Interleukin-18 binding protein in the sera of patients with Wegener's granulomatosis

J Clin Immunol. 2009 Jan;29(1):38-45. doi: 10.1007/s10875-008-9217-0. Epub 2008 Jul 2.


Introduction: In the present study, we examined the levels of the pro-inflammatory cytokine IL-18 and its natural inhibitor, the IL-18 binding protein (IL-18BP), in sera of Wegener's granulomatosis (WG) patients at various stages of the disease.

Patients and methods: Sera from eight consecutive biopsy-proven systemic WG patients (four men and four women; age at diagnosis 58.4 +/- 13.8 years) were obtained longitudinally with a follow-up period of 55.2 +/- 30 months. Sera obtained from 50 healthy subjects were used as controls.

Results and discussion: Serum levels of IL-18, IL-18BP, and free IL-18 obtained during an active phase of the disease (Birmingham Vasculitis Activity Score, BVAS > 10) were more than twofold higher than levels in the same patients during inactive disease stages (BVAS < 5; P < 0.002; P < 0.006, and P < 0.03 for IL-18, IL-18BP, and free IL-18, respectively). During inactive stages, the levels of these markers were comparable to those of healthy controls. The elevated levels of IL-18 and IL-18BP in sera during active stages of disease suggest a possible role in the pathogenesis and course of the WG.

Conclusion: Despite the elevated IL-18BP levels during active disease, free IL-18 remained higher than in the inactive disease stages, suggesting a potential benefit of administration of exogenous IL-18BP as a novel therapeutic approach for active WG.

MeSH terms

  • Aged
  • Biomarkers / blood
  • Female
  • Follow-Up Studies
  • Granulomatosis with Polyangiitis / blood*
  • Granulomatosis with Polyangiitis / diagnosis
  • Humans
  • Intercellular Signaling Peptides and Proteins / blood*
  • Interleukin-18 / blood*
  • Longitudinal Studies
  • Male
  • Middle Aged


  • Biomarkers
  • Intercellular Signaling Peptides and Proteins
  • Interleukin-18
  • interleukin-18 binding protein