Central and peripheral myeloid-derived suppressor cell-like cells are closely related to the clinical severity of multiple sclerosis.

Multiple sclerosis (MS) is a highly heterogeneous demyelinating disease of the central nervous system (CNS) that needs for reliable biomarkers to foresee disease severity. Recently, myeloid-derived suppressor cells (MDSCs) have emerged as an immune cell population with an important role in MS. The monocytic-MDSCs (M-MDSCs) share the phenotype with Ly-6Chi-cells in the MS animal model, experimental autoimmune encephalomyelitis (EAE), and have been retrospectively related to the severity of the clinical course in the EAE. However, no data are available about the presence of M-MDSCs in the CNS of MS patients or its relation with the future disease aggressiveness. In this work, we show for the first time cells exhibiting all the bona-fide phenotypical markers of M-MDSCs associated with MS lesions, whose abundance in these areas appears to be directly correlated with longer disease duration in primary progressive MS patients. Moreover, we show that blood immunosuppressive Ly-6Chi-cells are strongly related to the future severity of EAE disease course. We found that a higher abundance of Ly-6Chi-cells at the onset of the EAE clinical course is associated with a milder disease course and less tissue damage. In parallel, we determined that the abundance of M-MDSCs in blood samples from untreated MS patients at their first relapse is inversely correlated with the Expanded Disability Status Scale (EDSS) at baseline and after a 1-year follow-up. In summary, our data point to M-MDSC load as a factor to be considered for future studies focused on the prediction of disease severity in EAE and MS.

Syncytin-1/HERV-W envelope is an early activation marker of leukocytes and is upregulated in multiple sclerosis patients.

Syncytin-1 is the envelope protein of the human endogenous retrovirus W (HERV-W). It has been related to multiple sclerosis (MS) but its role in cellular immunity and its pathogenic mechanism in the autoimmune context are not fully understood. We analyzed syncytin-1 levels in peripheral blood mononuclear cells (PBMC) subsets from healthy donors, MS patients in relapse or remission, and patients with acute infections by flow cytometry. PBMC cultures were also prepared to analyze protein expression kinetics. MS patients had higher levels of syncytin-1 levels than controls. We found that syncytin-1 is elevated in monocytes during MS relapses and infections. Cells expressing syncytin-1, including monocytes, T and B lymphocytes, and NKs presented mainly an activated phenotype and, upon stimulation with LPS, its levels increased rapidly on antigen-presenting cells. Syncytin-1 ligation promoted the activation of monocytes, as demonstrated by the upregulation of CD80 and the nonclassical subset CD14low CD16+ . Our results suggest an important role for syncytin-1 in the activation of leukocytes. Given that the expression of syncytin-1 is upregulated in MS patients, this protein might be contributing to the autoimmune cascade in the disease.

Study of the anti-JCV antibody levels in a Spanish multiple sclerosis cohort.

BACKGROUND: One of the risk factor to develop progressive multifocal leukoencephalopathy (PML) among natalizumab-treated patients is the presence and high levels of anti-JCV antibodies. Our purpose was to test the association of different clinical and demographic variables with the presence and levels of anti-JCV antibodies in a Spanish cohort of patients with multiple sclerosis (MS) during natalizumab treatment. MATERIALS AND METHODS: All patients with MS from two hospitals with at least one measure of the anti-JCV antibodies levels (2011-2014) were recruited, among them were two PML cases. Anti-JCV antibody levels were assessed using two-step ELISA. RESULTS: A total of 1061 patients (16·3% natalizumab-treated) participated in this study. The seropositivity rate of anti-JCV antibodies was 58·2%. It increased with age (Pcorrected = 0·00005) and was lower among HLA-DRB1*15:01 carriers (Pcorrected = 0·049). The two patients with PML were HLA-DRB1*15:01 carriers. We had at least three quarterly anti-JCV antibody measurements (index value) from 137 patients, whose levels did not increase during natalizumab treatment. However, 5·8% of these patients had an increase of the index value higher of one point in a maximum of 6 months, something that was more frequently observed (P = 0·054) among patients treated with immunosuppressant prior to natalizumab onset. CONCLUSIONS: Old age and HLA-DRB1*15:01 were the factors that influence positively and negatively, respectively, our anti-JCV antibody prevalence, although our both PML cases were HLA-DRB1*15:01carriers. Most of our patients showed a stable anti-JCV antibody index values during natalizumab treatment.

A two-years real-word study with fingolimod: early predictors of efficacy and an association between EBNA-1 IgG titers and multiple sclerosis progression.

