Publications by authors named "Herena Eixarch"

23 Publications

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Selected Clostridia Strains from The Human Microbiota and their Metabolite, Butyrate, Improve Experimental Autoimmune Encephalomyelitis.

Neurotherapeutics 2021 Apr 7. Epub 2021 Apr 7.

Servei de Neurologia-Neuroimmunologia, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, Centre d'Esclerosi Múltiple de Catalunya, Pg. Vall d'Hebron 119-129, 08035, Barcelona, Spain.

Gut microbiome studies in multiple sclerosis (MS) patients are unravelling some consistent but modest patterns of gut dysbiosis. Among these, a significant decrease of Clostridia cluster IV and XIVa has been reported. In the present study, we investigated the therapeutic effect of a previously selected mixture of human gut-derived 17 Clostridia strains, which belong to Clostridia clusters IV, XIVa, and XVIII, on the clinical outcome of experimental autoimmune encephalomyelitis (EAE). The observed clinical improvement was related to lower demyelination and astrocyte reactivity as well as a tendency to lower microglia reactivity/infiltrating macrophages and axonal damage in the central nervous system (CNS), and to an enhanced immunoregulatory response of regulatory T cells in the periphery. Transcriptome studies also highlighted increased antiinflammatory responses related to interferon beta in the periphery and lower immune responses in the CNS. Since Clostridia-treated mice were found to present higher levels of the immunomodulatory short-chain fatty acid (SCFA) butyrate in the serum, we studied if this clinical effect could be reproduced by butyrate administration alone. Further EAE experiments proved its preventive but slight therapeutic impact on CNS autoimmunity. Thus, this smaller therapeutic effect highlighted that the Clostridia-induced clinical effect was not exclusively related to the SCFA and could not be reproduced by butyrate administration alone. Although it is still unknown if these Clostridia strains will have the same effect on MS patients, gut dysbiosis in MS patients could be partially rebalanced by these commensal bacteria and their immunoregulatory properties could have a beneficial effect on MS clinical course.
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http://dx.doi.org/10.1007/s13311-021-01016-7DOI Listing
April 2021

Inhibition of the BMP Signaling Pathway Ameliorated Established Clinical Symptoms of Experimental Autoimmune Encephalomyelitis.

Neurotherapeutics 2020 10;17(4):1988-2003

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, Barcelona, Spain.

Bone morphogenetic proteins (BMPs) are secreted growth factors that belong to the transforming growth factor beta superfamily. BMPs have been implicated in physiological processes, but they are also involved in many pathological conditions. Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system (CNS); however, its etiology remains elusive. Some evidence points to BMPs as important players in the pathogenesis of inflammatory and autoimmune disorders. In the present work, we studied the expression of BMP2, BMP4, BMP5, BMP6, BMP7, BMP type II receptor, and noggin in the immune system during different phases of experimental autoimmune encephalomyelitis (EAE). Major changes in the expression of BMPs took place in the initial phases of EAE. Indeed, those changes mainly affected BMP6 (whose expression was abrogated), BMP2, and BMP7 (whose expression was increased). In addition, we showed that in vivo inhibition of the BMP signaling pathway with small molecules ameliorated the already established clinical symptoms of EAE, as well as the CNS histopathological features. At the immune level, we observed an expansion of plasmacytoid dendritic cells (pDCs) in mice treated with small molecules that inhibit the BMP signaling pathway. pDCs could play an important role in promoting the expansion of antigen-specific regulatory T cells. Altogether, our data suggest a role for BMPs in early immune events that take place in myelin oligodendrocyte glycoprotein (MOG)-induced EAE. In addition, the clinical outcome of the disease was improved when the BMP signaling pathway was inhibited in mice that presented established EAE symptoms.
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http://dx.doi.org/10.1007/s13311-020-00885-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7851289PMC
October 2020

NLRP3 inflammasome as prognostic factor and therapeutic target in primary progressive multiple sclerosis patients.

Brain 2020 05;143(5):1414-1430

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Institut de Recerca Vall d'Hebron (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.

