Cytokines and disability in interferon-β-1b treated and untreated women with multiple sclerosis

T-helper (Th) cells involved in the pathogenesis of multiple sclerosis (MS) represent a functionally heterogeneous population defined by their cytokine secretion profile. The effects of immunotherapeutic drugs on the cytokine network are still not fully clarified. This study aimed to investigate serum levels of IFN-γ, TNF-α, IL-4, IL-10 in interferon-β-1b-treated and untreated women with relapsing-remitting MS (RRMS) in comparison with healthy controls and the relationship between cytokine concentrations and the degree of disability.

The study included 35 women with RRMS and 35 age-matched healthy controls. The patients were divided in two groups: Group A-without disease modifying treatment; Group B-treated with interferon-β-1b. Degree of disability was assessed by the Expanded Disability Status Scale (EDSS). Serum cytokine concentrations were measured by ELISA during relapse and remission.

Group A showed higher IFN-γ in remission (p = 0.0239) than the controls; Group B had lower IFN-γ during relapse (p = 0.0226) than controls. EDSS in relapse correlated with the levels of IL-10 for Group A (p = 0.015) and with the concentration of IFN-γ for Group B (p = 0.039). Nontreated patients showed higher EDSS in relapse compared to the interferon-β-1b-treated group (p = 0.005).

We found an imbalance in the patients' cytokine profile, which may be seen as supportive of the hypothesis that demyelination in the central nervous system is mediated by Th1 lymphocytes. IFN-γ is probably one of the important indicators for intensity of the immune reaction and shows promise as a potential biomarker for the therapeutic effect of interferon-β-1b. The role of IL-10 in the autoimmune process needs further investigation.