Background: Although fingolimod, a sphingosine 1-phosphate receptor agonist, has shown to be an effective treatment reducing relapse rate and also slowing down the disability progression in relapsing-remitting multiple sclerosis (RRMS) patients, it is important to quickly identify those suboptimal responders. Objective: The main objective was to assess different clinical, radiological, genetic and environmental factors as possible early predictors of response in MS patients treated with fingolimod for 24 months. The secondary objective was to analyze the possible contribution of the environmental factors analyzed to the progression and activity of the disease along the 2-years of follow-up. Methods: A retrospective study with 151 patients diagnosed with MS, under fingolimod treatment for 24 months, with serum samples at initiation and six months later, and with clinical and radiological data at initiation and 24 months later, were included in the study. Clinical and radiological variables were collected to establish NEDA-3 (no evidence of disease activity: patients without relapses, disability progression and new T2 lesions or Gd+ lesions) and EDA (evidence of disease activity: patients with relapses and/or progression and/or new T2 lesions or gadolinium-positive [Gd+] lesions) conditions. Human leukocyte antigen II (HLA-II), EBNA-1 IgG and VCA IgG from Epstein-Barr virus (EBV) and antibody titers against Human herpesvirus 6A/B (HHV-6A/B) were also analyzed. Results: A total of 151 MS patients fulfilled the inclusion criteria: 27.8% was NEDA-3 (37.5% among those previously treated with high efficacy therapies >24 months). The following early predictors were statistically significantly associated with NEDA-3 condition: sex (male; p=0.002), age at baseline (older; p=0.009), relapses 2-years before fingolimod initiation ≤1 (p=0.010), and absence of Gd+ lesions at baseline (p=0.006). Regarding the possible contribution of the environmental factors included in the study to the activity or the progression of the disease, we only found that EBNA-1 IgG titers decreased in 20.0% of PIRA (progression independent from relapse activity) patients vs. 73.3% of RAW (relapse-associated worsening) patients (p=0.006; O.R. = 11.0). Conclusion: MS patients that are male, older, and with a low clinical and radiological activity at fingolimod initiation have a greater probability to reach NEDA-3 condition after two years with this therapy. An intriguing association of EBV with the progression of the disease has also been described, but it should be further study in a larger cohort to confirm these results.

Three-Year Effectiveness of Dimethyl Fumarate in Multiple Sclerosis: A Prospective Multicenter Real-World Study.

BACKGROUND: Dimethyl fumarate (DMF) has demonstrated efficacy in phase III studies. However, real-world data are still limited. OBJECTIVE: The objective of this study was to describe the profile of patients who receive DMF and to assess the effectiveness of DMF regarding relapses, disability progression, magnetic resonance imaging activity, and NEDA (No Evidence Disease Activity)-3 status in a Spanish population in a real-world setting. METHODS: We conducted a multicenter prospective study of patients who started DMF between 2014 and 2019 in Spain. Three subgroups were considered: naïve, switch to DMF because of inefficacy, and switch to DMF because of adverse effects. The effects of DMF on clinical and radiological measures were evaluated. RESULTS: Among 886 patients, 25.3% were naïve, 28.8% switched because of adverse effects, and 45.9% because of inefficacy. Median follow-up was 38.9 (interquartile range 22.6-41.8) months. Annualized relapse rates were 0.15, 0.10, and 0.10 at 12, 24, and 36 months respectively, and 77.7% of patients were relapse free at month 42. At 12, 24, and 42 months, 96.1%, 87.4%, and 79.7% of patients were progression free, respectively. The number of T1 gadolinium-enhancement (T1Gd+) lesions was 0.19, 0.14, and 0.18 at 12, 24, and 36 months. NEDA-3 status at month 42 was maintained by 49.8% of patients. Relapsing was associated with higher annualized relapse rates the year before (hazard ratio 1.34, p < 0.001) and to the inefficacy switch vs naïve group (hazard ratio 1.76, p = 0.003). A higher baseline Expanded Disability Status Scale score was associated with disability progression (hazard ratio 1.15, p = 0.003) and more T1Gd+ lesions (hazard ratio 1.07, p < 0.001) with radiological progression. A higher baseline Expanded Disability Status Scale score, a larger number of T1Gd+ lesions, and a switch because of inefficacy (vs adverse events) were all risk factors for losing NEDA-3 status. DMF was discontinued in 29.9% of patients, in 13.5% because of inefficacy. CONCLUSIONS: Our findings confirm the sustained effectiveness of DMF on the clinical and radiological activity of multiple sclerosis in a real-world setting, both in naïve patients and in those switching from other multiple sclerosis therapies.

Tolerability and safety of dimethyl fumarate in relapsing multiple sclerosis: a prospective observational multicenter study in a real-life Spanish population.

