MRP8/14 serum levels as a predictor of response to starting and stopping anti-TNF treatment in juvenile idiopathic arthritis

Arthritis Res Ther. 2015 Aug 7;17(1):200. doi: 10.1186/s13075-015-0723-1.


Introduction: Approximately 30% of juvenile idiopathic arthritis (JIA) patients fail to respond to anti-TNF treatment. When clinical remission is induced, some patients relapse after treatment has been stopped. We tested the predictive value of MRP8/14 serum levels to identify responders to treatment and relapse after discontinuation of therapy.

Methods: Samples from 88 non-systemic JIA patients who started and 26 patients who discontinued TNF-blockers were analyzed. MRP8/14 serum levels were measured by in-house MRP8/14 ELISA and by Bühlmann Calprotectin ELISA at start of anti-TNF treatment, within 6 months after start and at discontinuation of etanercept in clinical remission. Patients were categorized into responders (ACRpedi ≥ 50 and/or inactive disease) and non-responders (ACRpedi < 50) within six months after start, response was evaluated by change in JADAS-10. Disease activity was assessed within six months after discontinuation.

Results: Baseline MRP8/14 levels were higher in responders (median MRP8/14 of 1466 ng/ml (IQR 1045-3170)) compared to non-responders (median MRP8/14 of 812 (IQR 570-1178), p < 0.001). Levels decreased after start of treatment only in responders (p < 0.001). Change in JADAS-10 was correlated with baseline MRP8/14 levels (Spearman's rho 0.361, p = 0.001). Patients who flared within 6 months after treatment discontinuation had higher MRP8/14 levels (p = 0.031, median 1025 ng/ml (IQR 588-1288)) compared to patients with stable remission (505 ng/ml (IQR 346-778)). Results were confirmed by Bühlmann ELISA with high reproducibility but different overall levels.

Conclusion: High levels of baseline MRP8/14 are associated with good response to anti-TNF treatment, whereas elevated MRP8/14 levels at discontinuation of etanercept are associated with higher chance to flare.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / blood*
  • Adolescent
  • Antirheumatic Agents / administration & dosage
  • Arthritis, Juvenile / blood*
  • Arthritis, Juvenile / diagnosis
  • Arthritis, Juvenile / drug therapy*
  • Biomarkers / blood
  • Calgranulin B / blood*
  • Child
  • Child, Preschool
  • Drug Administration Schedule
  • Etanercept / administration & dosage*
  • Female
  • Humans
  • Male
  • Predictive Value of Tests
  • Prospective Studies
  • Treatment Outcome
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors*


  • ABCC11 protein, human
  • ATP-Binding Cassette Transporters
  • Antirheumatic Agents
  • Biomarkers
  • Calgranulin B
  • Tumor Necrosis Factor-alpha
  • Etanercept