MicroRNAs dysregulated in multiple sclerosis affect the differentiation of CG-4 cells, an oligodendrocyte progenitor cell line

IntroductionDemyelination is one of the hallmarks of multiple sclerosis (MS). While remyelination occurs during the disease, it is incomplete from the start and strongly decreases with its progression, mainly due to the harm to oligodendrocyte progenitor cells (OPCs), causing irreversible neurological deficits and contributing to neurodegeneration. Therapeutic strategies promoting remyelination are still very preliminary and lacking within the current treatment panel for MS.MethodsIn a previous study, we identified 21 microRNAs dysregulated mostly in the CSF of relapsing and/or remitting MS patients. In this study we transfected the mimics/inhibitors of several of these microRNAs separately in an OPC cell line, called CG-4. We aimed (1) to phenotypically characterize their effect on OPC differentiation and (2) to identify corroborating potential mRNA targets via immunocytochemistry, RT-qPCR analysis, RNA sequencing, and Gene Ontology enrichment analysis.ResultsWe observed that the majority of 13 transfected microRNA mimics decreased the differentiation of CG-4 cells. We demonstrate, by RNA sequencing and independent RT-qPCR analyses, that miR-33-3p, miR-34c-5p, and miR-124-5p arrest OPC differentiation at a late progenitor stage and miR-145-5p at a premyelinating stage as evidenced by the downregulation of premyelinating oligodendrocyte (OL) [Tcf7l2, Cnp (except for miR-145-5p)] and mature OL (Plp1, Mbp, and Mobp) markers, whereas only miR-214-3p promotes OPC differentiation. We further propose a comprehensive exploration of their change in cell fate through Gene Ontology enrichment analysis. We finally confirm by RT-qPCR analyses the downregulation of several predicted mRNA targets for each microRNA that possibly support their effect on OPC differentiation by very distinctive mechanisms, of which some are still unexplored in OPC/OL physiology.ConclusionmiR-33-3p, miR-34c-5p, and miR-124-5p arrest OPC differentiation at a late progenitor stage and miR-145-5p at a premyelinating stage, whereas miR-214-3p promotes the differentiation of CG-4 cells. We propose several potential mRNA targets and hypothetical mechanisms by which each microRNA exerts its effect. We hereby open new perspectives in the research on OPC differentiation and the pathophysiology of demyelination/remyelination, and possibly even in the search for new remyelinating therapeutic strategies in the scope of MS

Extensive Spinal Cord Injury following Staphylococcus aureus Septicemia and Meningitis

Bacterial meningitis is rarely complicated by spinal cord involvement in adults. We report a case of Staphylococcus aureus septicemia complicated by meningitis and extensive spinal cord injury, leading to ascending brain stem necrosis and death. This complication was investigated by magnetic resonance imaging which demonstrated intramedullary hyperintensity on T2-weighted images and by multimodality evoked potentials. Postmortem microscopic examination confirmed that the extensive spinal cord injury was of ischemic origin, caused by diffuse leptomeningitis and endarteritis

Konsensusprotokoll zur Standardisierung von Entnahme und Biobanking des Liquor cerebrospinalis

Die Erforschung von Biomarkern in Körperflüssigkeiten bei neurodegenerativen und neuroinflammatorischen Erkrankungen blickt auf eine langjährige Geschichte zurück. Dennoch werden nur wenige Liquor cerebrospinalis (Liquor)-Biomarker in der klinischen Praxis verwendet. Einer der problematischen Faktoren in der Liquorbiomarker-Forschung ist die eingeschränkte Aussagekraft von Studien aufgrund einer nicht ausreichend großer Anzahl von Proben, die in Studien von einzelnen Zentren akquiriert werden können. Deshalb ist die Kooperation zwischen mehreren Zentren erforderlich, um große Biobanken von definierten Proben zu etablieren. Standardisierte Protokolle für Biobanking sind unumgänglich, um die durch die größere Anzahl von Liquorproben gewonnene statistische Aussagekraft sicherzustellen und nicht durch mangelhafte Präanalytik einzuschränken. Hier wird ein Konsensusbericht über Leitlinien zu Liquorentnahme und Biobanking durch das BioMS-eu Netzwerk für Liquorbiomarker-Forschung in Multipler Sklerose präsentiert. Schwerpunkte des Berichts sind Liquorentnahme, präanalytische Faktoren und klinische sowie sonstige Informationen. Biobanking-Protokolle sind für Liquor-Biobanken im Rahmen der Erforschung jeder neurologischen Krankheit anwendba

