of astrocytes in the experimental autoimmune encephalomyelitis (EAE) mouse model of multiple sclerosis. Microglia-derived TGFα acts via the ErbB1 receptor in astrocytes to limit their pathogenic activities and EAE development. Conversely, microglial VEGF-B triggers FLT-1 signalling in astrocytes and worsens EAE. VEGF-B and TGFα also participate in the microglial control of human astrocytes. Furthermore, expression of TGFα and VEGF-B in CD14+ cells correlates with the multiple sclerosis lesion stage. Finally, metabolites of dietary tryptophan produced by the commensal flora control microglial activation and TGFα and VEGF-B production, modulating the transcriptional program of astrocytes and CNS inflammation through a mechanism mediated by the aryl hydrocarbon receptor. In summary, we identified positive and negative regulators that mediate the microglial control of astrocytes. Moreover, these findings define a pathway through which microbial metabolites limit pathogenic activities of microglia and astrocytes, and suppress CNS inflammation. This pathway may guide new therapies for multiple sclerosis and other neurological disorders.

Pregnancy and post-partum in patients with myelin-oligodendrocyte glycoprotein antibody-associated disease.

BACKGROUND AND OBJECTIVE: Myelin-oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) frequently initiates during childbearing years. This study investigated the impact of pregnancy and post-partum on MOGAD activity. METHODS: Retrospective analysis of clinical and demographic data from a multicenter French cohort of adult patients with MOGAD. All adult female patients who had a pregnancy after disease onset or in the year before disease onset were included. The annualized relapse rate was evaluated in patients who had a pregnancy after disease onset, to evaluate the impact of pregnancy and post-partum on MOGAD course. RESULTS: Twenty-five informative pregnancies after disease onset were identified. No relapse was recorded during these pregnancies and only three relapses occurred during the first 3 months post-partum. The annualized relapse rate decreased from 0.67 (95% confidence interval: 0.40-1.10) during the pre-pregnancy period to 0 (95% confidence interval: 0-0.21) during pregnancy and to 0.22 (95% confidence interval: 0.09-0.53) during the first year post-partum. Among 144 female patients in their childbearing age recorded in the database, 18 (12.5%) reported their first symptoms during pregnancy or in the 12 months post-partum. DISCUSSION: Our study suggests a marked reduction of MOGAD relapse rate during pregnancy and the post-partum period. Prospective studies on the role of pregnancy and delivery in MOGAD course are needed.

Pregnancy and multiple sclerosis: 2022 recommendations from the French multiple sclerosis society.

OBJECTIVE: The objective of this study was to develop evidence-based recommendations on pregnancy management for persons with multiple sclerosis (MS). BACKGROUND: MS typically affects young women in their childbearing years. Increasing evidence is available to inform questions raised by MS patients and health professionals about pregnancy issues. METHODS: The French Group for Recommendations in Multiple Sclerosis (France4MS) reviewed PubMed and university databases (January 1975 through June 2021). The RAND/UCLA appropriateness method was developed to synthesise the scientific literature and expert opinions on healthcare topics; it was used to reach a formal agreement. Fifty-six MS experts worked on the full-text review and initial wording of recommendations. A group of 62 multidisciplinary healthcare specialists validated the final proposal of summarised evidence. RESULTS: A strong agreement was reached for all 104 proposed recommendations. They cover diverse topics, such as pregnancy planning, follow-up during pregnancy and postpartum, delivery routes, locoregional analgesia or anaesthesia, prevention of postpartum relapses, breastfeeding, vaccinations, reproductive assistance, management of relapses and disease-modifying treatments. CONCLUSION: The 2022 recommendations of the French MS society should be helpful to harmonise counselling and treatment practice for pregnancy in persons with MS, allowing for better and individualised choices.

Improving the decision to switch from first- to second-line therapy in multiple sclerosis: A dynamic scoring system.

