Elevation of the Soluble form GPI-80, a β2 Integrin-associated Glycosylphosphatidylinositol Anchored Protein, in the Serum of Patients with Wegener's Granulomatosis

Abstract

The purpose of present study is to determine the value of serum levels of the soluble form of β2 integrin-associated glycosylphosphatidylinositol (GPI)-anchored glycoprotein (GPI-80) for monitoring disease activity during the clinical course of the disease, in a total of 24 serum samples from 9 patients with Wegener's granulomatosis (WG). The serum soluble form GPI-80 (sGPI-80) concentrations of WG patients were measured by enzyme-linked immunosorbent assay (ELISA). The titers of anti-neutrophil cytoplasmic antibody (ANCA) were assessed by an indirect immunofluorescence method. The serum concentrations of tumor necrosis factor-a (TNF-a), soluble TNF receptor (sTNFR) I and II, soluble interleukin-2 receptor, and soluble intracellular adhesion molecule-1 of WG patients were also measured by ELISA. The serum sGPI-80 levels were significantly elevated in active WG and were positively correlated with disease activity. At the time of remission, a significant decrease in GPI-80 was observed. The serum sGPI- 80 levels were correlated with the ANCA titer and the concentrations of sTNFR I and II. These findings suggest that sGPI-80 is useful as an additional measure of WG activity.