Background: Dimethyl fumarate (DMF) alters the phenotype of circulating immune cells and causes lymphopenia in a subpopulation of treated multiple sclerosis (MS) patients. Objective: To phenotypically characterize circulating leukocytes in DMF-treated MS patients. Methods: Cross-sectional observational comparisons of peripheral blood from DMF-treated MS patients (n = 17 lymphopenic and n = 24 non-lymphopenic), untreated MS patients (n = 17) and healthy controls (n = 23); immunophenotyped using flow cytometry. Longitudinal samples were analyzed for 13 DMF-treated patients. Results: Lymphopenic DMF-treated patients had significantly fewer circulating CD8+ and CD4+ T cells, CD56dim natural killer (NK) cells, CD19+ B cells and plasmacytoid dendritic cells when compared to controls. CXCR3+ and CCR6+ expression was disproportionately reduced among CD4+ T cells, while the proportion of T-regulatory (T-reg) cells was unchanged. DMF did not affect circulating CD56hi NKcells, monocytes or myeloid dendritic cells. Whether lymphopenic or not, DMF-treated patients had a lower proportion of circulating central and effector memory T cells and concomitant expansion of naïve T cells compared to the controls. Conclusions: DMF shifts the immunophenotypes of circulating T cells, causing a reduction of memory cells and a relative expansion of naïve cells, regardless of the absolute lymphocyte count. This may represent one mechanism of action of the drug. Lymphopenic patients had a disproportionate loss of CD8+ T-cells, which may affect their immunocompetence.
|Titolo:||Dimethyl fumarate selectively reduces memory T cells in multiple sclerosis patients|
|Parole Chiave:||Dimethyl fumarate; immunocompetence; immunology; lymphocyte types; lymphopenia; memory T cells; multiple sclerosis; neuroimmunology; relapse|
|Settore Scientifico Disciplinare:||Settore MED/26 - Neurologia|
|Data di pubblicazione:||2016|
|Digital Object Identifier (DOI):||10.1177/1352458515608961|
|Appare nelle tipologie:||01 - Articolo su periodico|