Figure 2. DF ameliorates experimental autoimmune encephalomyelitis and suppresses GM-CSF–producing Th1 cells in the CNS.

(A) Wild-type B6 mice were immunized with 200 μg of MOG_35–55 and were treated with DF (treatment group) or placebo (control group) by oral administration starting on the day of immunization. Clinical signs were scored daily following a 0–5 scale. Data represent 1 of 3 experiments and the mean clinical scores ± SEM (n = 5 each group). (B) CNS-infiltrating cells from DF-treated and control mice were isolated on day 23 of disease. DF treatment significantly decreased total CD4⁺ T cells and GM-CSF–producing CD4⁺ T cells among CNS-infiltrating cells. (C) Cells were stained with GM-CSF, IFN-γ, and IL-17A antibodies and analyzed by flow cytometry. We found that GM-CSF was decreased in Th1 cells, but not Th17 cells, after DF treatment. (D) Splenocytes from both treated and control groups were collected and cultured/stimulated with 25 μg/mL MOG_35–55 for 72 hours. Concentrations of GM-CSF, IFN-γ, and IL-17A in culture supernatants were measured by ELISA. There was significantly less GM-CSF and IFN-γ in treated mice compared with controls. **p < 0.01; and ***p < 0.001. One of 2 experiments is shown. DF = dimethyl fumarate; GM-CSF = granulocyte macrophage colony-stimulating factor; IL = interleukin; MOG = myelin oligodendrocyte glycoprotein; SEM = standard error of the mean.