Primary progressive multiple sclerosis is a poorly understood disease entity with no specific prognostic biomarkers and scarce therapeutic options. We aimed to identify disease activity biomarkers in multiple sclerosis by performing an RNA sequencing approach in peripheral blood mononuclear cells from a discovery cohort of 44 untreated patients with multiple sclerosis belonging to different clinical forms and activity phases of the disease, and 12 healthy control subjects. A validation cohort of 58 patients with multiple sclerosis and 26 healthy control subjects was included in the study to replicate the RNA sequencing findings. The RNA sequencing revealed an interleukin 1 beta (IL1B) signature in patients with primary progressive multiple sclerosis. Subsequent immunophenotyping pointed to blood monocytes as responsible for the IL1B signature observed in this group of patients. Functional experiments at baseline measuring apoptosis-associated speck-like protein containing a CARD (ASC) speck formation showed that the NOD-leucine rich repeat and pyrin containing protein 3 (NLRP3) inflammasome was overactive in monocytes from patients with primary progressive multiple sclerosis, and canonical NLRP3 inflammasome activation with a combination of ATP plus lipopolysaccharide was associated with increased IL1B production in this group of patients. Primary progressive multiple sclerosis patients with high IL1B gene expression levels in peripheral blood mononuclear cells progressed significantly faster compared to patients with low IL1B levels based on the time to reach an EDSS of 6.0 and the Multiple Sclerosis Severity Score. In agreement with peripheral blood findings, both NLRP3 and IL1B expression in brain tissue from patients with primary progressive multiple sclerosis was mainly restricted to cells of myeloid lineage. Treatment of mice with a specific NLRP3 inflammasome inhibitor attenuated established experimental autoimmune encephalomyelitis disease severity and improved CNS histopathology. NLRP3 inflammasome-specific inhibition was also effective in reducing axonal damage in a model of lipopolysaccharide-neuroinflammation using organotypic cerebellar cultures. Altogether, these results point to a role of IL1B and the NLRP3 inflammasome as prognostic biomarker and potential therapeutic target, respectively, in patients with primary progressive multiple sclerosis.
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http://dx.doi.org/10.1093/brain/awaa084DOI Listing
May 2020

A Commercial Probiotic Induces Tolerogenic and Reduces Pathogenic Responses in Experimental Autoimmune Encephalomyelitis.

Cells 2020 04 7;9(4). Epub 2020 Apr 7.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain.

Previous studies in experimental autoimmune encephalomyelitis (EAE) models have shown that some probiotic bacteria beneficially impact the development of this experimental disease. Here, we tested the therapeutic effect of two commercial multispecies probiotics-Lactibiane iki and Vivomixx-on the clinical outcome of established EAE. Lactibiane iki improves EAE clinical outcome in a dose-dependent manner and decreases central nervous system (CNS) demyelination and inflammation. This clinical improvement is related to the inhibition of pro-inflammatory and the stimulation of immunoregulatory mechanisms in the periphery. Moreover, both probiotics modulate the number and phenotype of dendritic cells (DCs). Specifically, Lactibiane iki promotes an immature, tolerogenic phenotype of DCs that can directly induce immune tolerance in the periphery, while Vivomixx decreases the percentage of DCs expressing co-stimulatory molecules. Finally, gut microbiome analysis reveals an altered microbiome composition related to clinical condition and disease progression. This is the first preclinical assay that demonstrates that a commercial probiotic performs a beneficial and dose-dependent effect in EAE mice and one of the few that demonstrates a therapeutic effect once the experimental disease is established. Because this probiotic is already available for clinical trials, further studies are being planned to explore its therapeutic potential in multiple sclerosis patients.
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http://dx.doi.org/10.3390/cells9040906DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7226819PMC
April 2020

Targeted resequencing reveals rare variants enrichment in multiple sclerosis susceptibility genes.

Hum Mutat 2020 07 1;41(7):1308-1320. Epub 2020 Apr 1.

Servei de Neurologia-Neuroimmunologia, Center d'Esclerosi Múltiple de Catalunya (Cemcat), Institut de Recerca Vall d'Hebron (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.

Although genome-wide association studies have identified a number of common variants associated with multiple sclerosis (MS) susceptibility, little is known about the relevance of rare variants. Here, we aimed to explore the role of rare variants in 14 MS risk genes (FCRL1, RGS1, TIMMDC1, HHEX, CXCR5, LTBR, TSFM, GALC, TRAF3, STAT3, TNFSF14, IFI30, CD40, and CYP24A1) by targeted resequencing in an Iberian population of 524 MS cases and 546 healthy controls. Four rare variants-enriched regions within CYP24A1, FCRL1, RGS1, and TRAF3 were identified as significantly associated with MS. Functional studies revealed significantly decreased regulator of G protein signaling 1 (RGS1) gene expression levels in peripheral blood mononuclear cells from MS patients with RGS1 rare variants compared to noncarriers, whereas no significant differences in gene expression were observed for CYP24A1, FCRL1, and TRAF3 between rare variants carriers and noncarriers. Immunophenotyping showed significant decrease in RGS1 expression in peripheral blood B lymphocytes from MS patients with RGS1 rare variants relative to noncarriers. Lastly, peripheral blood mononuclear cell from MS patients carrying RGS1 rare variants showed significantly lower induction of RGS1 gene expression by interferon-β compared to MS patients lacking RGS1 variants. The presence of rare variants in RGS1 reinforce the ideas of high genetic heterogeneity and a role of rare variants in MS pathogenesis.
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http://dx.doi.org/10.1002/humu.24016DOI Listing
July 2020

A New Risk Variant for Multiple Sclerosis at 11q23.3 Is Associated with Expansion of Circulating Regulatory T Cells.

J Clin Med 2020 Feb 26;9(3). Epub 2020 Feb 26.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat). Institut de Recerca Vall d'Hebron (VHIR). Hospital Universitari Vall d'Hebron. Universitat Autònoma de Barcelona, 08035 Barcelona, Spain.