Consensus Guidelines for CSF and Blood Biobanking for CNS Biomarker Studies

There is a long history of research into body fluid biomarkers in neurodegenerative and neuroinflammatory diseases. However, only a few biomarkers in cerebrospinal fluid (CSF) are being used in clinical practice. Anti-aquaporin-4 antibodies in serum are currently useful for the diagnosis of neuromyelitis optica (NMO), but we could expect novel CSF biomarkers that help define prognosis and response to treatment for this disease. One of the most critical factors in biomarker research is the inadequate powering of studies performed by single centers. Collaboration between investigators is needed to establish large biobanks of well-defined samples. A key issue in collaboration is to establish standardized protocols for biobanking to ensure that the statistical power gained by increasing the numbers of CSF samples is not compromised by pre-analytical factors. Here, consensus guidelines for CSF collection and biobanking are presented, based on the guidelines that have been published by the BioMS-eu network for CSF biomarker research. We focussed on CSF collection procedures, pre-analytical factors and high quality clinical and paraclinical information. Importantly, the biobanking protocols are applicable for CSF biobanks for research targeting any neurological disease

Natalizumab, Fingolimod and Dimethyl Fumarate Use and Pregnancy-Related Relapse and Disability in Women With Multiple Sclerosis

To investigate pregnancy-related disease activity in a contemporary multiple sclerosis (MS) cohort

Diagnostic value of kappa free light chain index in patients with primary progressive multiple sclerosis – a multicentre study

BackgroundKappa free light chains (κ-FLC) in the cerebrospinal fluid (CSF) are an emerging biomarker in multiple sclerosis (MS).ObjectiveTo investigate whether κ-FLC index has similar diagnostic value in patients with primary progressive multiple sclerosis (PPMS) compared to oligoclonal bands (OCB).MethodsPatients with PPMS were recruited through 11 MS centres across 7 countries. κ-FLC were measured by immunonephelometry/-turbidimetry. OCB were determined by isoelectric focusing and immunofixation.ResultsA total of 174 patients (mean age of 52±11 years, 51% males) were included. κ-FLC index using a cut-off of 6.1 was positive in 161 (93%) and OCB in 153 (88%) patients.Conclusionκ-FLC index shows similar diagnostic sensitivity than OCB in PPMS

Country, Sex, EDSS Change and Therapy Choice Independently Predict Treatment Discontinuation in Multiple Sclerosis and Clinically Isolated Syndrome

We conducted a prospective study, MSBASIS, to assess factors leading to first treatment discontinuation in patients with a clinically isolated syndrome (CIS) and early relapsing-remitting multiple sclerosis (RRMS). The MSBASIS Study, conducted by MSBase Study Group members, enrols patients seen from CIS onset, reporting baseline demographics, cerebral magnetic resonance imaging (MRI) features and Expanded Disability Status Scale (EDSS) scores. Follow-up visits report relapses, EDSS scores, and the start and end dates of MS-specific therapies. We performed a multivariable survival analysis to determine factors within this dataset that predict first treatment discontinuation. A total of 2314 CIS patients from 44 centres were followed for a median of 2.7 years, during which time 1247 commenced immunomodulatory drug (IMD) treatment. Ninety percent initiated IMD after a diagnosis of MS was confirmed, and 10% while still in CIS status. Over 40% of these patients stopped their first IMD during the observation period. Females were more likely to cease medication than males (HR 1.36, p = 0.003). Patients treated in Australia were twice as likely to cease their first IMD than patients treated in Spain (HR 1.98, p = 0.001). Increasing EDSS was associated with higher rate of IMD cessation (HR 1.21 per EDSS unit, p<0.001), and intramuscular interferon-β-1a (HR 1.38, p = 0.028) and subcutaneous interferon-β-1a (HR 1.45, p = 0.012) had higher rates of discontinuation than glatiramer acetate, although this varied widely in different countries. Onset cerebral MRI features, age, time to treatment initiation or relapse on treatment were not associated with IMD cessation. In this multivariable survival analysis, female sex, country of residence, EDSS change and IMD choice independently predicted time to first IMD cessation

