Juan Li1, Lemei An, Zhuoli Zhang. 1. Rheumatology and Clinical Immunology Department, Peking University First Hospital, Beijing, China; Renal Department, General Hospital of Tisco, Shanxi, China. xiaodaizi.521@163.com.
Abstract
OBJECTIVES: To evaluate the roles of complement activation products C3d and C4d binding to lymphocytes in the diagnosis of systemic lupus erythematosus (SLE) in a Chinese cohort of patients. METHODS: 96 patients with SLE, 44 patients with other autoimmune disease and 40 healthy control individuals were enrolled in this study. The levels of C3d and C4d binding to peripheral CD4+ T and CD19+ B lymphocyts (designated as T-C3d, T-C4d, B-C3d, B-C4d ) was assessed by flow cytometry. The diagnostic values of these biomarkers were determined by receiver-operator characteristic analysis. RESULTS: The levels of T-C3d, T-C4d, B-C3d, B-C4d were significantly higher in SLE patients than patients with other disease and healthy controls (p<0.01). As diagnostic tools, T-C4d and B-C4d were 61.1% sensitive/94.3% specific and 63.9% sensitive/94.3% specific in differentiating SLE patients from patients with other disease and healthy controls, respectively. T-C4d and B-C4d were significantly associated with SLE disease activity as measured by the SLE disease activity index (SLEDAI) (p<0.001), low serum C3 (p<0.001), low serum C4 (p=0.006), anti-dsDNA (IIF) (p=0.001), and anti-dsDNA (ELISA) (p=0.001). CONCLUSIONS: Complement activation products C3d and C4d binding to lymphocytes can reflect the disease activity of SLE and can be used as biomarkers for SLE.
OBJECTIVES: To evaluate the roles of complement activation products C3d and C4d binding to lymphocytes in the diagnosis of systemic lupus erythematosus (SLE) in a Chinese cohort of patients. METHODS: 96 patients with SLE, 44 patients with other autoimmune disease and 40 healthy control individuals were enrolled in this study. The levels of C3d and C4d binding to peripheral CD4+ T and CD19+ B lymphocyts (designated as T-C3d, T-C4d, B-C3d, B-C4d ) was assessed by flow cytometry. The diagnostic values of these biomarkers were determined by receiver-operator characteristic analysis. RESULTS: The levels of T-C3d, T-C4d, B-C3d, B-C4d were significantly higher in SLEpatients than patients with other disease and healthy controls (p<0.01). As diagnostic tools, T-C4d and B-C4d were 61.1% sensitive/94.3% specific and 63.9% sensitive/94.3% specific in differentiating SLEpatients from patients with other disease and healthy controls, respectively. T-C4d and B-C4d were significantly associated with SLE disease activity as measured by the SLE disease activity index (SLEDAI) (p<0.001), low serum C3 (p<0.001), low serum C4 (p=0.006), anti-dsDNA (IIF) (p=0.001), and anti-dsDNA (ELISA) (p=0.001). CONCLUSIONS: Complement activation products C3d and C4d binding to lymphocytes can reflect the disease activity of SLE and can be used as biomarkers for SLE.