Genome-wide association studies and meta-analysis have contributed to the identification of more than 200 associated with multiple sclerosis (MS). However, a proportion of MS heritability remains unknown. We aimed to uncover new genetic variants associated with MS and determine their functional effects. For this, we resequenced the exons and regulatory sequences of 14 MS risk genes in a cohort of MS patients and healthy individuals ( = 1,070) and attempted to validate a selection of signals through genotyping in an independent cohort ( = 5,138). We identified three new MS-associated variants at C-X-C motif chemokine receptor 5 (, Ts translation elongation factor, mitochondrial ( and cytochrome P450 family 24 subfamily A member 1 (. Rs10892307 resulted in a new signal at the region that explains one of the associations with MS within the . This polymorphism and three others in high linkage disequilibrium mapped within regulatory regions. Of them, rs11602393 showed allele-dependent enhancer activity in the forward orientation as determined by luciferase reporter assays. Immunophenotyping using peripheral blood mononuclear cells from MS patients associated the minor allele of rs10892307 with increased percentage of regulatory T cells expressing CXCR5. This work reports a new signal for the MS risk and points to rs11602393 as the causal variant. The expansion of CXCR5+ circulating regulatory T cells induced by this variant could cause its MS association.
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http://dx.doi.org/10.3390/jcm9030625DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7141122PMC
February 2020

Expression of Bone Morphogenetic Proteins in Multiple Sclerosis Lesions.

Am J Pathol 2019 03 13;189(3):665-676. Epub 2018 Dec 13.

Neurology-Neuroimmunology Department, Multiple Sclerosis Centre of Catalonia (Cemcat), Vall d'Hebron Research Institute (VHIR), Vall d'Hebron University Hospital, Barcelona, Spain; Autonomous University of Barcelona, Barcelona, Spain. Electronic address:

Bone morphogenetic proteins (BMPs) are secreted proteins that belong to the transforming growth factor-β superfamily. In the adult brain, they modulate neurogenesis, favor astrogliogenesis, and inhibit oligodendrogenesis. Because BMPs may be involved in the failure of remyelination in multiple sclerosis (MS), we characterized the expression of BMP-2, BMP-4, BMP-5, and BMP-7; BMP type II receptor (BMPRII); and phosphorylated SMAD (pSMAD) 1/5/8 in lesions of MS and other demyelinating diseases. A total of 42 MS lesions, 12 acute ischemic lesions, 8 progressive multifocal leukoencephalopathy lesions, and 10 central nervous system areas from four nonneuropathological patients were included. Lesions were histologically classified according to the inflammatory activity. The expression of BMP-2, BMP-4, BMP-5, BMP-7, BMPRII, and pSMAD1/5/8 was quantified by immunostaining, and colocalization studies were performed. In MS lesions, astrocytes, microglia/macrophages, and neurons expressed BMP-2, BMP-4, BMP-5, and BMP-7; BMPRII; and pSMAD1/5/8. Oligodendrocytes expressed BMP-2 and BMP-7 and pSMAD1/5/8. The percentage of cells that expressed BMPs, BMPRII, and pSMAD1/5/8 correlated with the inflammatory activity of MS lesions, and changes in the percentage of positive cells were more relevant in MS than in other white matter-damaging diseases. These data indicate that BMPs are increased in active MS lesions, suggesting a possible role in MS pathogenesis.
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http://dx.doi.org/10.1016/j.ajpath.2018.11.007DOI Listing
March 2019

Multi-centre validation of a flow cytometry method to identify optimal responders to interferon-beta in multiple sclerosis.

Clin Chim Acta 2019 Jan 5;488:135-142. Epub 2018 Nov 5.

Immunology Dpt. and Biostatistic Unit, Hospital Universitario Ramón y Cajal, IRYCIS, Ctra. de Colmenar Viejo km 9.100, 28034 Madrid, Spain; Red Española de Esclerosis Múltiple (REEM), Spain. Electronic address:

Background And Objectives: Percentages of blood CD19+CD5+ B cells and CD8+perforin+ T lymphocytes can predict response to Interferon (IFN)-beta treatment in relapsing-remitting multiple sclerosis (RRMS) patients. We aimed to standardize their detection in a multicenter study, prior to their implementation in clinical practice.

Methods: Fourteen hospitals participated in the study. A reference centre was established for comparison studies. Peripheral blood cells of 105 untreated RRMS patients were studied. Every sample was analyzed in duplicate in the participating centre and in the reference one by flow cytometry. When needed, participating centres corrected fluorescence compensations and negative cut-off position following reference centre suggestions. Concordance between results obtained by participating centres and by reference one was evaluated by intraclass correlation coefficients (ICC) and Spearman correlation test. Centre performance was measured by using z-scores values.

Results: After results review and corrective actions implementation, overall ICC was 0.86 (CI: 0.81-0.91) for CD19+CD5+ B cell and 0.89 (CI: 0.85-0.93) for CD8+ perforin+ T cell quantification; Spearman r was 0.92 (0.89-0.95; p <0.0001) and 0.92 (0.88-0.95; p <0.0001) respectively. All centres obtained z-scores≤0.5 for both biomarkers.

