The role of the stress adaptive response in multiple sclerosis.

Lymphocyte calcium influx characteristics and its modulation by Kv1.3 and IKCa1 potassium channel inhibitors in multiple sclerosis

Progress in Multiple Sclerosis Research

Background/objectives T cells play probably a major role in the physiopathology of Multiple Sclerosis (MS). One way to study T cell responses in MS is to investigate the T cell receptor (TCR) structure in patients. This method is based on the analysis of the hypervariable region of the TCR named CDR3, responsible of the specific recognition of the antigen. To date, we know that the alterations of T cell repertoire in circulating lymphocytes are more pronounced in MS patients than in healthy controls. Moreover, several teams showed that the infiltrating T cells of the Central Nervous System (CNS) of MS patients present an oligoclonal repartition. So, it would be essential to know if correspondence exists between the alterations of the repertoire in the blood or Cerebrospinal Fluid (CSF) and in the CNS.

Objective: We investigated dopaminergic inhibition of CD4+CD25^high regulatory T lymphocytes (Treg) in relapsing-remitting multiple sclerosis (MS) patients treated with interferon (IFN)-β. Methods: MS patients were prospectively studied at baseline and during 1 year of IFN-β, and compared with healthy controls (HCs). Treg were separated by immunomagnetic sorting and the effect of dopamine (DA) on Treg was assessed in coculture experiments with homologous effector T lymphocytes (Teff). Tyrosine hydroxylase (TH), dopaminergic receptors (DR) D3 and D5, and forkhead box protein P3 (FoxP3) mRNA were assessed by real-time PCR. Circulating CD4+ T cell subsets were assessed by flow cytometry. Results: In coculture experiments, Treg inhibition of Teff proliferation was reduced by DA in HCs and completely abolished in MS patients at baseline. However, in patients after 12 months of IFN-β, Teff proliferation was impaired and DA had no more effect on Treg. In comparison to cells from HCs, Treg from MS patients at baseline had increased mRNA for DR D5 and TH (but not for DR D3). During treatment with IFN-β, both DR D5 and TH mRNA decreased down to values lower than those of cells from HCs. In comparison to HCs, MS patients had a higher frequency of circulating Treg, both at baseline and after IFN-β, while FoxP3 mRNA levels in Treg were similar in patients and HCs and did not show major changes during IFN-β. Conclusions: Dopaminergic inhibition of Treg in MS patients is suppressed during IFN-β treatment. Treg play a key role in the suppression of autoimmunity, thus the effect may have a therapeutic repercussion.

Synaptic pathology in multiple sclerosis: a role for Nogo-A signaling in astrocytes?

Multiple sclerosis, brain radiotherapy, and risk of neurotoxicity: The Mayo Clinic experience

SummaryGut 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.

Mental Disorders in Mexican Patients With Multiple Sclerosis

Multiple sclerosis (MS) is a common demyelinating disease of the central nervous system (1–86), with substantial long-term neurologic consequences (1,4,9,25,34, 52,54,55,57,60,63,65). After 10 years with MS, 50% of patients are unable to perform household and occupational responsibilities; after 15 to 20 years, 50% are unable to walk without assistance; after 25 years, 50% are unable to ambulate. The average annual cost of MS in the United States is greater than 6.8 billion dollars (1). There are three main subtypes of the disease: relapsing remitting (RR), secondary progressive (SP), and primary progressive (PP). This update reviews the current status of MS therapy (1–86). We have chosen to focus on the new and emerging immunomodulatory therapies for disease relapses and the treatments to prevent disease progression. We do not review the treatments for common MS-related sensory and motor symptoms, fatigue, or depression (35).

Multiple sclerosis (MS) is an autoimmune disease characterized by areas of inflammation, demyelination and axonal damage. The etiology of MS is multifactorial with an interaction between genetic, environmental and geographical factors. The objective of this study was to review the physiopathology and the genetic polymorphisms associated with the development and clinical course of MS. Studies carried out in populations worldwide showed that polymorphisms in the genes of the major histocompatibility complex (MHC) class II and class III have been associated with susceptibility, resistance and clinical forms of MS. Considerable attention has been focused on studies evaluating disease-modifying effects in MS that identified seven genes of probable importance such as the HLA class II, ApoE, IL-1ra, IL-1β, TNF-α, TNF-β and CCR5 genes. However, the results described in the literature about genetic biomarkers in MS are not consistent in the worldwide population. The detection of a single nucleotide polymorphism involved in the etiology and physiopathology of MS is very difficult and, it is likely that, several genetic polymorphisms are involved, each with a small contribution to the susceptibility or resistance to MS. Taken together the results show the need for continued research in genetically heterogeneous populations to identify new biomarkers associated with MS that could be used as prognostic markers or as therapeutic targets to modulate the autoimmune response in MS patients. This information may contribute to a better understanding of the physiopathology and treatment of MS, with the possibility of developing different therapeutic strategies according to the genetic profile of each individual.

Oligodendrocytes Enforce Immune Tolerance of the Uninfected Brain by Purging the Peripheral Repertoire of Autoreactive CD8+ T Cells

Multiple sclerosis: Stripping the sheath

Targeting Inflammatory Demyelinating Lesions to Sites of Wallerian Degeneration

In vitro IgG synthesis by peripheral blood lymphocytes cultured for 7 days in serum-free medium was determined by enzyme-linked immunosorbent assay. IgG synthesis by lymphocytes of multiple sclerosis (MS) patients and normal individuals in the presence of MS and non-MS brain antigens and in the absence of brain antigens was investigated. In vitro IgG synthesis by lymphocytes in the absence of any antigen was found to be similar for both groups. Non-MS brain antigens stimulated IgG synthesis by normal lymphocytes but not by MS lymphocytes. MS brain antigens were not found to stimulate IgG synthesis by lymphocytes of either group. The significance of the above-mentioned finding is discussed.

Emerging role of neuregulin-1beta1 in pathogenesis and progression of multiple sclerosis