IL-18 levels in SLE patients were positively related to disease activity, erythrocyte sedimentation rate (ESR), protein/creatinine ratio, anti-dsDNA titers, and endothelial progenitor cell (EPC)/circulating angiogenic cell (CAC) dysfunction and were negatively related to creatinine clearance and C3 expression (58–60, 62, 63). Here, C3 is linked to systemic lupus erythematosus.