High-Efficacy Therapy Discontinuation vs Continuation in Patients 50 Years and Older With Nonactive MS.

Importance: A recent randomized clinical trial concluded that discontinuing medium-efficacy therapy might be a reasonable option for older patients with nonactive multiple sclerosis (MS), but there is a lack of data on discontinuing high-efficacy therapy (HET). In younger patients, the discontinuation of natalizumab and fingolimod is associated with a risk of rebound of disease activity. Objective: To determine whether discontinuing HET in patients 50 years and older with nonactive MS is associated with an increased risk of relapse compared with continuing HET. Design, Setting, and Participants: This observational cohort study used data from 38 referral centers from the French MS registry (Observatoire Français de la Sclérose en Plaques [OFSEP] database). Among 84704 patients in the database, data were extracted for 1857 patients 50 years and older with relapsing-remitting MS treated by HET and with no relapse or magnetic resonance imaging activity for at least 2 years. After verification of the medical records, 1620 patients were classified as having discontinued HET or having remained taking treatment and were matched 1:1 using a dynamic propensity score (including age, sex, disease phenotype, disability, treatment of interest, and time since last inflammatory activity). Patients were included from February 2008 to November 2021, with a mean (SD) follow-up of 5.1 (2.9) years. Data were extracted in June 2022. Exposures: Natalizumab, fingolimod, rituximab, and ocrelizumab. Main Outcomes and Measures: Time to first relapse. Results: Of 1620 included patients, 1175 (72.5%) were female, and the mean (SD) age was 54.7 (4.8) years. Among the 1452 in the HET continuation group and 168 in the HET discontinuation group, 154 patients in each group were matched using propensity scores (mean [SD] age, 57.7 [5.5] years; mean [SD] delay since the last inflammatory activity, 5.6 [3.8] years; mean [SD] follow-up duration after propensity score matching, 2.5 [2.1] years). Time to first relapse was significantly reduced in the HET discontinuation group compared with the HET continuation group (hazard ratio, 4.1; 95% CI, 2.0-8.5; P < .001) but differed between HETs, with a hazard ratio of 7.2 (95% CI, 2.1-24.5; P = .001) for natalizumab, 4.5 (95% CI, 1.3-15.5; P = .02) for fingolimod, and 1.1 (95% CI, 0.3-4.8; P = .85) for anti-CD20 therapy. Conclusion and Relevance: As in younger patients, in patients 50 years and older with nonactive MS, the risk of relapse increased significantly after stopping HETs that impact immune cell trafficking (natalizumab and fingolimod). There was no significant increase in risk after stopping HETs that deplete B-cells (anti-CD20 therapy). This result may inform decisions about stopping HETs in clinical practice.

Impact of automatic tools for detecting new lesions on therapeutic strategies offered to patients with MS by neurologists.

BACKGROUND: Automatic tools for detecting new lesions in patients with MS between two MRI scans are now available to clinicians. They have been assessed from the radiologist's point of view, but their impact on the therapeutic strategies that neurologists offer their patients has not yet been documented. OBJECTIVES: To compare neurologist's decisions according to whether a lesion detection support system had been used and describe variability between neurologists on decision-making for the same clinical cases. METHODS: We submitted 28 clinical cases associated with pairs of MRI images and radiological reports (produced by the same radiologist without vs. with the help of a system to detect new lesions) to 10 neurologists who regularly follow patients with MS. They examined each clinical case twice (without vs. with support system) in two sessions several weeks apart, and their patient management decisions were recorded. RESULTS: There was considerable variability between neurologists on decision-making (both with and without support system). When the support system had been used, neurologists more often made changes to patient management (75 % vs. 68 % of cases, p = 0.01) and spent significantly less time analyzing the clinical cases (249 s vs. 216 s, p == 3.10-4). CONCLUSION: The use of a lesion detection support system has an impact not only on radiologists' reports, but also on neurologists' subsequent decision-making. This observation constitutes another strong argument for promoting the wider use of such systems in clinical routine. However, despite their use, there is still considerable variability in decision-making across neurologists, which should encourage us to refine the guidelines.

The biological sample collection of the OFSEP French MS registry: An essential tool dedicated to researchers.

