Analysis of the Distribution of Regulatory B Cells in Blood of Multiple Sclerosis Patients
Condition: Multiple Sclerosis; Systemic Sclerosis
MeSH terms: Multiple Sclerosis; Scleroderma, Systemic; Scleroderma, Diffuse; Sclerosis
Study type: Observational

Summary: 
      New therapeutic approaches of MS are emerging, targeting different actors of the immune
      system. Some of them target a specific population of white blood cells: B lymphocytes
      composed of different subpopulations. The subsets of B cells express different functional
      properties that control the immune response, but these regulation mechanisms have yet to be
      clearly described. Some subpopulations could amplify inflammation through IL-6 production for
      example, whereas some ones contribute to its regulation through the production of IL-10.
      Using samples collected in a large cohort of individuals with risk of MS and treatment-naive
      patients in the early onset of the disease, the investigators aim to develop a 2 year
      follow-up study of the different blood B cells subset distribution and their functional
      properties in terms of pro- and anti-inflammatory cytokine production in MS. This approach
      can identify new biomarkers for monitoring of MS patients and lead to better define the
      indication use of depletive B cell drugs and not to counteract the regulatory action of these
      cells.
    

Detailed description: 
      Multiple sclerosis (MS) is a progressive immuno-inflammatory and degenerative disease of the
      central nervous system (CNS) and represents the second most common cause of disability in
      young people. The pathophysiologic mechanisms involved are complex and effective therapeutic
      strategies have yet to be defined. Moreover it's today evident that treatment approaches have
      to be performed in a personalized point of view. In this context, biomarkers evaluating the
      course of the disease but also predicting efficacy of therapy are particularly needed in MS.

      Recent data underlines the direct role of B-cells in MS. Such comprehensive data have led to
      new therapeutic strategies using biotherapies in order to deplete, or modulate, the functions
      of peripheral B cells. Such approaches have led to contradictory results of efficacy. Today,
      it remains unclear whether B-cells exert diminished regulatory effects or instead potentiate
      the pathogenic response of T-cells. Such dual properties may depend on the release of
      inhibitory (e.g. interleukin-10) or pro-inflammatory cytokines (e.g. interleukin-6) and/or
      direct interactions with other cells, especially T cells.

      The investigators aim to longitudinally evaluate quantitative and functional changes in
      peripheral blood B-cell subsets (1) at the initiation phases of MS, i.e. radiological
      isolated syndrome (RIS) and clinically isolated syndrome (CIS) (2) during progression of MS
      and (3) between the two clinical forms of MS in naïve treatment patient: Relapsing-Remittent
      MS (RRMS) and Primary Progressive MS (PPMS). B-cell subsets are defined by a combination of
      membrane markers and enumerated at different time points (inclusion (before treatment) and at
      3, 6, 12, 24 months of treatment initiation) in a whole blood flow cytometric (FCM) analysis.
      The absolute counts and relative proportions of transitional, naïve, memory, and marginal
      zone-like B-cell subsets are being followed up prospectively in patients with a
      radiologically isolated syndrome (RIS, n= 20), with clinically isolated syndrome (CIS, n=
      20), in MS patients with relapsing remitting form (RRMS, n = 20) and in MS patients with
      primary progressive evolution of the disease (PPMS, n = 20). Control samples are being
      collected from patients affected by other inflammatory diseases with neurological symptoms
      (Devic syndrome, Neurobehcet, neurosarcoidosis n = 20) or without neurological symptoms
      (systemic sclerosis, SSc, n= 20) and from blood donors (n = 40). In order to evaluate
      functional properties of B cells, peripheral blood mononuclear cells (PBMC) from each group
      of patients are activated with CD40 ligand and CpG Oligodeoxynucleotides (CpG ODNs), and
      IL-10-producing B-cells are enumerated by FCM after a brief incubation with phorbol myristate
      acetate, ionomycin, and brefeldin A as a protein transport inhibitor agent. In selected CIS
      and MS patients whose changes in B-cell subpopulations associated with onset or progression
      of the disease are representative, the B-cell subpopulations will be purified and activated
      with CD40 ligand and CpG ODNs to be co cultured with anti-CD3-activated autologous T-cells to
      evaluate inhibitory or potentiating effects on T-cell production of pro-inflammatory
      cytokines (e.g. IFN-gamma, IL-17).

      All phenotypic analyses and cell cultures are performed using previously validated protocols.
      Our ultimate goal is to correlate quantitative and functional changes of subsets composing
      the systemic B-cell population with the grading and evolution of MS. Such a strategy could
      lead to identify which MS patients should receive treatment targeting B cells and when.
      Further, it may offer a rationale for alternative forms of cell therapy that could introduce
      for example autologous purified B regulator cells after depletive strategies.
    

Intervention name(s): Blood sample collection
Intervention type(s): Other
Intervention description(s): Peripheral blood will be collected in patients at the different time of the study to analyze phenotypic and functional properties of B cells in MS patients and control group
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Primary care clinic
      
Biospecimen description: 
      Blood samples to collect peripheral blood mononuclear cells Phenotypic and functional studies
      using flow cytometric approaches