Statins as immunomodulators

Abstract
Background: Recent data suggest that statins may be potent immunomodulatory agents. In order to evaluate the potential role of statins as immunomodulators in MS, the authors studied their immunologic effects in vitro and compared them to interferon (IFN)β-1b. Methods: Peripheral blood mononuclear cells (PBMC) obtained from untreated or IFNβ-1–treated patients with relapsing-remitting MS or from healthy donors (HD) and T cells were stimulated with concanavalin A, phytohemagglutinin, or antibody to CD3 in the presence of lovastatin, simvastatin, mevastatin, IFNβ-1b, or statins plus IFNβ-1b. The authors analyzed proliferative activity of T cells and B cells, cytokine production and release, activity of matrix metalloproteinases (MMP), and surface expression of activation markers, adhesion molecules, and chemokine receptors on both T and B cells. Results: All three statins inhibited proliferation of stimulated PBMC in a dose-dependent manner, with simvastatin being the most potent, followed by lovastatin and mevastatin. IFNβ-1b showed a similar effect; statins and IFNβ-1b together added their inhibitory potentials. Furthermore, statins reduced the expression of activation-induced adhesion molecules on T cells, modified the T helper 1/T helper 2 cytokine balance, reduced MMP-9, and downregulated chemokine receptors on both B and T cells. Besides strong anti-inflammatory properties, statins also exhibited some proinflammatory effects. Conclusions: Statins are effective immunomodulators in vitro that merit evaluation as treatment for MS.