Today's medicine strives to be personalized, preventive, predictive and participatory. This implies to have access to multimodal data to better characterize patients groups and to combine clinical and imaging data with high-quality biological samples. Collecting such data is one of the objectives of the Observatoire français de la sclérose en plaques (OFSEP), the French MS registry. On December 2022, the OFSEP biocollection includes 4,888 patients with scientific characteristics and about 90,000 samples. Thanks to its richness, this biocollection open for the scientific community, contributes to address unmet needs in MS through identification of multiomics determinants of MS activity, progression and secondary effects.

Anti-CD20 therapies in multiple sclerosis: From pathology to the clinic.

The immune system plays a significant role in multiple sclerosis. While MS was historically thought to be T cell-mediated, multiple pieces of evidence now support the view that B cells are essential players in multiple sclerosis pathogenic processes. High-efficacy disease-modifying therapies that target the immune system have emerged over the past two decades. Anti-CD20 monoclonal antibodies selectively deplete CD20+ B and CD20+ T cells and efficiently suppress inflammatory disease activity. These monotherapies prevent relapses, reduce new or active magnetic resonance imaging brain lesions, and lessen disability progression in patients with relapsing multiple sclerosis. Rituximab, ocrelizumab, and ofatumumab are currently used in clinical practice, while phase III clinical trials for ublituximab have been recently completed. In this review, we compare the four anti-CD20 antibodies in terms of their mechanisms of action, routes of administration, immunological targets, and pharmacokinetic properties. A deeper understanding of the individual properties of these molecules in relation to their efficacy and safety profiles is critical for their use in clinical practice.

Pregnancy-related healthcare utilization among women with multiple sclerosis.

Introduction: Many studies have investigated pregnancy in women with multiple sclerosis (MS). However, no study has measured prenatal healthcare utilization in women with MS or adherence to follow-up recommendations to improve antenatal care quality. A better knowledge of the quality of antenatal care in women with MS would help identify and better support women with insufficient follow-up. Our objective was to measure the level of compliance to prenatal care recommendations in women with MS using data from the French National Health Insurance Database. Methods: This retrospective cohort study included all pregnant women with MS who gave live birth in France between 2010 and 2015. Using the French National Health Insurance Database, follow-up visits with gynecologists, midwives, and general practitioners (GPs) were identified, as well as ultrasound exams and laboratory tests. Based on the Adequacy of Prenatal Care Use and Content and Timing of care in Pregnancy indices, a new tool adapted to the French recommendations was developed to measure and classify the antenatal care trajectory (adequate or inadequate). Explicative factors were identified using multivariate logistic regression models. A random effect was included because women may have had more than one pregnancy during the study period. Results: In total, 4,804 women with MS (N = 5,448 pregnancies ending in live births) were included. When considering only visits with gynecologists/midwives, 2,277 pregnancies (41.8%) were considered adequate. When adding visits with GP, their number increased to 3,646 (66.9%). Multivariate models showed that multiple pregnancy and higher medical density were associated with better adherence to follow-up recommendations. Conversely, adherence was lower in 25-29-year-old and >40-year-old women, in women with very low income, and agricultural and self-employed workers. No visits, ultrasound exams, and laboratory tests were recorded in 87 pregnancies (1.6%). In 50% of pregnancies, women had at least one visit with a neurologist during the pregnancy, and women restarted disease-modifying therapy (DMT) within 6 months after delivery in 45.9% of pregnancies. Discussion: Many women consulted their GP during pregnancy. This could be linked to a low density of gynecologists but may also reflect the preferences of women. Our findings can help adapt recommendations and healthcare providers' practices according to the women's profiles.

Switching from natalizumab administration at the day hospital to administration at home. A 1 year prospective study of patient experience and quality of life in 30 consecutive patients with multiple sclerosis (TYSAD-35).