Natalizumab treatment shows low cumulative probabilities of confirmed disability worsening to EDSS milestones in the long-term setting.

Abstract Background Though the Expanded Disability Status Scale (EDSS) is commonly used to assess disability level in relapsing-remitting multiple sclerosis (RRMS), the criteria defining disability progression are used for patients with a wide range of baseline levels of disability in relatively short-term trials. As a result, not all EDSS changes carry the same weight in terms of future disability, and treatment benefits such as decreased risk of reaching particular disability milestones may not be reliably captured. The objectives of this analysis are to assess the probability of confirmed disability worsening to specific EDSS milestones (i.e., EDSS scores ≥3.0, ≥4.0, or ≥6.0) at 288 weeks in the Tysabri Observational Program (TOP) and to examine the impact of relapses occurring during natalizumab therapy in TOP patients who had received natalizumab for ≥24 months. Methods TOP is an ongoing, open-label, observational, prospective study of patients with RRMS in clinical practice. Enrolled patients were naive to natalizumab at treatment initiation or had received ≤3 doses at the time of enrollment. Intravenous natalizumab (300 mg) infusions were given every 4 weeks, and the EDSS was assessed at baseline and every 24 weeks during treatment. Results Of the 4161 patients enrolled in TOP with follow-up of at least 24 months, 3253 patients with available baseline EDSS scores had continued natalizumab treatment and 908 had discontinued (5.4% due to a reported lack of efficacy and 16.4% for other reasons) at the 24-month time point. Those who discontinued due to lack of efficacy had higher baseline EDSS scores (median 4.5 vs. 3.5), higher on-treatment relapse rates (0.82 vs. 0.23), and higher cumulative probabilities of EDSS worsening (16% vs. 9%) at 24 months than those completing therapy. Among 24-month completers, after approximately 5.5 years of natalizumab treatment, the cumulative probabilities of confirmed EDSS worsening by 1.0 and 2.0 points were 18.5% and 7.9%, respectively (24-week confirmation), and 13.5% and 5.3%, respectively (48-week confirmation). The risks of 24- and 48-week confirmed EDSS worsening were significantly higher in patients with on-treatment relapses than in those without relapses. An analysis of time to specific EDSS milestones showed that the probabilities of 48-week confirmed transition from EDSS scores of 0.0–2.0 to ≥3.0, 2.0–3.0 to ≥4.0, and 4.0–5.0 to ≥6.0 at week 288 in TOP were 11.1%, 11.8%, and 9.5%, respectively, with lower probabilities observed among patients without on-treatment relapses (8.1%, 8.4%, and 5.7%, respectively). Conclusions In TOP patients with a median (range) baseline EDSS score of 3.5 (0.0–9.5) who completed 24 months of natalizumab treatment, the rate of 48-week confirmed disability worsening events was below 15%; after approximately 5.5 years of natalizumab treatment, 86.5% and 94.7% of patients did not have EDSS score increases of ≥1.0 or ≥2.0 points, respectively. The presence of relapses was associated with higher rates of overall disability worsening. These results were confirmed by assessing transition to EDSS milestones. Lower rates of overall 48-week confirmed EDSS worsening and of transitioning from EDSS score 4.0–5.0 to ≥6.0 in the absence of relapses suggest that relapses remain a significant driver of disability worsening and that on-treatment relapses in natalizumab-treated patients are of prognostic importance

