B. Van Wijmeersch

The effect of disease-modifying treatments on conversion to secondary progressive multiple sclerosis

Patients suffering from multiple sclerosis (MS) are increasing in developed countries. Considering the physical and socioeconomical burden of MS, the cause for the increasing trend should be intensively investigated. Of note, the trend of increasing incidence of MS is most obvious in Japan, referring to a government report on the registered cases of MS. Although only 1000 patients with MS or neuromyelitis optica (NMO) were registered in 1980, there are currently more than 20,000 patients with MS/ NMO. The increase is more significant in MS than NMO, resulting in an increase in MS/NMO ratio. Regional epidemiological survey in Tokachi, Hokkaido (Houzen et al.) indicates that the increase is the reality, and not due to better awareness of the disease, improved health care system or better medical facilities. Among environmental risk factors for MS, cigarette smoking, lower exposure to sunlight, EB virus infection, or higher salt taking could not explain the increase. In the symposium, I discuss that westernization and changes in diet may at least partly explain the increase of patients with MS in Japan, possibly via altering gut microbiota and immune regulatory network.

Significant and Meaningful Improvement in Treatment Satisfaction with Teriflunomide Versus Subcutaneous IFNB-1A in Patients with Relapsing MS Results from Tenere

[Maeurer, M.] Caritas Krankenhaus Bad Mergentheim, Bad Mergentheim, Germany. [Van Wijmeersch, B.] Hasselt Univ, Diepenbeek, Belgium. [de Seze, J.] Strasbourg Univ, Strasbourg, France. [Meca-Lallana, J.] Univ Catolica San Antonio de Murcia, Murcia, Spain. [Bozzi, S.] Sanofi, Chilly Mazarin, France. [Vermersch, P.] Univ Lille Nord France, Lille, France.

Dimethyl fumarate induces a persistent change in the composition of the innate and adaptive immune system in multiple sclerosis patients

The effects of dimethyl fumarate (DMF) on the immune system in multiple sclerosis (MS) are not completely elucidated. In this study, an extensive immunophenotypic analysis of innate and adaptive immune cells of DMF-treated MS patients was performed. Peripheral blood immune cell phenotypes were determined using flow cytometry in a follow-up study of 12 MS patients before, after 3 and 12 months of DMF treatment and a cross-sectional study of 25 untreated and 64 DMF-treated MS patients. Direct effects of DMF on B cells were analyzed in vitro. After 12 months of DMF treatment, percentages of monocytes, natural killer cells, naive T and B cells and transitional B cells increased. Percentages of (effector) memory T cells, (non) class-switched memory B cells and double negative B cells decreased together with CD4+ T cells expressing interferon-γ (IFN-γ), granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin-17 (IL-17). DMF treatment was fully effective as of 6 months and directly induced apoptosis and decreased expression of costimulatory CD40, antigen presentation molecule MHCII and B cell activating factor receptor (BAFFR) on B cells. DMF induced a persistent change of the immune system of MS patients, directly induced apoptosis and reduced expression of functional markers on B cells.