Conclusion: Homogenous percentages of CD19+CD5+ B cells and CD8 perforin+ T lymphocytes can be obtained if suitable compensation values and negative cut-off are pre-established.
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http://dx.doi.org/10.1016/j.cca.2018.11.008DOI Listing
January 2019

GDP-l-fucose synthase is a CD4 T cell-specific autoantigen in DRB3*02:02 patients with multiple sclerosis.

Sci Transl Med 2018 10;10(462)

Neuroimmunology and MS Research (nims), Department of Neurology, University Hospital Zurich, Frauenklinikstrasse 26, 8091 Zürich, Switzerland.

Multiple sclerosis is an immune-mediated autoimmune disease of the central nervous system that develops in genetically susceptible individuals and likely requires environmental triggers. The autoantigens and molecular mimics triggering the autoimmune response in multiple sclerosis remain incompletely understood. By using a brain-infiltrating CD4 T cell clone that is clonally expanded in multiple sclerosis brain lesions and a systematic approach for the identification of its target antigens, positional scanning peptide libraries in combination with biometrical analysis, we have identified guanosine diphosphate (GDP)-l-fucose synthase as an autoantigen that is recognized by cerebrospinal fluid-infiltrating CD4 T cells from HLA-DRB3*-positive patients. Significant associations were found between reactivity to GDP-l-fucose synthase peptides and DRB3*02:02 expression, along with reactivity against an immunodominant myelin basic protein peptide. These results, coupled with the cross-recognition of homologous peptides from gut microbiota, suggest a possible role of this antigen as an inducer or driver of pathogenic autoimmune responses in multiple sclerosis.
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http://dx.doi.org/10.1126/scitranslmed.aat4301DOI Listing
October 2018

Combined therapies to treat complex diseases: The role of the gut microbiota in multiple sclerosis.

Autoimmun Rev 2018 Feb 28;17(2):165-174. Epub 2017 Nov 28.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193, Bellaterra, Cerdanyola del Vallès, Spain. Electronic address:

The commensal microbiota has emerged as an environmental risk factor for multiple sclerosis (MS). Studies in experimental autoimmune encephalomyelitis (EAE) models have shown that the commensal microbiota is an essential player in triggering autoimmune demyelination. Likewise, the commensal microbiota modulates the host immune system, alters the integrity and function of biological barriers and has a direct effect on several types of central nervous system (CNS)-resident cells. Moreover, a characteristic gut dysbiosis has been recognized as a consistent feature during the clinical course of MS, and the MS-related microbiota is gradually being elucidated. This review highlights animal studies in which commensal microbiota modulation was tested in EAE, as well as the mechanisms of action and influence of the commensal microbiota not only in the local milieu but also in the innate and adaptive immune system and the CNS. Regarding human research, this review focuses on studies that show how the commensal microbiota might act as a pathogenic environmental risk factor by directing immune responses towards characteristic pathogenic profiles of MS. We speculate how specific microbiome signatures could be obtained and used as potential pathogenic events and biomarkers for the clinical course of MS. Finally, we review recently published and ongoing clinical trials in MS patients regarding the immunomodulatory properties exerted by some microorganisms. Because MS is a complex disease with a large variety of associated environmental risk factors, we suggest that current treatments combined with strategies that modulate the commensal microbiota would constitute a broader immunotherapeutic approach and improve the clinical outcome for MS patients.
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http://dx.doi.org/10.1016/j.autrev.2017.11.019DOI Listing
February 2018

Clinical and Histopathological Amelioration of Experimental Autoimmune Encephalomyelitis by AAV Vectors Expressing a Soluble Interleukin-23 Receptor.

Neurotherapeutics 2017 Oct;14(4):1095-1106

Institut de Neurociències (INc), Departament Bioquímica i Biologia Molecular, Universitat Autònoma Barcelona, Bellaterra, Spain.

The role of the T helper (Th)17 pathway has been clearly demonstrated in the onset and progression of autoimmune diseases, where interleukin (IL)-23 is a key molecule in maintaining the response mediated by Th17 cells. As a consequence, recent strategies based on blocking the interaction between IL-23 and its receptor (IL-23R), for example the anti-p19 antibody tildrakizumab, have been developed to regulate the Th17 pathway from the initial stages of the disease. Here, a soluble (s)IL-23R cDNA was cloned in expression plasmids and viral vectors. The clinical efficacy of sIL-23R was evaluated in myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis mice intravenously injected with a single dose of adeno-associated virus AAV8-sIL-23R vectors. Cytokine secretion was determined by multiplex assay, while histopathological analysis of the central nervous system was performed to study demyelination, inflammatory infiltration, and microglia and astroglia activation. We observed that administration of adeno-associated vector 8 encoding sIL-23R was associated with a significant disease improvement, including delay in the onset of the clinical signs; slower progress of the disease; interference with IL-23-mediated signal transducer and activator of transcription response by inhibiting of signal transducer and activator of transcription 3 phosphorylation; reduced demyelination and infiltration in the central nervous system; and lower astrocyte and microglia activation. Our results suggest that the use of vectors carrying sIL-23R to block the IL-23/IL-23R interaction may be a new therapeutic strategy for the treatment of multiple sclerosis.
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http://dx.doi.org/10.1007/s13311-017-0545-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5722756PMC
October 2017

Bone morphogenetic proteins in multiple sclerosis: Role in neuroinflammation.

