Induction of sTNF-R1 and sTNF-R2 by interferon beta-1b in correlation withclinical and MRI activity

Objectives - To investigate the influence of interferon (IFN) beta-lb on th e serum levels of sTNF-R1, sTNF-R2 and TNF-beta in patients with multiple s clerosis (MS) in correlation with clinical and MRI activity. Materials and methods - Serum samples were obtained every 3 months from 24 patients treat ed with 8 x 10(6) U of IFN beta-1b every other day (treatment group) and fr om 21 patients without any immunomodulatory therapy (control group) over a 15-month observation period. The cytokine levels were measured by ELISA. Cr anial MRI was performed every 6 months to determine the burden of disease o f every patient. Results - In the treatment group we found an obvious incre ase of sTNF-R1 and sTNF-R2 (P<0.001) and relatively stable serum levels of TNF-beta with no statistical significance (P=0.56). In the control group, s TNF-R1 showed a significant decrease (P<0.001) during the same observation period of 15 months. During the 15-month observation period, the MRI-respon ders group had significant larger mean AUC (area under the concentration-ti me curve) values of sTNF-R1 (P=0.04) and sTNF-R2 (P=0.01) when compared to the group of MRI-nonresponders. Conclusion - The present data suggest that IFN beta-lb induces the expression and shedding of TNF-R1 and TNF-R2. The m agnitude of an increase of sTNF-Rs may be a marker for the effectiveness of treatment with IFN beta-1b.