BACKGROUND: In the context of the COVID-19 pandemic, French health authorities allowed the home administration of natalizumab by a healthcare-at-home service. We evaluated the patients' perception of care quality following the transition from day-hospital to home natalizumab administration. METHODS: Thirty relapsing-remitting multiple sclerosis (MS) patients treated with natalizumab were prospectively evaluated for one year after changing onto a home treatment procedure, using MusiCare, the first MS-specific questionnaire to evaluate patient experience and MusiQol. A numerical rating scale score for satisfaction and a dedicated questionnaire concerning patient experience were completed after each infusion. The primary endpoint was the mean difference in MusiCare score between baseline and 12 months. RESULTS: From June 2020 to November 2021, 306 infusions were performed at home. Three patients withdrew from the study (one lost to follow-up and two preferred to return at the day hospital). No worsening of patient experience or quality of life was observed. The mean scores of the Musicare dimensions were higher at 12 months than at baseline, significantly for the "relationship with healthcare professionals" (p = 0.0203). The MusiQol global score remained stable but the coping and friendship dimensions were significantly better at M12 than at baseline (p = 0.0491 and p = 0.0478, respectively). The satisfaction questionnaire highlighted some pain during the infusions (21.8%) and contradictions between healthcare professionals (17.2%). The mean score for satisfaction with care was 9.1/10. No safety concerns were identified. CONCLUSION: The positive experience of patients with home natalizumab administration provides an important opportunity to improve the quality of patient care.

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.

Discontinuation of second- versus first-line disease-modifying treatment in middle-aged patients with multiple sclerosis.

BACKGROUND AND PURPOSE: There has been scant research on the consequences of discontinuing second-line disease-modifying treatment (DMT) in middle-aged patients with multiple sclerosis (MS). The objective was therefore to examine the occurrence of focal inflammatory activity after the discontinuation of second versus first-line DMT in patients over 45 years. METHODS: Patients who had been treated for at least 6 months with second (natalizumab, fingolimod, anti CD20) or first-line DMT and who stopped their DMT were retrospectively included. Kaplan-Meier survival curves were used to study the occurrence of relapse and MRI activity according to the type of DMT stopped. Proportional hazard Cox models were calculated to identify factors associated with focal inflammatory activity. The annualized relapse rate was calculated under treatment and for every 3 months after DMT discontinuation. RESULTS: We included 232 patients (median age: 52.8 years), 49 of whom stopped second-line DMT. The probability of having a relapse within the year following discontinuation was 6% for first-line DMT, 9% for fingolimod and 43% for natalizumab. In multivariate analysis, the probability of relapse after DMT discontinuation was significantly increased with natalizumab compared to first-line DMT (HR = 3.24; 95% CI [1.52; 6.90]). A peak of relapse was observed at 0-3 months after stopping natalizumab or fingolimod. CONCLUSION: Our study suggests that the risk of inflammatory activity is greater after discontinuation of natalizumab compared to other DMT even in middle-aged patients. As for younger patients, natalizumab discontinuation should only be considered if there is an adequate substitution of a different therapy. .

Multiple Sclerosis CSF Is Enriched With Follicular T Cells Displaying a Th1/Eomes Signature.

BACKGROUND AND OBJECTIVES: Tertiary lymphoid structures and aggregates are reported in the meninges of patients with multiple sclerosis (MS), especially at the progressive stage, and are strongly associated with cortical lesions and disability. Besides B cells, these structures comprise follicular helper T (Tfh) cells that are crucial to support B-cell differentiation. Tfh cells play a pivotal role in amplifying autoreactive B cells and promoting autoantibody production in several autoimmune diseases, but very few are known in MS. In this study, we examined the phenotype, frequency, and transcriptome of circulating cTfh cells in the blood and CSF of patients with relapsing-remitting MS (RRMS). METHODS: The phenotype and frequency of cTfh cells were analyzed in the blood of 39 healthy controls and 41 untreated patients with RRMS and in the CSF and paired blood of 10 patients with drug-naive RRMS at diagnosis by flow cytometry. Using an in vitro model of blood-brain barrier, we assessed the transendothelial migratory abilities of the different cTfh-cell subsets. Finally, we performed an RNA sequencing analysis of paired CSF cTfh cells and blood cTfh cells in 8 patients sampled at their first demyelinating event. RESULTS: The blood phenotype and frequency of cTfh cells were not significantly modified in patients with RRMS. In the CSF, we found an important infiltration of Tfh1 cells, with a high proportion of activated PD1+ cells. We demonstrated that the specific subset of Tfh1 cells presents increased migration abilities to cross an in vitro model of blood-brain barrier. Of interest, even at the first demyelinating event, cTfh cells in the CSF display specific characteristics with upregulation of EOMES gene and proinflammatory/cytotoxic transcriptomic signature able to efficiently distinguish cTfh cells from the CSF and blood. Finally, interactome analysis revealed potential strong cross talk between pathogenic B cells and CSF cTfh cells, pointing out the CSF as opportune supportive compartment and highlighting the very early implication of B-cell helper T cells in MS pathogenesis. DISCUSSION: Overall, CSF enrichment in activated Tfh1 as soon as disease diagnosis, associated with high expression of EOMES, and a predicted high propensity to interact with CSF B cells suggest that these cells probably contribute to disease onset and/or activity.

