Interleukin-1 receptor antagonist in neonates, children and adults, and in patients with pauci- and polyarticular onset juvenile chronic arthritis

Clin Exp Rheumatol. Jul-Aug 1997;15(4):439-44.


Objective: The production of interleukin (IL) -1 alpha IL-1 beta and IL-1 receptor antagonist (IL-1ra) by blood mononuclear cells (MNC), as well as the corresponding serum levels of IL-1ra were examined in blood samples from umbilical cords (n = 11), children (n = 40) and adults (n = 20), and in 42 patients with juvenile chronic arthritis (JCA) of the pauci- or polyarticular onset type.

Results: IL-1ra serum levels were found to differ significantly between the three age groups, being higher in neonates (569 pg/ml) than in children (70 pg/ml) and adults (177 pg/ml). IL-1ra production in E. coli lipopolysacharide (LPS) stimulated-cultures of MNC was also significantly higher in neonates (median 2451 pg/ml) than in children (1526 pg/ml), but similar to that in adults (2107 pg/ml). IL-1ra levels in the sera of both subgroups of JCA patients were significantly elevated (median 257 pg/ml), but did not reflect paraclinical or clinical disease parameters. In samples of synovial fluid the IL-1ra levels tended to be fairly high, up to approximately 2 ng/ml, but they did not reflect the serum levels of IL-1ra.

Conclusion: These findings suggests that the upregulation of IL-1ra production forms part of the immunoregulatory response in JCA patients, and that the insufficient production of IL-1ra is unlikely to contribute to the pathogenesis of JCA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Arthritis, Juvenile / blood*
  • Cells, Cultured
  • Child
  • Child, Preschool
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Fetal Blood / metabolism
  • Flow Cytometry
  • Humans
  • Infant, Newborn
  • Interleukin 1 Receptor Antagonist Protein
  • Interleukin-1 / blood
  • Male
  • Middle Aged
  • Monocytes / metabolism
  • Receptors, Interleukin-1 / antagonists & inhibitors*
  • Sialoglycoproteins / blood*
  • Synovial Fluid / metabolism
  • Up-Regulation


  • IL1RN protein, human
  • Interleukin 1 Receptor Antagonist Protein
  • Interleukin-1
  • Receptors, Interleukin-1
  • Sialoglycoproteins