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


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.


CONCLUSIONS
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.


CONCLUSIONS
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.
Novick
D
D
Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel. daniela.novick@weizmann.ac.il
Elbirt
D
D
Dinarello
C A
CA
Rubinstein
M
M
Sthoeger
Z M
ZM
D000368:Aged; D015415:Biomarkers / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D014890:Granulomatosis with Polyangiitis / Q000097:blood* / Q000175:diagnosis; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D020382:Interleukin-18 / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged
D015415:Biomarkers; D036341:Intercellular Signaling Peptides and Proteins; D020382:Interleukin-18; C118370:interleukin-18 binding protein