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Development and Validation of an Ultrasensitive Single Molecule Array Digital Enzyme-linked Immunosorbent Assay for Human Interferon-α
Published on: June 14, 2018
Should we measure the bioavailability of interferon beta in vivo in patients with multiple sclerosis?
Bernhard Hemmer1, Achim Berthele
1Department of Neurology, Technische Universität München, Munich, Germany. hemmer@lrz.tu-muenchen.de
This commentary discusses a study by van der Voort et al. that tested the diagnostic value of in vivo interferon beta (IFN-beta) bioactivity screening in identifying patients with multiple sclerosis who have developed neutralizing antibodies (NAbs) to IFN-beta therapy--an event that limits the efficacy of the therapy. The in vivo assay used by the authors, which measures expression of the IFN-beta-stimulated gene MxA (MX1) in the peripheral blood, indicated lack of a biological response in 19 of 23 patients with high-titer NAbs following injection of IFN-beta. However, an abnormal response was also observed in 18 of 55 patients who had low-titer NAbs or were NAb negative. The authors concluded that in patients treated with IFN-beta a single postinjection measurement of MxA messenger RNA expression is adequate to determine the IFN-beta bioactivity status. While we believe that in vivo measurement of MxA messenger RNA following IFN-beta injection is a reliable test by which to identify patients with inadequate response to IFN-beta, the capacity of the test to predict treatment failure must be established in a well-designed, prospective trial.
This commentary discusses a study by van der Voort et al. that tested the diagnostic value of in vivo interferon beta (IFN-beta) bioactivity screening in identifying patients with multiple sclerosis who have developed neutralizing antibodies (NAbs) to IFN-beta therapy--an event that limits the efficacy of the therapy. The in vivo assay used by the authors, which measures expression of the IFN-beta-stimulated gene MxA (MX1) in the peripheral blood, indicated lack of a biological response in 19 of 23 patients with high-titer NAbs following injection of IFN-beta. However, an abnormal response was also observed in 18 of 55 patients who had low-titer NAbs or were NAb negative. The authors concluded that in patients treated with IFN-beta a single postinjection measurement of MxA messenger RNA expression is adequate to determine the IFN-beta bioactivity status. While we believe that in vivo measurement of MxA messenger RNA following IFN-beta injection is a reliable test by which to identify patients with inadequate response to IFN-beta, the capacity of the test to predict treatment failure must be established in a well-designed, prospective trial.
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