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 antigen levels (vWF:Ag) and antiendothelial cell antibodies (AECA) as indices 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, and 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 correlated with disease activity scores, antineutrophil cytoplasmic antibodies (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 correlated with CRP levels but not with disease activity. vWF:Ag levels were elevated in patients (median 296% vs. controls 109%; p<0.001) and correlated with disease activity, ESR, CRP, ANCA titers, and serum creatinine levels. AECA levels did not differ from controls (5% vs. 7%).

CONCLUSION

Circulating levels of sIL-2r, sCD4, sCD8, and vWF:Ag are elevated in active WG, indicating T cell and endothelial activation. sIL-2r, sCD4, and vWF:Ag are potentially useful disease activity markers.