Expression of high mobility group box 1 protein in patients with ankylosing spondylitis

Abstract

Objective To investigate the role of high mobility group box l protein (HMGB1) in the pathogenesis of ankylosing spondylitis (AS). Methods Enzyme-linked immuno sorbent assay (ELISA) was used to test the levels of plasma HMGB1 levels in 58 patients with active AS [bath ankylosing spondylitis disease activity index (BASDAI)>6, or 6>BASDAI>4 and erythrocyte sedimentation rate (ESR)>22 mm/1 h, 6> BASDAI>4 and hypersensitive C reactive protein (hsCRP)>9 mg/L], 73 cases of stable AS (BASDAI<4) and 70 healthy control. Twelve patients who were treated with TNF-alpha antagonist for 6 month were followed-up. Their plasma levels of HMGB1 were detected before and after treatment. Quantitative data were described by, while qualitative data were described by case number. Variance analysis or rank sum test was adopted for the difference between measurement data groups, LSD method was adopted for further pair-wise comparison. The correlation between variables was analyzed by using Spearman correlation analysis. Results The levels of plasma HMGB1, ESR, hsCRP, White blood cell WBC, GR, Mo and GLOB were significantly higher in the AS patients than those in the healthy control group (P 0.05). The plasma HMGB1 level, BASDAI, BAIFI, ESR, hsCRP and GLOB in the 12 followed-up patients were significantly decreased (P=0.034, 0.002, 0.002, 0.005, 0.004, 0.004) after being treated with biological agents for 6 months. Conclusion HMGB1 might play a vital role in the pathogenesis of ankylosing spondylitis,and the HMGB1 might be used as a clinical indicator to evaluate the activity of AS and to assess the clinical efficacy. Key words: Spondylitis, ankylosing; High mobility group box 1 protein; Inflammation; Activity; Therapy