No evidence for increased frequency of autoantibodies during interferon-beta1b treatment of multiple sclerosis.

Interferon-beta1b (IFN-beta1b) is a widespread therapy of multiple sclerosis (MS), reducing the numbers and severity of exacerbations and the total lesion load measured by magnetic resonance imaging of the brain. Since IFN-beta1b has potent immunomodulatory properties, a potential side-effect of IFN-beta1b treatment could be the development of autoimmune responses. The frequencies of antinuclear and smooth muscle antibodies, antibodies against microsomal antigen of thyroid epithelial cells as well as a group of heterophilic antibodies were determined in 26 MS patients treated with IFN-beta1b for 3-20 months. No elevation of antibody titres was found for any of the antibodies studied when compared with paired samples obtained from most of the patients before the initiation of treatment. Although examined on a rather small group of patients, the results show no evidence of increased frequency of autoantibodies during interferon-beta1b treatment of multiple sclerosis.