Identification of a BRCA2-Specific modifier locus at 6p24 related to breast cancer risk

Common genetic variants contribute to the observed variation in breast cancer risk for BRCA2 mutation carriers; those known to date have all been found through population-based genome-wide association studies (GWAS). To comprehensively identify breast cancer risk modifying loci for BRCA2 mutation carriers, we conducted a deep replication of an ongoing GWAS discovery study. Using the ranked P-values of the breast cancer associations with the imputed genotype of 1.4 M SNPs, 19,029 SNPs were selected and designed for inclusion on a custom Illumina array that included a total of 211,155 SNPs as part of a multi-consortial project. DNA samples from 3,881 breast cancer affected and 4,330 unaffected BRCA2 mutation carriers from 47 studies belonging to the Consortium of Investigators of Modifiers of BRCA1/2 were genotyped and available for analysis. We replicated previously reported breast cancer susceptibility alleles in these BRCA2 mutation carriers and for several regions (including FGFR2, MAP3K1, CDKN2A/B, and PTHLH) identified SNPs that have stronger evidence of association than those previously published. We also identified a novel susceptibility allele at 6p24 that was inversely associated with risk in BRCA2 mutation carriers (rs9348512; per allele HR = 0.85, 95% CI 0.80-0.90, P = 3.9×10−8). This SNP was not associated with breast cancer risk either in the general population or in BRCA1 mutation carriers. The locus lies within a region containing TFAP2A, which encodes a transcriptional activation protein that interacts with several tumor suppressor genes. This report identifies the first breast cancer risk locus specific to a BRCA2 mutation background. This comprehensive update of novel and previously reported breast cancer susceptibility loci contributes to the establishment of a panel of SNPs that modify breast cancer risk in BRCA2 mutation carriers. This panel may have clinical utility for women with BRCA2 mutations weighing options for medical prevention of breast cancer

Prognostic indicators and outcomes of hospitalised COVID-19 patients with neurological disease: An individual patient data meta-analysis

BACKGROUND: Neurological COVID-19 disease has been reported widely, but published studies often lack information on neurological outcomes and prognostic risk factors. We aimed to describe the spectrum of neurological disease in hospitalised COVID-19 patients; characterise clinical outcomes; and investigate factors associated with a poor outcome. METHODS: We conducted an individual patient data (IPD) meta-analysis of hospitalised patients with neurological COVID-19 disease, using standard case definitions. We invited authors of studies from the first pandemic wave, plus clinicians in the Global COVID-Neuro Network with unpublished data, to contribute. We analysed features associated with poor outcome (moderate to severe disability or death, 3 to 6 on the modified Rankin Scale) using multivariable models. RESULTS: We included 83 studies (31 unpublished) providing IPD for 1979 patients with COVID-19 and acute new-onset neurological disease. Encephalopathy (978 [49%] patients) and cerebrovascular events (506 [26%]) were the most common diagnoses. Respiratory and systemic symptoms preceded neurological features in 93% of patients; one third developed neurological disease after hospital admission. A poor outcome was more common in patients with cerebrovascular events (76% [95% CI 67-82]), than encephalopathy (54% [42-65]). Intensive care use was high (38% [35-41]) overall, and also greater in the cerebrovascular patients. In the cerebrovascular, but not encephalopathic patients, risk factors for poor outcome included breathlessness on admission and elevated D-dimer. Overall, 30-day mortality was 30% [27-32]. The hazard of death was comparatively lower for patients in the WHO European region. INTERPRETATION: Neurological COVID-19 disease poses a considerable burden in terms of disease outcomes and use of hospital resources from prolonged intensive care and inpatient admission; preliminary data suggest these may differ according to WHO regions and country income levels. The different risk factors for encephalopathy and stroke suggest different disease mechanisms which may be amenable to intervention, especially in those who develop neurological symptoms after hospital admission