Objectives: To investigate the in vivo effect of corticosteroid pulse therapy on immunocompetent cells in 18 patients given methylprednisolone to treat an acute episode of MS.
Material and methods: Blood was sampled before and after 3 days of methylprednisolone administration at doses of 1 g/day. Lymphocyte subtyping was performed and whole blood cell cultures were used to measure the cytokine producing capacity for interleukin-1 (IL-1), interleukin-2 (IL-2), interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) and interferon-alpha (IFN-alpha). In addition, serum levels of the immunoglobulin classes IgG, IgA and IgM were determined.
Results: Before treatment, production of IL-1 was significantly increased in MS patients as compared to healthy controls. After therapy, production of all cytokines was significantly decreased, whereas there were significant increases in the numbers of monocytes, neutrophils and T and B lymphocytes. Treatment had no effect on serum immunoglobulin levels.
Conclusion: An important mechanism for the antiinflammatory effect of corticosteroids in MS results from a suppression of the activation of the peripheral immune compartment through inhibition of cytokine production and lymphocyte endothelial adhesiveness.