BACKGROUND: In relapsing-remitting multiple sclerosis (RRMS), early identification of suboptimal responders can prevent disability progression. OBJECTIVE: We aimed to develop and validate a dynamic score to guide the early decision to switch from first- to second-line therapy. METHODS: Using time-dependent propensity scores (PS) from a French cohort of 12,823 patients with RRMS, we constructed one training and two validation PS-matched cohorts to compare the switched patients to second-line treatment and the maintained patients. We used a frailty Cox model for predicting individual hazard ratios (iHRs). RESULTS: From the validation PS-matched cohort of 348 independent patients with iHR ⩽ 0.69, we reported the 5-year relapse-free survival at 0.14 (95% confidence interval (CI) 0.09-0.22) for the waiting group and 0.40 (95% CI 0.32-0.51) for the switched group. From the validation PS-matched cohort of 518 independent patients with iHR > 0.69, these values were 0.37 (95% CI 0.30-0.46) and 0.44 (95% CI 0.37-0.52), respectively. CONCLUSIONS: By using the proposed dynamic score, we estimated that at least one-third of patients could benefit from an earlier switch to prevent relapse.

Pregnancy and neuromyelitis optica spectrum disorders: 2022 recommendations from the French Multiple Sclerosis Society.

BACKGROUND: In 2020, the French Multiple Sclerosis (MS) Society (SFSEP) decided to develop a national evidence-based consensus on pregnancy in MS. As neuromyelitis optica spectrum disorders (NMOSD) shares a series of commonalities with MS, but also some significant differences, specific recommendations had to be developed. OBJECTIVES: To establish recommendations on pregnancy in women with NMOSD. METHODS: The French Group for Recommendations in Multiple Sclerosis (France4MS) reviewed PubMed and universities databases (January 1975 through June 2021). The RAND/UCLA appropriateness method, which was developed to synthesise the scientific literature and expert opinions on health care topics, was used to reach a formal agreement. Fifty-six MS experts worked on the full-text review and initial wording of recommendations. A sub-group of nine NMOSD experts was dedicated to analysing available data on NMOSD. A group of 62 multidisciplinary healthcare specialists validated the final proposal of summarised evidence. RESULTS: A strong agreement was reached for all 66 proposed recommendations. They cover diverse topics, such as pregnancy planning, follow-up during pregnancy and postpartum, delivery routes, loco-regional analgesia or anaesthesia, prevention of postpartum relapses, breastfeeding, vaccinations, reproductive assistance, management of relapses, and disease-modifying treatments. CONCLUSION: Physicians and patients should be aware of the new and specific evidence-based recommendations of the French MS Society for pregnancy in women with NMOSD. They should help harmonise counselling and treatment practise, allowing for better individualised choices.

Semi-supervised clustering of quaternion time series: Application to gait analysis in multiple sclerosis using motion sensor data.

Recent approaches in gait analysis involve the use of wearable motion sensors to extract spatio-temporal parameters that characterize multiple aspects of an individual's gait. In particular, the medical community could largely benefit from this type of devices as they could provide the clinicians with a valuable tool for assessing gait impairment. Motion sensor data are however complex and there is an urgent unmet need to develop sound statistical methods for analyzing such data and extracting clinically relevant information. In this article, we measure gait by following the hip rotation over time and the resulting statistical unit is a time series of unit quaternions. We explore the possibility to form groups of patients with similar walking impairment by taking into account their walking data and their global decease severity with semi-supervised clustering. We generalize a compromise-based method named hclustcompro to unit quaternion time series by combining it with the proper dissimilarity quaternion dynamic time warping. We apply this method on patients diagnosed with multiple sclerosis to form groups of patients with similar walking deficiencies while accounting for the clinical assessment of their overall disability. We also compare the compromise-based clustering approach with the method mergeTrees that falls into a sub-class of ensemble clustering named collaborative clustering. The results provide a first proof of both the interest of using wearable motion sensors for assessing gait impairment and the use of prior knowledge to guide the clustering process. It also demonstrates that compromise-based clustering is a more appropriate approach in this context.

Effector Memory-Expressing CD45RA (TEMRA) CD8+ T Cells from Kidney Transplant Recipients Exhibit Enhanced Purinergic P2X4 Receptor-Dependent Proinflammatory and Migratory Responses.

