Multiple sclerosis: Pro- and anti-inflammatory cytokines and metalloproteinases are affected differentially by treatment with IFN-beta

Interferon-beta (IFN-beta) has a beneficial influence on the course of mult iple sclerosis (MS) and has become standard treatment of this disease, thou gh its mechanisms of action are incompletely understood. This study examine s the effect of IFN-beta treatment on the cytokines IL-6, TNF-alpha, IFN-ga mma and IL-10; the metalloproteinases MMP-3, -7 and -9 and the tissue inhib itor of metalloproteinase-1 (TIMP-1). IFN-beta treatment resulted in decrea sed numbers of mononuclear cells (MNC) secreting IL-6 and TNF-alpha and exp ressing mRNA of MMP-3 and MMP-9 compared to pretreatment levels. On the con trary, numbers of IL-10 secreting MNC and TIMP-1 mRNA expressing were augme nted during IFN-beta therapy. Whether the down-regulatory effects on pro-in flammatory and upregulatory effects on anti inflammatory molecules are a di rect result of IFN-beta on the immune system or secondary to clinical stabi lization of MS pathology induced by IFN-beta remains to be evaluated. (C) 2 000 Elsevier Science B.V. All rights reserved.