title: Predicting autoimmunity after alemtuzumab treatment of multiple sclerosis.
abstract: OBJECTIVE
  We have previously shown that autoimmunity following alemtuzumab treatment of multiple sclerosis can be predicted by high baseline serum interleukin IL-21 (IL-21), as measured using a now 'redundant' enzyme linked immunosorbent assay (ELISA). Here we ask whether currently available ELISAs have similar prognostic value.
  
  
  METHODS
  Serum IL-21 from 141 individuals with relapsing remitting multiple sclerosis was measured using the now 'redundant' IL-21 ELISA and five further currently available kits. All patients had been treated with alemtuzumab; 61/141 had developed secondary autoimmunity.
  
  
  RESULTS
  The 'redundant kit', and one current kit, confirmed higher baseline serum IL-21 in patients with autoimmunity (542 pg/mL vs. 222 pg/mL and 53.1 pg/mL vs. 9.3 pg/mL respectively) and showed positive correlation. However, only the 'redundant' kit had predictive utility.
  
  
  CONCLUSIONS
  Currently available IL-21 ELISA kits should not be used to counsel individuals with multiple sclerosis considering treatment with alemtuzumab.
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Laura
authors.initials: L
authors.lastname: Azzopardi
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Sara A J
authors.initials: SA
authors.lastname: Thompson
authors.affiliation: Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, UK.
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Harding
authors.affiliation: Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Cossburn
authors.affiliation: Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, UK.
authors.forename: Neil
authors.initials: N
authors.lastname: Robertson
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Alastair
authors.initials: A
authors.lastname: Compston
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Alasdair J
authors.initials: AJ
authors.lastname: Coles
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.
authors.forename: Joanne L
authors.initials: JL
authors.lastname: Jones
mesh_terms: D000293:Adolescent; D000328:Adult; D000074323:Alemtuzumab; D061067:Antibodies, Monoclonal, Humanized / Q000009:adverse effects / Q000627:therapeutic use*; D001327:Autoimmune Diseases / Q000097:blood / Q000139:chemically induced* / Q000175:diagnosis; D015551:Autoimmunity / Q000187:drug effects; D015415:Biomarkers / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007378:Interleukins / Q000097:blood; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy*; D011237:Predictive Value of Tests; D055815:Young Adult; D000098546:Interleukin-21
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D015415:Biomarkers; D007378:Interleukins; D000074323:Alemtuzumab; D000098546:Interleukin-21
keywords: Immunology; Multiple Sclerosis