Real-time TaqMan assay for myxovirus resistance protein (MxA) mRNA: a robust marker of interferon beta bioactivity in patients with multiple sclerosis

For many patients suffering from MS, interferon beta (IFNβ) is an effective therapeutic option; however, some patients who receive long-term IFNβ therapy for relapsing-remitting MS (RRMS) develop neutralizing antibodies (NAbs) that affect IFNβ efficacy. It is therefore important to evaluate patients' therapeutic response to IFNβ over time. Myxovirus resistance protein A (MxA), a surrogate marker of individual immunologic response to IFNβ, may be a useful tool for assessing IFNβ immunogenicity. The real-time TaqMan assay for MxA messenger RNA (mRNA) has several distinct advantages, including the ability to amplify and complete quantitative analyses in one step, a high degree of quality control and prior experience and confidence in the field of quantitative viral diagnostics. The real-time TaqMan assay for MxA mRNA can be incorporated as a component of IFNβ therapy to evaluate patients during the course of treatment. Multiple Sclerosis 2007; 13: S49—S52. http://msj.sagepub.com