CYTOKINE PROFILE IN INTERFERON-BETA TREATED MULTIPLE-SCLEROSIS PATIENTS - REDUCTION OF INTERLEUKIN-10 MESSENGER-RNA EXPRESSING CELLS IN PERIPHERAL-BLOOD

Treatment with interferon-beta reduces relapse rate, slows progression of neurological disability and reduces the number of active brain les ions observed with magnetic resonance imaging in relapsing-remitting m ultiple sclerosis. Interferon-beta has antiviral properties, but in ad dition it affects the expression of several immunoregulatory genes, in cluding genes for cytokines such as interferon-gamma and interleukin-1 0. Cytokines are believed to be central in the pathologic process in m ultiple sclerosis, by regulating autoreactive T- and B-cell responses. In this study we have determined effects of interferon-beta on the fr equency of cells in peripheral blood and cerebrospinal fluid expressin g mRNA for interferon-gamma, tumor necrosis factor-alpha, interleukin- 4 and interleukin-10 in a group of multiple sclerosis patients. All pa tients were treated for two months or more, since the beneficial effec t of interferon-beta is not apparent until after several months of tre atment. We detected a significant reduction of interleukin-10 mRNA exp ressing cells in the peripheral blood during interferon-beta treatment compared with pretreatment values (10 vs 33 cells/10(5); p = 0.028) w hile the other investigated cytokines were not significantly affected. We conclude that there is a long term effect of interferon-beta on cy tokine expression in multiple sclerosis patients. Its relation to the therapeutic effect is as yet not clear.