Brain Behav Immun 2018 02 27;68:1-10. Epub 2017 Feb 27.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola del Vallès, Spain. Electronic address:

Bone morphogenetic proteins (BMPs) are growth factors that represent the largest subgroup of signalling ligands of the transforming growth factor beta (TGF-β) superfamily. Their participation in the proliferation, survival and cell fate of several cell types and their involvement in many pathological conditions are now well known. BMP expression is altered in multiple sclerosis (MS) patients, suggesting that BMPs have a role in the pathogenesis of this disease. MS is a demyelinating and neurodegenerative autoimmune disorder of the central nervous system (CNS). MS is a complex pathological condition in which genetic, epigenetic and environmental factors converge, although its aetiology remains elusive. Multifunctional molecules, such as BMPs, are extremely interesting in the field of MS because they are involved in the regulation of several adult tissues, including the CNS and the immune system. In this review, we discuss the extensive data available regarding the role of BMP signalling in neuronal progenitor/stem cell fate and focus on the participation and expression of BMPs in CNS demyelination. Additionally, we provide an overview of the involvement of BMPs as modulators of the immune system, as this subject has not been thoroughly explored even though it is of great interest in autoimmune disorders. Moreover, we describe the data on BMP signalling in autoimmunity and inflammatory diseases, including MS and its experimental models. Thus, we aim to provide an integrated view of the putative role of BMPs in MS pathogenesis and to open the field for the further development of alternative therapeutic strategies for MS patients.
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http://dx.doi.org/10.1016/j.bbi.2017.02.019DOI Listing
February 2018

Myeloid-derived suppressor cells expressing a self-antigen ameliorate experimental autoimmune encephalomyelitis.

Exp Neurol 2016 Dec 28;286:50-60. Epub 2016 Sep 28.

Gene and Cell Therapy Laboratory, Vall d'Hebron Institut de Recerca (VHIR), Passeig Vall d'Hebron 119-129, Barcelona 08035, Spain; Universitat Autònoma de Barcelona, 08193, Bellaterra, Cerdanyola del Vallès, Spain. Electronic address:

Previous work by our group showed that transferring bone marrow cells transduced with a self-antigen induced immune tolerance and ameliorated experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS). We also found that following retroviral transduction of murine bone marrow (BM) cells, the majority of cells generated and transduced were myeloid-derived suppressor cells (MDSCs). Here, we aimed to determine whether purified antigen-expressing MDSCs have similar therapeutic effects than those of unfractionated BM, and to investigate their potential mechanisms. We performed phenotypic and functional analyses in these cells using the same animal model, and we used purified antigen-expressing MDSCs in preventive and therapeutic approaches. These cells exerted therapeutic effects similar to those of BM cells, which depended upon self-antigen expression. The majority of monocytic (M)-MDSCs expressed the immunosuppressive molecule programmed death ligand-1 (PD-L1), CD80, CD86 and MHC class II molecules. Additionally, the animals infused with antigen-expressing cells exhibited lower percentages of activated T cells and higher percentages of B cells with a regulatory phenotype (B220CD1d CD5) in the spleen than their respective controls. MDSCs expressing self-antigens, alloantigens or therapeutic transgenes are tolerogenic and can be exploited therapeutically in autoimmune diseases, transplantation and in gene therapy, respectively.
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http://dx.doi.org/10.1016/j.expneurol.2016.09.012DOI Listing
December 2016

Semaphorin 7A as a Potential Therapeutic Target for Multiple Sclerosis.

Mol Neurobiol 2017 08 6;54(6):4820-4831. Epub 2016 Oct 6.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, Ps. Vall d'Hebron, 119-129, 08035, Barcelona, Spain.

Semaphorin 7A (sema7A) is classified as an immune semaphorin with dual functions in the immune system and in the central nervous system (CNS). These molecules are of interest due to their potential role in multiple sclerosis (MS), which is a chronic demyelinating and neurodegenerative disease of autoimmune origin. In this study, we elucidated the role of sema7A in neuroinflammation using both in vitro and in vivo experimental models. In an in vitro model of neuroinflammation, using cerebellar organotypic slice cultures, we observed that challenge with lipopolysaccharide (LPS) endotoxin did not affect demyelination or cell death in sema7A-deficient cultures compared to wild-type cultures. Moreover, the in vivo outcome of experimental autoimmune encephalomyelitis (EAE) in sema7A-deficient mice was altered in an antigen- and adjuvant-dose-dependent manner, while no differences were observed in the wild-type counterparts. Altogether, these results indicate that sema7A is involved in peripheral immunity and CNS inflammation in MS pathogenesis. Indeed, these data suggest that sema7A might be a potential therapeutic target to treat MS and autoimmune conditions.
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http://dx.doi.org/10.1007/s12035-016-0154-2DOI Listing
August 2017

Neurofilament light chain level is a weak risk factor for the development of MS.

