Ab1804

Circulating cytokines and soluble CD23, CD26 and CD30 in ANCA-associated vasculitides

U. Schönermarck, E. Csernok, A. Trabandt, H. Hansen¹, W.L. Gross

Department of Rheumatology, Medical University of Lübeck and Rheumaklinik Bad Bramstedt, Germany; and ¹Department of Biochemistry, University of Kiel, Germany.

ABSTRACT
Objective
To assess circulating immunoregulatory cytokines and soluble surface markers of T and B cell activation in the plasma of patients with Wegener's granulomatosis (WG), Churg-Strauss syndrome (CSS) and microscopic polyangiitis (MPA) during active and inactive diseas, in order to establish their value in discriminating between disease entities and as markers of disease activity.

Methods
Plasma levels of IL-4, IL-5, IL-10, IL-12, IL-13, IFN-g and soluble CD23, CD26 and CD30 were determined by enzyme-linked immunosorbent assay in patients with WG (n = 21), CSS (n = 19) and MPA (n = 14) during active disease and remission.

Results
Concerning cytokines, no differences were observed for IFN-g, IL-4, IL-5 and IL-13. Plasma levels of IL-12 were decreased in all subgroups of patients. On the contrary, IL-10 levels were significantly elevated only in patients with CSS. Levels of sCD30 were significantly increased in patients with active generalized WG and CSS, but not in those with MPA and localized WG, correlating with the disease extent and activity. sCD26 levels were markedly decreased in patients with generalized WG, CSS and MPA and increased towards remission. sCD23 levels were slightly, but not significantly increased in CSS and generalized WG.

Conclusion
Regarding the investigated immunoregulatory cytokines (Th1/Th2 type), only the measurement of plasma levels of IL-10 discriminated CSS from WG and MPA. The reported data could indicate a similar status of T cell activation in generalized WG and CSS, and possibly a shift in peripheral immunity towards a more humoral dominated immune response. The differences observed between patients with the localized and generalized forms of WG seem to reflect the clinically known biphasic course of this disease.

Key words
Vasculitis, ANCA cytokine, soluble CD26, soluble CD30.

Please address correspondence and reprint requests to: E. Csernok, PhD, Rheumaklinik Bad Bramstedt, D-24572 Bad Bramstedt, Germany.
E-mail: c.moeck@rheuma-zentrum.de