Serum Complement Protein C3a Level is Associated With Anti dsDNA Ab in Systemic Lupus Erythematosus: a Brief Report

Objective. Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that is characterized by complement dysfunction and a wide range of autoantibody production. However, data about the relation between C3a and anti-ds DNA Ab in SLE are scarce. Methods.Thirteen SLE patients, diagnosed on the basis of SLICC classification criteria (6 patients positive for anti-Sm Ab, 7 patients positive for anti-dsDNA Ab) were enrolled in the present study. Serum levels of C3a, C1q were quantified by Western Blotting. Clinical, biochemical, serological and other markers of disease activity (anti-SM, anti-dsDNA) were measured by standard laboratory procedure.Results.Serum C3a levels were significantly higher in anti-dsDNA Ab (+) patients compared to anti-Sm Ab (+) patients (p < 0.01). And serum C3a levels positively correlated with SLE Disease Activity Index (SLEDAI) (p < 0.05, r = 0.6134). Interestingly, C3a was slightly correlated positively with D-Dimer, but no significant difference was found (p = 0.0983, r = 0.4783).Conclusion.C3a level is relative to SLE disease activity and may be a promising biomarker for monitoring thrombophilia in SLE.