Neurology 2016 Sep 12;87(11):1076-84. Epub 2016 Aug 12.

From Servei de Neurologia-Neuroimmunologia (G.A., C.E., H.E., J.S.-G., E.S., M.C., J.R., C.N., C.T., J.C., A.V.-J., I.G., M.J.A., X.M., M.T.), Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, Barcelona; Universitat Autònoma de Barcelona (G.A., C.E., H.E., J.S.-G., E.S., M.C., J.R., C.N., C.T., J.C., A.V.-J., I.G., X.M., M.T.), Bellaterra; Departments of Neurology and Immunology (L.M.V., J.C.A.-C., C.P.), Multiple Sclerosis Unit, Hospital Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain; Department of Neurology (J.K., L.K.), University Hospital Basel; Neurocentre of Southern Switzerland (G.D.), Ospedale Civico, Lugano, Switzerland; and Magnetic Resonance Unit (IDI) (D.P., C.A., A.R.), Hospital Universitari Vall d'Hebron, Barcelona, Spain.

Objective: To determine the prognostic value of selected biomarkers in clinically isolated syndromes (CIS) for conversion to multiple sclerosis (MS) and disability accrual.

Methods: Data were acquired from 2 CIS cohorts. The screening phase evaluated patients developing clinically definite MS (CIS-CDMS) and patients who remained as CIS during a 2-year minimum follow-up (CIS-CIS). We determined levels of neurofascin, semaphorin 3A, fetuin A, glial fibrillary acidic protein, and neurofilament light (NfL) and heavy chains in CSF (estimated mean [95% confidence interval; CI]). We evaluated associations between biomarker levels, conversion, disability, and magnetic resonance parameters. In the replication phase, we determined NfL levels (n = 155) using a 900 ng/L cutoff. Primary endpoints in uni- and multivariate analyses were CDMS and 2010 McDonald MS.

Results: The only biomarker showing significant differences in the screening was NfL (CIS-CDMS 1,553.1 [1,208.7-1,897.5] ng/L and CIS-CIS 499.0 [168.8-829.2] ng/L, p < 0.0001). The strongest associations were with brain parenchymal fraction change (rs = -0.892) and percentage brain volume change (rs = -0.842) at 5 years. NfL did not correlate with disability. In the replication phase, more NfL-positive patients, according to the cutoff, evolved to MS. Every 100-ng/L increase in NfL predicted CDMS (hazard ratio [HR] = 1.009, 95% CI 1.005-1.014) and McDonald MS (HR = 1.009, 95% CI 1.005-1.013), remaining significant for CDMS in the multivariate analysis (adjusted HR = 1.005, 95% CI 1.000-1.011). This risk was lower than the presence of oligoclonal bands or T2 lesions.

Conclusions: NfL is a weak independent risk factor for MS. Its role as an axonal damage biomarker may be more relevant as suggested by its association with medium-term brain volume changes.
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http://dx.doi.org/10.1212/WNL.0000000000003085DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5027802PMC
September 2016

Differential expression of sema3A and sema7A in a murine model of multiple sclerosis: Implications for a therapeutic design.

Clin Immunol 2016 Feb 10;163:22-33. Epub 2015 Dec 10.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya, Vall d'Hebron Institut de Recerca, Hospital UniversitariVall d'Hebron, 08035 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193, Bellaterra, Cerdanyola del Vallès, Spain. Electronic address:

We characterised the expression of semaphorin (sema)3A, sema7A and their receptors in the immune and the central nervous system (CNS) at different stages of experimental autoimmune encephalomyelitis (EAE). We also studied their expression in neonatal and adult oligodendrocyte progenitor cell (OPC) and in mature oligodendrocyte cultures. Our results show that sema3A is increased in the CNS and decreased in the immune system upon EAE induction. However, sema7A expression is increased in both the CNS and the immune system during EAE. We also detected sema3A, sema7A and their receptors in neonatal and adult OPCs and in mature oligodendrocytes. These data suggest that sema3A and sema7A are involved in the pathogenesis of EAE, in the modulation of the immune response and in the neurodegeneration that take place in the CNS. Sema7A may represent an intriguing potential therapeutic target for the treatment of both the neurodegenerative and immune-mediated disease processes in MS.
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http://dx.doi.org/10.1016/j.clim.2015.12.005DOI Listing
February 2016

Hsp70 regulates immune response in experimental autoimmune encephalomyelitis.

PLoS One 2014 25;9(8):e105737. Epub 2014 Aug 25.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Barcelona, Spain; Universitat Autònoma de Barcelona, Bellaterra, Cerdanyola del Vallès, Barcelona, Spain.