BACKGROUND: The mechanisms regulating CD8+ T cell migration to nonlymphoid tissue during inflammation have not been fully elucidated, and the migratory properties of effector memory CD8+ T cells that re-express CD45RA (TEMRA CD8+ T cells) remain unclear, despite their roles in autoimmune diseases and allotransplant rejection. METHODS: We used single-cell proteomic profiling and functional testing of CD8+ T cell subsets to characterize their effector functions and migratory properties in healthy volunteers and kidney transplant recipients with stable or humoral rejection. RESULTS: We showed that humoral rejection of a kidney allograft is associated with an accumulation of cytolytic TEMRA CD8+ T cells in blood and kidney graft biopsies. TEMRA CD8+ T cells from kidney transplant recipients exhibited enhanced migratory properties compared with effector memory (EM) CD8+ T cells, with enhanced adhesion to activated endothelium and transmigration in response to the chemokine CXCL12. CXCL12 directly triggers a purinergic P2×4 receptor-dependent proinflammatory response of TEMRA CD8+ T cells from transplant recipients. The stimulation with IL-15 promotes the CXCL12-induced migration of TEMRA and EM CD8+ T cells and promotes the generation of functional PSGL1, which interacts with the cell adhesion molecule P-selectin and adhesion of these cells to activated endothelium. Although disruption of the interaction between functional PSGL1 and P-selectin prevents the adhesion and transmigration of both TEMRA and EM CD8+ T cells, targeting VLA-4 or LFA-1 (integrins involved in T cell migration) specifically inhibited the migration of TEMRA CD8+ T cells from kidney transplant recipients. CONCLUSIONS: Our findings highlight the active role of TEMRA CD8+ T cells in humoral transplant rejection and suggest that kidney transplant recipients may benefit from therapeutics targeting these cells.

Treatment regimens for neuromyelitis optica spectrum disorder attacks: a retrospective cohort study.

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) attacks require an urgent probabilistic anti-inflammatory therapeutic strategy. As inadequately treated attacks result in disability, there is a need to identify the optimal attack-treatment regimen. Our study aimed to identify predictors of outcome after a first attack in patients with an NMOSD presentation and propose the best treatment strategy. METHODS: We performed a retrospective cohort study on the French national NMOSD registry (NOMADMUS), a nested cohort of the French multiple sclerosis observatory (OFSEP) recruiting patients with NMOSD presentations in France. We studied the first attack for any independent locations of clinical core characteristic of NMOSD, in treatment-naïve patients. The primary outcome was the evolution of the Expanded Disability Status Scale (EDSS) score at 6 months, stratified in two ways to account for recovery (return to baseline EDSS score) and treatment response (classified 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). We used ordinal logistic regression to infer statistical associations with the outcome. RESULTS: We included 211 attacks among 183 patients (104 with anti-AQP4 antibodies, 60 with anti-MOG antibodies, and 19 double seronegative). Attack treatment regimens comprised corticosteroids (n = 196), plasma exchanges (PE; n = 72) and intravenous immunoglobulins (n = 6). Complete recovery was reached in 40 attacks (19%) at 6 months. The treatment response was "good" in 134 attacks (63.5%). There was no improvement in EDSS score in 50 attacks (23.7%). MOG-antibody seropositivity and short delays to PE were significantly and independently associated with better recovery and treatment response. CONCLUSIONS: We identified two prognostic factors: serostatus (with better outcomes among MOG-Ab-positive patients) and the delay to PE. We, therefore, argue for a more aggressive anti-inflammatory management of the first attacks suggesting an NMOSD presentation, with the early combination of PE with corticosteroids.

Cytotoxic CD8+ T lymphocytes expressing ALS-causing SOD1 mutant selectively trigger death of spinal motoneurons.

Adaptive immune response is part of the dynamic changes that accompany motoneuron loss in amyotrophic lateral sclerosis (ALS). CD4+ T cells that regulate a protective immunity during the neurodegenerative process have received the most attention. CD8+ T cells are also observed in the spinal cord of patients and ALS mice although their contribution to the disease still remains elusive. Here, we found that activated CD8+ T lymphocytes infiltrate the central nervous system (CNS) of a mouse model of ALS at the symptomatic stage. Selective ablation of CD8+ T cells in mice expressing the ALS-associated superoxide dismutase-1 (SOD1)G93A mutant decreased spinal motoneuron loss. Using motoneuron-CD8+ T cell coculture systems, we found that mutant SOD1-expressing CD8+ T lymphocytes selectively kill motoneurons. This cytotoxicity activity requires the recognition of the peptide-MHC-I complex (where MHC-I represents major histocompatibility complex class I). Measurement of interaction strength by atomic force microscopy-based single-cell force spectroscopy demonstrated a specific MHC-I-dependent interaction between motoneuron and SOD1G93A CD8+ T cells. Activated mutant SOD1 CD8+ T cells produce interferon-γ, which elicits the expression of the MHC-I complex in motoneurons and exerts their cytotoxic function through Fas and granzyme pathways. In addition, analysis of the clonal diversity of CD8+ T cells in the periphery and CNS of ALS mice identified an antigen-restricted repertoire of their T cell receptor in the CNS. Our results suggest that self-directed immune response takes place during the course of the disease, contributing to the selective elimination of a subset of motoneurons in ALS.

