Lymphocyte activation markers and von Willebrand factor antigen in Wegener's granulomatosis: Potential markers for disease activity

Objective. To examine 3 soluble circulating T cell antigens: interleukin 2 receptors (sIL-2r), CD4 (sCD4), and CD8 (sCD8) with von Willebrand factor a ntigen levels (vWF:Ag) and antiendothelial cell antibodies (AECA) as indice s of endothelial involvement in patients with Wegener's granulomatosis (WG) . Methods. We studied 23 patients with WG, of whom 11 had active disease with renal involvement, and 20 healthy controls. sIL-2r, sCD4, sCD8, vWF:Ag, an d AECA were measured by ELISA. Results. Median sIL-2r levels in patients were higher than controls (789.5 vs 551 U/ml; p < 0.01). sCD4 levels were higher in patients: 17.0 vs 15.2 U /ml (p < 0.005) and correlated with sIL-2r levels, sIL-2r and sCD4 levels c orrelated with disease activity scores, antineutrophil cytoplasmic antibodi es (ANCA), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and neutrophil counts. sCD8 levels were also higher: 260.5 vs 127 U/ml (p < 0.001) and con elated with CRP levels but not with disease activity. vWF:A g levels were elevated in patients (median 296% vs controls 109%; p < 0.001 ) and correlated with disease activity, ESR, CRP, ANCA titers, and serum cr eatinine levels. AECA levels did not differ from controls (5% vs 7%). Conclusion. Circulating levels of sIL-2r, sCD4, sCD8, and vWF:Ag are elevat ed in active WG, indicating T cell and endothelial activation, sIL-2r: sCD4 , and vWF:Ag are potentially useful disease activity markers.