Heat shock protein (Hsp)70 is one of the most important stress-inducible proteins. Intracellular Hsp70 not only mediates chaperone-cytoprotective functions but can also block multiple steps in the apoptosis pathway. In addition, Hsp70 is actively released into the extracellular milieu, thereby promoting innate and adaptive immune responses. Thus, Hsp70 may be a critical molecule in multiple sclerosis (MS) pathogenesis and a potential target in this disease due to its immunological and cytoprotective functions. To investigate the role of Hsp70 in MS pathogenesis, we examined its immune and cytoprotective roles using both in vitro and in vivo experimental procedures. We found that Hsp70.1-deficient mice were more resistant to developing experimental autoimmune encephalomyelitis (EAE) compared with their wild-type (WT) littermates, suggesting that Hsp70.1 plays a critical role in promoting an effective myelin oligodendrocyte glycoprotein (MOG)-specific T cell response. Conversely, Hsp70.1-deficient mice that developed EAE showed an increased level of autoreactive T cells to achieve the same production of cytokines compared with the WT mice. Although a neuroprotective role of HSP70 has been suggested, Hsp70.1-deficient mice that developed EAE did not exhibit increased demyelination compared with the control mice. Accordingly, Hsp70 deficiency did not influence the vulnerability to apoptosis of oligodendrocyte precursor cells (OPCs) in culture. Thus, the immunological role of Hsp70 may be relevant in EAE, and specific therapies down-regulating Hsp70 expression may be a promising approach to reduce the early autoimmune response in MS patients.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0105737PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4143280PMC
November 2015

Regulatory lymphocytes are key factors in MHC-independent resistance to EAE.

J Immunol Res 2014 27;2014:156380. Epub 2014 Apr 27.

Multiple Sclerosis Unit, Immunology and Neurology Departments, Hospital Universitario Ramón y Cajal, IRYCIS, Carretera de Colmenar Km 9.100, 28034 Madrid, Spain ; Red Española de Esclerosis Múltiple (REEM), RETICS, Fondo de Investigación Sanitaria, Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain.

Background And Objectives: Resistant and susceptible mouse strains to experimental autoimmune encephalomyelitis (EAE), an inducible demyelinating experimental disease serving as animal model for multiple sclerosis, have been described. We aimed to explore MHC-independent mechanisms inducing resistance to EAE.

Methods: For EAE induction, female C57BL/6 (susceptible strain) and CD1 (resistant outbred strain showing heterogeneous MHC antigens) mice were immunized with the 35-55 peptide of myelin oligodendrocyte glycoprotein (MOG35-55). We studied T cell proliferation, regulatory and effector cell subpopulations, intracellular and serum cytokine patterns, and titers of anti-MOG serum antibodies.

Results: Upon immunization with MOG35-55, T lymphocytes from susceptible mice but not that of resistant strain were capable of proliferating when stimulated with MOG35-55. Accordingly, resistant mice experienced a rise in regulatory B cells (P=0.001) and, to a lower extent, in regulatory T cells (P=0.02) compared with C57BL/6 susceptible mice. As a consequence, MOG35-55-immunized C57BL/6 mice showed higher percentages of CD4+ T cells producing both IFN-gamma (P=0.02) and IL-17 (P=0.009) and higher serum levels of IL-17 (P=0.04) than resistant mice.

Conclusions: Expansion of regulatory B and T cells contributes to the induction of resistance to EAE by an MHC-independent mechanism.
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http://dx.doi.org/10.1155/2014/156380DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4020375PMC
December 2014

Inhibition of delta-like ligand 4 decreases Th1/Th17 response in a mouse model of multiple sclerosis.

Neurosci Lett 2013 Apr 1;541:161-6. Epub 2013 Mar 1.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (CEM-Cat), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Ps. Vall d'Hebron, 119-129, 08035 Barcelona, Spain.

Notch is a family of receptors involved in the differentiation of several tissues, including the central nervous system and the immune system. One of the Notch ligands, delta-like 4 (Dll4), has been implicated in the differentiation of Th1 cells and the development of Th17 responses, which are involved in the pathogenesis of experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis. Our results show that a single administration of an anti-Dll4 antibody is not enough to avoid the development of EAE or to ameliorate the already established clinical signs, despite the treatment reduces the proliferative T cell responses and decreases Th1/Th17 immune responses.
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http://dx.doi.org/10.1016/j.neulet.2013.02.038DOI Listing
April 2013

Semaphorins 3A and 7A: potential immune and neuroregenerative targets in multiple sclerosis.

Trends Mol Med 2013 Mar 16;19(3):157-64. Epub 2013 Feb 16.

Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Ps. Vall d'Hebron, 119-129, 08035 Barcelona, Spain.

Semaphorins have been classically defined as axonal signalling cues involved in central nervous system (CNS) development, but in adults these molecules are expressed in distinct tissues and exert various functions under several physiological and pathological contexts. Semaphorins capable of modulating the immune system are particularly relevant in autoimmune diseases, especially multiple sclerosis (MS), which is a demyelinating, neurodegenerative disease. In this article, we compile recent insights into the specific roles of semaphorin (sema)3A and sema7A to clarify the details of their possible participation in the inflammatory and neurodegenerative phases of MS.
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http://dx.doi.org/10.1016/j.molmed.2013.01.003DOI Listing
March 2013

Myeloid-derived suppressor cells are generated during retroviral transduction of murine bone marrow.