BACKGROUND: Dimethyl fumarate (DMF) tolerability and safety in multiple sclerosis (MS) has been analyzed in randomized clinical trials. Real-life studies are needed to assess possible harms of this therapy in a wider MS population. OBJECTIVE: To evaluate DMF tolerability, safety and persistence in MS in a real-world setting. METHODS: We conducted a multicenter prospective study of patients who started DMF, attended in 16 public hospitals of Spain. A specific database was elaborated to collect data on most frequent adverse events (AE). Regression models were used to analyze the effect of demographic and clinical characteristics on risk of AEs and DMF discontinuation. RESULTS: We collected data of 886 patients (2681 patients/years-exposition) with median 39.5 (IQR 23, 51.5) months on DMF exposure; 25.3% were treatment naïve and 74.7% switched to DMF from other disease-modifying therapies. DMF was discontinued in 29.9% of patients, in 13.2% due to AEs and in 13.5% to inefficacy. AEs were experienced by 71.2%, being flushing the most frequent (44.1%), 5.4% developed grade III lymphopenia, without cases of grade IV. Females showed a higher risk of flushing and gastroenteric symptoms (OR 1.49, p = 0.011; OR 1.69, p = 0.001, respectively); lymphopenia was associated with older age (OR 1.04, p < 0.001), and a higher EDSS with lymphopenia (OR 1.10, p = 0.035) and DMF withdrawal (HR 1.43, p = 0.012). No safety problems were reported. CONCLUSIONS: Our findings confirm good tolerability and safety of DMF in real-world setting and suggest that women have an increased risk of AEs and higher baseline disability involves greater risk of drug discontinuation.

[Stroke in paediatric patients with sickle-cell anaemia]. / Ictus en pacientes pediátricos con anemia falciforme.

INTRODUCTION: Sickle-cell anaemia is the severe homozygotic form of drepanocytosis, a genetic disorder that often occurs among black people and which is characterised by the production of haemoglobin S, chronic hemolytic anaemia and tissue ischaemia due to alterations in blood flow. A quarter of the patients presented neurological manifestations; 8-10% of children will have a stroke. AIM. To analyse the cases of stroke in children with sickle-cell anaemia in our centre. PATIENTS AND METHODS: We conducted a retrospective descriptive study of children with sickle-cell anaemia and stroke. RESULTS: Five patients (two Dominicans and three Guineans) with sickle-cell anaemia and stroke; one patient suffered two episodes of stroke. The mean age was 27 months. Five of the episodes were ischaemic infarctions. Stroke was the initial form of presentation of drepanocytosis on three occasions. Two of the strokes occurred within a context of pneumococcal meningitis. Four of the patients had previously reported fever. The initial clinical picture was hemiparesis in four cases. Mean haemoglobin on diagnosing the stroke was 6.5 g/dL. Transcranial ultrasound imaging revealed alterations in three patients and, in all the patients, magnetic resonance imaging revealed lesions, which were bilateral in half the cases. Following the stroke, a hypertransfusion regimen protocol was established and only one patient presented a new stroke. This same patient went on to develop moya-moya disease and was submitted to an indirect revascularisation; the patient progressed well, without presenting any new ischaemic events. CONCLUSIONS: Drepanocytosis is a disease that is emerging in our setting as a result of immigration. It should be suspected in cases of paediatric strokes associated to anaemia, above all in black children under the age of five who were not submitted to neonatal screening.

TITLE: Ictus en pacientes pediatricos con anemia falciforme.Introduccion. La anemia falciforme es la forma homocigota, grave, de drepanocitosis, un trastorno genetico, frecuente en raza negra, caracterizado por la produccion de hemoglobina S, anemia hemolitica cronica e isquemia tisular por alteracion del flujo sanguineo. Una cuarta parte de los pacientes presenta manifestaciones neurologicas; el 8-10% de los niños sufrira un ictus. Objetivo. Analizar los casos de ictus en niños con anemia falciforme en nuestro centro. Pacientes y metodos. Estudio descriptivo retrospectivo de niños con anemia falciforme e ictus. Resultados. Se recogieron cinco pacientes (dos dominicanos y tres guineanos) con anemia falciforme e ictus; un paciente sufrio dos episodios ictales. La edad media fue de 27 meses. Cinco episodios fueron infartos isquemicos. El ictus fue la forma de inicio de la drepanocitosis en tres ocasiones. Dos de los ictus ocurrieron en un contexto de meningitis neumococica. En cuatro pacientes hubo fiebre previa. La clinica inicial fue hemiparesia en cuatro casos. La hemoglobina media al diagnostico de ictus fue de 6,5 g/dL. En tres pacientes se hallaron alteraciones en la ecografia transcraneal y, en todos los pacientes, lesiones en la resonancia magnetica, que en la mitad eran bilaterales. Tras el ictus se inicio un protocolo de regimen hipertransfusional, y solo un paciente presento un nuevo ictus, que desarrollo un sindrome moya-moya y fue sometido a una revascularizacion indirecta, con buena evolucion, sin presentar nuevos eventos isquemicos posteriores. Conclusiones. La drepanocitosis es una enfermedad emergente en nuestro medio debido a la inmigracion. Debe sospecharse en ictus pediatricos asociados a anemia, sobre todo en menores de 5 años de raza negra no sometidos a cribado neonatal.