Autoantibody and Biopsy Grading Are Associated with Expression of ICAM-1, MMP-3, and TRAIL in Salivary Gland Mononuclear Cells of Chinese Patients with Sjögren’s Syndrome

Abstract

Objective.Sjögren’s syndrome (SS) is an inflammatory autoimmune disease. We investigated important factors associated with the expression of inflammation-related molecules in minor salivary gland (MSG) mononuclear cells in patients with SS.Methods.Thirty-four patients with SS with a MSG biopsy grading of either grade III (10 patients) or grade IV (24 patients) were enrolled. The age, sex, autoantibodies, cell infiltration, and intercellular adhesion molecule-1 (ICAM-1), matrix metalloproteinase-3 (MMP-3), tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), or CXCR3 expression were also analyzed.Results.Ten of the 34 patients with SS were diagnosed with secondary SS; in these patients, the diagnosis of rheumatoid arthritis was confirmed in 8 and systemic lupus erythematosus in 2. TRAIL and ICAM-1 were overexpressed in patients with antinuclear antibodies (ANA) > 1:160, compared to those with titer < 1:160 (45.1 ± 4.4 vs 41.2 ± 3.9, p = 0.021, and 15.2 ± 5.7 vs 10.8 ± 3.3, p = 0.018, respectively). Higher erythrocyte sedimentation rate (ESR; ≥ 20) was associated with higher TRAIL expression and CD20 cell infiltration in contrast to lower ESR (< 20; p < 0.05). ICAM-1, TRAIL, and MMP-3 were expressed more predominantly in anti-SSA-positive than in anti-SSA-negative patients with SS. There was a significant difference in CD20 cell infiltration and MMP-3 expression between primary SS and secondary SS. Biopsy of a grade IV showed a significantly increased expression of TRAIL (44.9 ± 4.5 vs 40.8 ± 3.6, p = 0.013) and MMP-3 (62.7 ± 6.3 vs 54.4 ± 7.3, p = 0.003) in mononuclear cells as compared to those of grade III.Conclusion.In our study, pathologic grading with a higher grade (grade IV) and the presence of SSA or a higher titer of ANA were significantly associated with the overexpression of TRAIL, MMP-3, or ICAM-1 in the salivary gland mononuclear cells in patients with SS.