Cell Transplant 2014 Jan 27;23(1):73-85. Epub 2012 Nov 27.

Gene and Cell Therapy Laboratory, Vall d'Hebron Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain.

Previous work by our group showed that transferring bone marrow cells transduced with an autoantigen into nonmyeloablated mice with experimental autoimmune encephalomyelitis induced immune tolerance and improved symptoms of the disease. Because this effect occurred in the absence of molecular chimerism, we hypothesized that the cells responsible did not have repopulating ability and that they were not mediating central but peripheral tolerance mechanisms. In the present study, we analyzed the immunophenotype of the cells that are generated in the transduction cultures and we evaluated the immunosuppressive activity of the main cell subpopulations produced. We show that both granulocytic (CD11b(+) Gr-1(hi)) and monocytic (CD11b(+) Gr-1(lo)) myeloid-derived suppressor cells (G- and M-MDSCs, respectively) are generated during standard 4-day γ-retroviral transduction cultures (representing about 25% and 40% of the total cell output, respectively) and that the effectively transduced cells largely consist of these two cell types. A third cell population representing about 15% of the transduced cells did not express CD45 or hematopoietic lineage markers and expressed mesenchymal stromal cell markers. Transduced total bone marrow cells and sorted M-MDSCs expressed arginase and inducible nitric oxide synthase activities, produced reactive oxygen species, and inhibited antigen-induced T-cell proliferation in vitro. Transgene-expressing MDSCs could be exploited therapeutically to induce tolerance in autoimmune diseases and in gene therapy protocols.
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http://dx.doi.org/10.3727/096368912X658971DOI Listing
January 2014

Transgene expression levels determine the immunogenicity of transduced hematopoietic grafts in partially myeloablated mice.

Mol Ther 2009 Nov 25;17(11):1904-9. Epub 2009 Aug 25.

Banc de Sang i Teixits, Institut de Recerca Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.

We investigated whether transgene expression levels influence the immunogenicity of transduced hematopoietic grafts upon transplantation into partially myeloablated mice. To this aim, bone marrow cells (BMCs) transduced with retroviral vectors driving green fluorescent protein (GFP) expression either at high (high-EGFP) or low levels (low-EGFP) were transplanted into congenic recipients conditioned with sublethal doses of total body irradiation (TBI) or busulfan. Virtually all recipients showed evidence of donor engraftment 4 weeks after transplantation. However, as opposed to recipients receiving low-EGFP transduced grafts, the risk of rejecting the EGFP(+) cells by 30 days after transplantation was significantly higher in mice conditioned with busulfan and receiving high-EGFP transduced grafts. Anti-EGFP cellular immune responses were demonstrated in high-EGFP-treated mice conditioned with busulfan by interferon-gamma (IFN-gamma), enzyme-linked immunospot assay (ELISPOT), and cytotoxic T lymphocyte (CTL) assays, in contrast to that observed in mice transplanted with low-EGFP BMC. These results show for the first time that transgene expression levels can be critical for the immunogenicity of gene-modified hematopoietic grafts, especially in immunocompetent or in partially immunosuppressed recipients. These results have profound implications in vector choice and in the design of gene therapy (GT) protocols.
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http://dx.doi.org/10.1038/mt.2009.198DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835042PMC
November 2009

Tolerance induction in experimental autoimmune encephalomyelitis using non-myeloablative hematopoietic gene therapy with autoantigen.

Mol Ther 2009 May 10;17(5):897-905. Epub 2009 Mar 10.

Centre de Teixits i Teràpia Cel.lular, Banc de Sang i Teixits, Institut de Recerca Hospital Universitari Vall d'Hebron, Barcelona, Spain.

Experimental autoimmune encephalomyelitis (EAE) constitutes a paradigm of antigen (Ag)-specific T cell driven autoimmune diseases. In this study, we transferred bone marrow cells (BMCs) expressing an autoantigen (autoAg), the peptide 40-55 of the myelin oligodendrocytic glycoprotein (MOG(40-55)), to induce preventive and therapeutic immune tolerance in a murine EAE model. Transfer of BMC expressing MOG(40-55) (IiMOG-BMC) into partially myeloablated mice resulted in molecular chimerism and in robust protection from the experimental disease. In addition, in mice with established EAE, transfer of transduced BMC with or without partial myeloablation reduced the clinical and histopathological severity of the disease. In these experiments, improvement was observed even in the absence of engraftment of the transduced hematopoietic cells, probably rejected due to the previous immunization with the autoAg. Splenocytes from mice transplanted with IiMOG-BMC produced significantly higher amounts of interleukin (IL)-5 and IL-10 upon autoAg challenge than those of control animals, suggesting the participation of regulatory cells. Altogether, these results suggest that different tolerogenic mechanisms may be mediating the preventive and the therapeutic effects. In conclusion, this study demonstrates that a cell therapy using BMC expressing an autoAg can induce Ag-specific tolerance and ameliorate established EAE even in a nonmyeloablative setting.
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http://dx.doi.org/10.1038/mt.2009.42DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835141PMC
May 2009