Single-Cell Analysis to Better Understand the Mechanisms Involved in MS.

Multiple sclerosis is a chronic and inflammatory disease of the central nervous system. Although this disease is widely studied, many of the precise mechanisms involved are still not well known. Numerous studies currently focusing on multiple sclerosis highlight the involvement of many major immune cell subsets, such as CD4+ T cells, CD8+ T cells and more recently B cells. However, our vision of its pathology has remained too broad to allow the proper use of targeted therapeutics. This past decade, new technologies have emerged, enabling deeper research into the different cell subsets at the single-cell level both in the periphery and in the central nervous system. These technologies could allow us to identify new cell populations involved in the disease process and new therapeutic targets. In this review, we briefly introduce the major single-cell technologies currently used in studies before diving into the major findings from the multiple sclerosis research from the past 5 years. We focus on results that were obtained using single-cell technologies to study immune cells and cells from the central nervous system.

Cumulative effects of therapies on disability in relapsing multiple sclerosis.

BACKGROUND: Long-term effectiveness of treatment remains a key question in multiple sclerosis (MS) and the cumulative effects of past treatment have not been investigated so far. OBJECTIVE: Explore the relationship between treatment exposure and disability risk in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: A total of 2285 adult patients from the French nationwide cohort were included. Outcomes were irreversible EDSS4, and conversion to secondary progression of multiple sclerosis (SPMS). Associations between treatments and risk of disability were assessed using a novel weighted cumulative exposure model, assuming a 3-year lag to account for reverse causality. This flexible approach accounts for past exposure in a multivariate Cox proportional hazards model by computing a weight function. RESULTS: At baseline, mean ± standard deviation age of patients was 33.4 ± 8.9 years and 75.0% were women. A 15-year continuous treatment starting 20 years ago was associated with a decrease in risk of 26% for irreversible EDSS4, and 34% for SPMS compared to a 5-year treatment starting 10 years ago. The risk of disability decreased with increasing duration of exposure to disease-modifying treatment (DMT). CONCLUSION: Long-term use of treatments in RRMS has a stronger beneficial cumulative impact than only early uses and delays the occurrence of moderate disability and conversion to SPMS.

BEST-MS: A prospective head-to-head comparative study of natalizumab and fingolimod in active relapsing MS.

BACKGROUND: There are few head-to-head studies to compare highly active treatments in multiple sclerosis (MS). OBJECTIVE: The aim of this study was to compare the effectiveness between natalizumab (NTZ) and fingolimod (FTY) in active relapsing-remitting MS. METHOD: Best Escalation STrategy in Multiple Sclerosis (BEST-MS) is a multicentric, prospective study with a 12-month follow-up including patients with active MS. Treatment choice was at the discretion of physician. Clinical and magnetic resonance imaging (MRI) data were collected at baseline and at 12 months. The primary outcome was the proportion of patients reaching no evidence of disease activity (NEDA) at 12 months. Secondary outcomes included annualized relapse rate and MRI activity. RESULTS: A total of 223 patients were included (NTZ: 109 and FTY: 114). Treatment groups were well balanced at baseline. Proportion of NEDA patients was 47.8% in NTZ group versus 30.4% in FTY group (p = 0.015). This superiority was driven by annualized relapse rate and MRI activity. In the multivariate analysis, treatment group was the only factor associated with NEDA at 12 months with a lower probability in FTY group (odds ratio (OR) = 0.49, p = 0.029). CONCLUSION: BEST-MS is a prospective study that compared head-to-head the effectiveness of NTZ and FTY in active relapsing-remitting MS. Our results suggest a superiority of NTZ over FTY.

