title: MxA mRNA decrease preceding NAb detection in IFNβ-treated MS patients.
abstract: Multiple sclerosis (MS) patients treated with interferon beta (IFNβ) are at risk of a declining response to treatment because of the production of IFNβ-neutralizing antibodies (NAbs). The expression of Myxovirus resistance protein A (MxA) mRNA is regarded as a marker of IFNβ bioactivity.
  
  
  
  The aim of this study was to analyze the kinetics of MxA mRNA expression during long-term IFNβ treatment and assess its relationship to NAb production.
  
  
  
  A prospective, observational, open-label, non-randomized study was designed in multiple sclerosis patients starting IFNβ treatment. NAbs and MxA mRNA were monitored every six months.
  
  
  
  119 patients were consecutively enrolled and 107 were included in the final analysis. Both the presence of NAbs and a decrease in MxA mRNA below the cut off were revealed in 15 patients, however, in six patients (40%) positivity for NAbs was preceded by the decrease in MxA mRNA. In addition, a further six patients showing a decline in MxA mRNA did not have detectable NAbs.
  
  
  
  Our data indicate that quantification of MxA mRNA is a more sensitive identifier of loss of IFNβ efficacy than the NAb positivity.
authors.affiliation: Department of Neurology Charles University 2nd Faculty of Medicine and Motol University Hospital Prague Czech Republic.
authors.forename: Jana
authors.identifier: 0000-0001-9737-0507
authors.initials: J
authors.lastname: Libertinova
authors.affiliation: Department of Neurology Charles University 2nd Faculty of Medicine and Motol University Hospital Prague Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Meluzinova
authors.affiliation: Laboratory of Molecular Diagnostics Na Homolce Hospital Prague Czech Republic.
authors.forename: Vaclav
authors.initials: V
authors.lastname: Matoska
authors.affiliation: Department of Medical Microbiology, Charles University 2nd Faculty of Medicine and Motol University Hospital Prague Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Zajac
authors.affiliation: Department of Neurology and Center of Clinical Neuroscience Charles University First Faculty of Medicine and General University Hospital Prague Czech Republic.
authors.forename: Ivana
authors.initials: I
authors.lastname: Kovarova
authors.affiliation: Department of Neurology and Center of Clinical Neuroscience Charles University First Faculty of Medicine and General University Hospital Prague Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Havrdova
authors.affiliation: Department of Neurology and Center of Clinical Neuroscience Charles University First Faculty of Medicine and General University Hospital Prague Czech Republic.
authors.forename: Dana
authors.initials: D
authors.lastname: Horakova
authors.affiliation: Department of Neurology Charles University 2nd Faculty of Medicine and Motol University Hospital Prague Czech Republic.
authors.forename: Ales
authors.initials: A
authors.lastname: Tomek
authors.affiliation: Department of Neurology Charles University 2nd Faculty of Medicine and Motol University Hospital Prague Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Marusic
authors.affiliation: Department of Neurology Charles University 2nd Faculty of Medicine and Motol University Hospital Prague Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Bojar
mesh_terms: D000328:Adult; D057134:Antibodies, Neutralizing / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016899:Interferon-beta / Q000276:immunology* / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood* / Q000188:drug therapy*; D064547:Myxovirus Resistance Proteins / Q000097:blood*; D017063:Outcome Assessment, Health Care; D012333:RNA, Messenger / Q000097:blood*; D055815:Young Adult
chemical_list: D057134:Antibodies, Neutralizing; C579071:MX1 protein, human; D064547:Myxovirus Resistance Proteins; D012333:RNA, Messenger; D016899:Interferon-beta
keywords: MxA; MxA mRNA; bioactivity; interferon beta; multiple sclerosis; neutralizing antibodies