Serum level of APRIL/BLyS in Behçet’s disease patients: clinical significance in uveitis and disease activity

Abstract

Objective The aim of the study reported here was to assess the serum concentration of B-cell activating factors, B lymphocyte stimulators (BLyS), and a proliferation-inducing ligand (APRIL) in Behçet disease (BD) patients in order to evaluate their role and study their relation to uveitis subtype and disease activity.

Methods The study included 58 consecutively recruited BD patients with a mean age of 35.54 ± 8.85 years and disease duration of 8.33 ± 5.84 years and 30 age- and sex-matched controls. Disease activity was assessed using the BD current activity form score. Patients were subclassified according to the presence and type of uveitis. Serum BLyS and APRIL were measured by enzyme-linked immunosorbent assay.

Results Recurrent uveitis was present in 42 (72.41 %) patients, of whom 19 had the anterior form, 13 had the posterior form, and ten had a combined anterior with posterior form; 16 had no eye involvement. Serum APRIL (60.29 ± 57.99 ng/ml) and BLyS (2.31 ± 1.97 ng/ml) levels were significantly higher in the BD patients than in the controls (4.14 ± 4.31 and 0.49 ± 0.39 ng/ml, respectively; P < 0.0001). The levels were clearly higher in those with combined uveitis. The BLyS level significantly correlated with disease activity.

Conclusions The overexpression of BLyS and APRIL in BD patients supports the notion of a critical role for B cell activation factors in BD, particularly in terms of uveitis and disease activity. This provides an interesting prospect for the use of anti-BLyS/APRIL antibodies against future therapeutic targets.

Keywords::

• Behçet’s disease
• Uveitis
• APRIL
• BLyS