Oral nomegestrol acetate and transdermal 17-beta-estradiol for preventing post-partum relapses in multiple sclerosis: The POPARTMUS study.

BACKGROUND: Sex steroids could explain the course of multiple sclerosis (MS) in pregnancy. OBJECTIVE: To compare the annualized relapse rate (ARR) 12 weeks post-partum in women treated with nomegestrol acetate (NOMAc) and 17-beta-estradiol (E2) versus placebo. METHODS: POPARTMUS is a randomized, proof-of-concept trial in women with MS, receiving oral NOMAc 10 mg/day and transdermal estradiol 75 µg/week, or placebo. RESULTS: Recruitment was stopped prematurely due to slow inclusions (n = 202). No treatment effect was observed on ARR after 12 weeks (sex steroids = 0.90 (0.58-1.39), placebo = 0.97 (0.63-1.50) (p = 0.79)). CONCLUSION: POPARTMUS failed showing efficacy of a NOMAc-E2 combination in preventing post-partum relapses.

Determinants of therapeutic lag in multiple sclerosis.

BACKGROUND: A delayed onset of treatment effect, termed therapeutic lag, may influence the assessment of treatment response in some patient subgroups. OBJECTIVES: The objective of this study is to explore the associations of patient and disease characteristics with therapeutic lag on relapses and disability accumulation. METHODS: Data from MSBase, a multinational multiple sclerosis (MS) registry, and OFSEP, the French MS registry, were used. Patients diagnosed with MS, minimum 1 year of exposure to MS treatment and 3 years of pre-treatment follow-up, were included in the analysis. Studied outcomes were incidence of relapses and disability accumulation. Therapeutic lag was calculated using an objective, validated method in subgroups stratified by patient and disease characteristics. Therapeutic lag under specific circumstances was then estimated in subgroups defined by combinations of clinical and demographic determinants. RESULTS: High baseline disability scores, annualised relapse rate (ARR) ⩾ 1 and male sex were associated with longer therapeutic lag on disability progression in sufficiently populated groups: females with expanded disability status scale (EDSS) < 6 and ARR < 1 had mean lag of 26.6 weeks (95% CI = 18.2-34.9), males with EDSS < 6 and ARR < 1 31.0 weeks (95% CI = 25.3-36.8), females with EDSS < 6 and ARR ⩾ 1 44.8 weeks (95% CI = 24.5-65.1), and females with EDSS ⩾ 6 and ARR < 1 54.3 weeks (95% CI = 47.2-61.5). CONCLUSIONS: Pre-treatment EDSS and ARR are the most important determinants of therapeutic lag.

The long-term outcome of MOGAD: An observational national cohort study of 61 patients.

BACKGROUND AND OBJECTIVE: The prognosis in myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a matter of debate. Our aim was to assess the long-term outcomes of patients with MOGAD. METHODS: We retrospectively analysed the clinical and paraclinical data of patients from the French nationwide observatory study NOMADMUS who tested positive for MOG antibodies (MOG-IgG) and who had clinical follow-up of at least 8 years from their first episode. RESULTS: Sixty-one patients (median [range] age at onset 27 [3-69] years), with a median (mean; range) follow-up of 177 (212.8; 98-657) months, were included. Among 58 patients with a relapsing course, 26.3% relapsed in the first year after onset. Of the 61 patients, 90.2% experienced at least one episode of optic neuritis. At last visit, the median (mean; range) Expanded Disability Status Scale (EDSS) score was 1 (2.12; 0-7.5), 12.5% had an EDSS score ≥6 and 37.5% had an EDSS score ≥3. Of 51 patients with final visual acuity (VA) data available, 15.7% had VA ≤0.1 in at least one eye and 25.5% had VA ≤0.5 in at least one eye. Bilateral blindness (VA ≤0.1) was present in 5.9% of patients. Finally, 12.5% of patients presented bladder dysfunction requiring long-term urinary catheterization. No factor associated significantly with a final EDSS score ≥3 or with final VA ≤0.1 was found. CONCLUSION: Overall long-term favourable outcomes were achieved in a majority of our patients, but severe impairment, in particular visual damage, was not uncommon.

