Serum TWEAK as a biomarker for disease activity of systemic lupus erythematosus.

Abstract

This study aimed to identify serum and urine biomarkers that correlate with disease activity in female patients with systemic lupus erythematosus (SLE). Serum and urine levels of interferon γ-induced protein-10 (IP-10), TNF-like weak inducer of apoptosis (TWEAK), and monocyte chemotactic protein-1 (MCP-1) of 70 patients with SLE and 61 healthy controls were measured with enzyme-linked immunosorbent assays. The serum and urine levels of TWEAK, IP-10, and MCP-1 in both high and low SLE disease activity index (SLEDAI) groups of SLE patients were markedly higher compared with those of healthy controls. Moreover, the serum TWEAK level was positively correlated with the serum IP and serum MCP-1 levels (p<0.001 for both). The serum TWEAK levels, SLEDAI scores, and urine protein/creatinine levels were significantly different between the SLE group with non-renal involvement and with renal involvement (p=0.034, p<0.001, and p<0.001, respectively). The serum TWEAK level was a crucial determinant for a high SLEDAI score and renal involvement (p=0.044 and p=0.046, respectively). Serum TWEAK might be a serologic biomarker candidate that reflects disease activity and renal involvement in patients with SLE.