Disease modifying therapies and disease activity during pregnancy and postpartum in a contemporary cohort of relapsing Multiple Sclerosis patients.

BACKGROUND: In Multiple Sclerosis (MS) women, therapeutic management for pregnancy planning and during pregnancy still represents a challenge regarding timing of disease-modifying therapies (DMT) stop, risk of disease reactivation and potential fetal toxicity. The objective of this study was to describe disease activity during pregnancy and postpartum depending on treatment status before conception in women with MS. METHODS: 339 MS patients who have achieved a pregnancy between 2007 and 2017 were included. Women were classified according to their exposure to DMT in the 18 months period prior to pregnancy (untreated / first- / second/third-line treatment). RESULTS: 122 women were not exposed to DMT prior to conception, whereas 147 were exposed to first-line DMT and 70 to second/third line DMT (73% to natalizumab and 23% to fingolimod) before conception. In the first-line group, the ARR decreased from 0.39 during the year before conception to 0.21 during pregnancy, whereas it increased in the second/third-line group from 0.59 to 0.78. 47.1% of the second/third-line group faced at least one relapse during pregnancy and the time from conception to first relapse was significantly shorter in this group (p < 10-4). The risk of relapse during pregnancy and postpartum was associated with occurrence of pre-conception relapses and second/third line DMT exposure before pregnancy. CONCLUSION: Careful consideration should be given to natalizumab and fingolimod exposed patients before conception as they are at higher risk of reactivation of MS during pregnancy.

Disease reactivation after fingolimod cessation in Multiple Sclerosis patients with pregnancy desire: A retrospective study.

Reactivation of Multiple Sclerosis (MS) activity has been described after fingolimod cessation. Because of its contra indication during pregnancy, switch towards lower efficacy treatments are frequent in MS patients with childbearing desire but expose them to a risk of disease reactivation. In this retrospective study including 44 women with MS, a significant increase of the median annualized relapse rate was found in the year following fingolimod discontinuation compared to the period before (p < 0.0001), and 57% of women experienced at least one relapse. When considering to start fingolimod, particular attention should be paid to women with a short-term pregnancy desire.

COPP-MS: COrticosteroids during the Post-Partum in relapsing Multiple Sclerosis patients.

BACKGROUND: No specific treatment has demonstrated its effectiveness to prevent post-partum relapses for multiple sclerosis (MS) women. OBJECTIVE: To assess the effectiveness of preventive high-dose corticosteroids in the post-partum period by comparing two strategies: (1) no preventive treatment and (2) standardized preventive treatment. METHODS: We selected five French Multiple Sclerosis centers using the same post-partum strategy for their patients-either high-dose steroids (treating centers TC) or no treatment (non-treating centers NTC). We included relapsing-remitting multiple sclerosis women who delivered between January 2007 and January 2017. Our primary outcomes were the time from delivery to first relapse, EDSS progression and MRI activity between patients of treating centers and non-treating centers, after propensity-score weighting. RESULTS: 350 patients were included (116 from treating centers, 234 from non-treating centers). For both groups, the annualized relapse rate decreased during pregnancy (0.28 in treating centers and 0.34 in non-treating centers during the third trimester) and increased during the first post-partum trimester (0.45 and 0.69, respectively) with 11% and 14% (NS) of patients facing at least one relapse, respectively. Our primary outcomes were not statistically different between both groups. CONCLUSION: This study provides class III evidence that systematic high-dose corticosteroids are not associated with a reduced inflammatory activity during the post-partum period in multiple sclerosis patients.

Trends in disease-modifying therapy use in patients with multiple sclerosis using a 10-year population-based cohort study in France.