Untreated patients with multiple sclerosis: A study of French expert centers.

BACKGROUND AND PURPOSE: Disease-modifying therapies (DMTs) have an impact on relapses and disease progression. Nonetheless, many patients with multiple sclerosis (MS) remain untreated. The objectives of the present study were to determine the proportion of untreated patients with MS followed in expert centers in France and to determine the predictive factors of nontreatment. METHODS: We conducted a retrospective cohort study. Data were extracted from the 38 centers participating in the European Database for Multiple Sclerosis (EDMUS) on December 15, 2018, and patients with MS seen at least once during the study period (from June 15, 2016 to June 14, 2017) were included. RESULTS: Of the 21,189 patients with MS (age 47.1 ± 13.1 years; Expanded Disability Status Scale (EDSS) score 3.4 ± 2.4), 6,631 (31.3%; 95% confidence interval [CI] 30.7-31.9) were not receiving any DMT. Although patients with a relapsing-remitting course (n = 11,693) were the most likely to receive DMT, 14.8% (95% CI 14.2-15.4) were still untreated (6.8% never treated). After multivariate analysis among patients with relapsing-remitting MS, the main factors explaining never having been treated were: not having ≥9 lesions on brain magnetic resonance imaging (odds ratio [OR] 0.52 [95% CI 0.44-0.61]) and lower EDSS score (OR 0.78 [95% CI 0.74-0.82]). Most patients with progressive MS (50.4% for secondary and 64.2% for primary progressive MS) did not receive any DMT during the study period, while 11.6% of patients with secondary and 34.0% of patients with primary progressive MS had never received any DMT. CONCLUSION: A significant proportion of patients with MS did not receive any DMT, even though such treatments are reimbursed by the healthcare system for French patients. This result highlights the unmet need for current DMTs for a large subgroup of patients with MS.

Integrative molecular profiling of autoreactive CD4 T cells in autoimmune hepatitis.

BACKGROUND & AIMS: In most autoimmune disorders, crosstalk of B cells and CD4 T cells results in the accumulation of autoantibodies. In autoimmune hepatitis (AIH), the presence of anti-soluble liver antigen (SLA) autoantibodies is associated with reduced overall survival, but the associated autoreactive CD4 T cells have not yet been characterised. Herein, we isolated and deeply characterised SLA-specific CD4 T cells in patients with AIH. METHODS: We used brief ex vivo restimulation with overlapping SLA peptides to isolate and phenotype circulating SLA-specific CD4 T cells, and integrative single-cell RNA-seq (scRNA-seq) to characterise their transcriptome and T-cell receptor (TCR) repertoire. Autoreactive TCRs were cloned and used to identify dominant SLA-derived epitopes. SLA-specific CD4 T cells were tracked in peripheral blood through TCR sequencing to identify their phenotypic niche. We further characterised disease-associated peripheral blood T cells by high-content flow cytometry in 42 patients with AIH and 17 controls with non-alcoholic steatohepatitis. RESULTS: Autoreactive SLA-specific CD4 T cells were only detected in patients with anti-SLA autoantibodies and had a memory PD-1+CXCR5-CCR6-CD27+ phenotype. ScRNA-seq revealed their pro-inflammatory/B-helper profile. SLA81-100 and SLA177-204 contain dominant T-cell epitopes. Autoreactive TCR clonotypes were predominantly found in the memory PD-1+CXCR5-CD4 T cells, which were significantly increased in the blood of patients with AIH and supported B-cell differentiation through IL-21. Finally, we identified specific T-cell phenotypes linked to disease activity and IgG level during AIH. CONCLUSIONS: We provide a deep characterisation of rare circulating autoreactive CD4 T cells and identify their peripheral reservoir in AIH. We also propose a specific phenotype of autoreactive T cells related to AIH disease activity, which will be essential to track, delineate, and potentially target these pathogenic cells. LAY SUMMARY: One principal characteristic of autoimmune hepatitis (AIH), like for many other autoimmune diseases, is the accumulation of autoantibodies produced by B lymphocytes following their interaction with autoreactive CD4 T lymphocytes. In this study, we identified and characterised with high resolution these CD4 T cells. This will be essential to track, delineate, and potentially target them during AIH.