Fibronectin and circulating immune complexes in Behçet's disease

Abstract

Being a high-molecular-weight adhesive glycoprotein, fibronectin (Fn) is suggested to be a component of immune complexes and may participate in the clearance of immune complexes. In Behçet's disease (BD), a multisystem disorder of unknown etiology, immune complexes have been shown to be deposited in affected tissue during disease activity, suggesting an immune mechanism. This study investigates the relationship between Fn and circulating immune complexes (CIC) and evaluates the changes in the levels of Fn and CIC along with disease activity. In 63 patients (31 active, 32 inactive) with BD, plasma Fn and serum CIC, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and the third and fourth components of the complement system (C3, C4) were studied. The mean ESR, CRP, C3 and C4 levels of active BD patients were found to be significantly higher than those of the inactive BD patient group. Although the mean Fn and CIC levels of BD patients were not significantly different from those of the healthy control group, Fn and CIC values of active BD patients were significantly lower than in the inactive group. Moreover, no significant correlation was observed among Fn levels and ESR, CRP, C3, C4 and CIC levels in BD patients. The result of this study suggest that the variation in Fn concentration is independent of the acute-phase response. The lack of relationship between the CIC and Fn concentrations indicates that IC deposition in the vessel wall is independent of the CIC levels. In order to determine the exact roles of Fn and IC, further studies in tissue specimens are required.

Is there a relation between clinical disease activity and acute phase response in Behcet's disease?

“…They were found to be higher also in patients with active disease than in those in remission and controls . Also, the mean ESR, CRP, C3, and C4 levels of patients with active BD were determined to be significantly higher than those of the inactive BD patient group in another study . It was suggested that higher ESR levels were observed more frequently in patients with BD with erythema nodosum, vascular involvement, and HLAB51 positivity .…”

Immunopathogenesis of Behçet's Disease

“…Poulter and associates demonstrated a deposition of complement and an absence of fibrinoid changes by examining the aphthous ulcers of patients with BD (66). Others reported that the level of fibronectin, which possibly participates in the immune complex clearance, could not be correlated with the level of CIC, indicating that the level of immune complex of the vessel walls is independent of that of CIC (67).…”

Behçet's disease with severe destructive arthritis

“…4,9,13 Our patient also met the American Rheumatism Association 1987 revised criteria for the classification of RA. However, laboratory investigations showed that she was negative for rheumatoid factor, and neither ESR nor CRP was elevated at the time of the operation.…”