BACKGROUND: The availability of new disease-modifying therapies (DMTs) for patients with multiple sclerosis (MS) provides an opportunity for improving outcomes but makes disease management more complex. Our study aimed to describe changes in therapeutic practices over the period 2009-2018 and measure the impact of the arrival of oral DMTs on the use of injectable DMTs. METHODS: Data were extracted from a representative 1/97 sample of the French population covered by the healthcare insurance system. Study period was set from 1 January 2009 to 31 December 2018. Four periods of MS identification were defined (before 2009, 2009-2011, 2012-2015, and 2016-2018). RESULTS: Overall, 1,508 patients with MS were included, of whom 876 (58.1%) were treated at least once over the study period. Untreated patients were older and had more comorbidities than treated ones. First-line DMTs were the most frequent initial DMT (78.5%), and a shift has operated from injectable to oral drugs over time. The proportion of patients receiving several DMTs increased with the number of available drugs. End 2018, relative parts of all DMTs were almost equal. CONCLUSIONS: This study provides valuable insights into the real-world use of DMTs and changes that have operated over time.

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.

New concepts on immunology of Multiple Sclerosis.

Multiple sclerosis (MS) is a chronic inflammatory and immune-driven demyelinating disease of the central nervous system (CNS). During the past decade, major advances have been made to understand the development of MS as well as its progressive stage. Here, we discuss some emerging concepts on immunology of MS, including the growing interest in the involvement of gut microbiota and the recent pathological concepts on the progression phase. Finally, we present some immuno-tools recently available that contribute to better understand diversity and function of the immune system.

Severe cytomegalovirus disease with encephalitis after CAR-T cell therapy: A rare but potentially fatal complication.

Cytomegalovirus (CMV) is a ubiquitous herpes virus that develops lifelong latency following primary infection and can be reactivated following immune suppression. CMV encephalopathy has been described in few reports after hematopoietic stem cell transplantation and in patients with acquired immunodeficiency syndrome. To the best of our knowledge, CMV encephalopathy following CAR-T cells infusion had not been previously reported. Initial CMV viral load and monitoring are crucial in patients with CAR-T cells to allow early intervention with aggressive antiviral treatment without delay if needed.

CCR6 Expression on B Cells Is Not Required for Clinical or Pathological Presentation of MOG Protein-Induced Experimental Autoimmune Encephalomyelitis despite an Altered Germinal Center Response.

B cells have been implicated in the pathogenesis of multiple sclerosis, but the mechanisms that guide B cell activation in the periphery and subsequent migration to the CNS remain incompletely understood. We previously showed that systemic inflammation induces an accumulation of B cells in the spleen in a CCR6/CCL20-dependent manner. In this study, we evaluated the role of CCR6/CCL20 in the context of myelin oligodendrocyte glycoprotein (MOG) protein-induced (B cell-dependent) experimental autoimmune encephalomyelitis (EAE). We found that CCR6 is upregulated on murine B cells that migrate into the CNS during neuroinflammation. In addition, human B cells that migrate across CNS endothelium in vitro were found to be CCR6+, and we detected CCL20 production by activated CNS-derived human endothelial cells as well as a systemic increase in CCL20 protein during EAE. Although mice that lack CCR6 expression specifically on B cells exhibited an altered germinal center reaction in response to MOG protein immunization, CCR6-deficient B cells did not exhibit any competitive disadvantage in their migration to the CNS during EAE, and the clinical and pathological presentation of EAE induced by MOG protein was unaffected. These data, to our knowledge, provide new information on the role of B cell-intrinsic CCR6 expression in a B cell-dependent model of neuroinflammation.

[Autologous hematopoietic cells for severe autoimmune diseases: Guidelines of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) for immune monitoring and biobanking]. / Suivi immunologique et collection biologique en vue de l'analyse de la réponse clinique après autogreffe de moelle pour maladies auto-immunes : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

Autologous hematopoietic cell transplantation (AHCT) is a new treatment option for patients with severe autoimmune diseases (AD), based on the use of intensive or myeloablative chemotherapy to eradicate the pathogenic autoreactive immune cells and to allow the installation of a new and tolerant immune system during immune reconstitution process. Immune reconstitution analysis after AHCT is required for patients clinical follow-up and to further identify biological and immunological markers of the clinical response to develop individualized AHCT protocols. These MATHEC-SFGM-TC good clinical practice guidelines were developed by a multidisciplinary group of experts including members of the french reference center for stem Cell Therapy in Auto-immune Diseases (MATHEC), hematologists from the French speaking Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) and experts in immune monitoring and biobanking. The objectives are to provide practical recommandations for immune monitoring and biobanking of samples in patients with AD undergoing AHCT, for routine care purposes and investigational studies.