title: Validation of relapse risk biomarkers for routine use in patients with juvenile idiopathic arthritis.
abstract: OBJECTIVE
  The myeloid-related proteins 8 and 14 (MRP-8/MRP-14) and neutrophil-derived S100A12 are biomarkers of inflammation. They can be used to determine the relapse risk in patients with juvenile idiopathic arthritis (JIA) after stopping antiinflammatory treatment. In this study, we tested the performance of different enzyme-linked immunosorbent assays (ELISAs) in order to validate systems available for routine use.
  
  
  METHODS
  MRP-8/MRP-14 and S100A12 serum concentrations of 188 JIA patients in remission were analyzed. Commercially available test systems were compared to experimental ELISAs established in house. The ability of the assays to identify JIA patients at risk for relapse was analyzed.
  
  
  RESULTS
  For MRP-8/MRP-14, the PhiCal Calprotectin and Buhlmann MRP8/14 Calprotectin ELISAs revealed hazard ratios of 2.3 and 2.1, respectively. For S100A12, the CircuLex S100A12/EN-RAGE ELISA revealed a hazard ratio of 3.1. The commercial assays allowed a JIA relapse prediction that was at least comparable to the experimental ELISAs.
  
  
  CONCLUSIONS
  For the prediction of JIA relapse after stopping medication, the biomarkers MRP-8/MRP-14 and S100A12 can be determined by using assays that are available for routine use. The tested commercial MRP-8/MRP-14 and S100A12 ELISAs showed a performance comparable to well-established experimental ELISA protocols when assay-specific cutoffs for the indication of relapse prediction are thoroughly applied.
authors: Friederike
authors: F
authors: Rothmund
authors: Joachim
authors: J
authors: Gerss
authors: Nicolino
authors: N
authors: Ruperto
authors: Jan
authors: J
authors: Däbritz
authors: Helmut
authors: H
authors: Wittkowski
authors: Michael
authors: M
authors: Frosch
authors: Nico M
authors: NM
authors: Wulffraat
authors: Lucy R
authors: LR
authors: Wedderburn
authors: Dirk
authors: D
authors: Holzinger
authors: Faekah
authors: F
authors: Gohar
authors: Sebastiaan J
authors: SJ
authors: Vastert
authors: Riva
authors: R
authors: Brik
authors: Chantel Job
authors: CJ
authors: Deslandre
authors: Jose Antonio
authors: JA
authors: Melo-Gomes
authors: Claudia
authors: C
authors: Saad Magalhaes
authors: Roberto
authors: R
authors: Barcellona
authors: Ricardo
authors: R
authors: Russo
authors: Marco
authors: M
authors: Gattorno
authors: Alberto
authors: A
authors: Martini
authors: Johannes
authors: J
authors: Roth
authors: Dirk
authors: D
authors: Foell
mesh_terms: D000328:Adult; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001171:Arthritis, Juvenile / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy*; D015415:Biomarkers / Q000097:blood; D040501:Calgranulin A / Q000097:blood*; D040502:Calgranulin B / Q000097:blood*; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors; D009418:S100 Proteins / Q000097:blood*; D000067616:S100A12 Protein; D055502:Secondary Prevention
chemical_list: D018501:Antirheumatic Agents; D015415:Biomarkers; D040501:Calgranulin A; D040502:Calgranulin B; D009418:S100 Proteins; D000067616:S100A12 Protein; C090441:S100A12 protein, human