HMGB1 concentrations in sera from SLE patients and healthy controls (HC). A) Serum HMGB1 levels in SLE patients and HC using ELISA. Horizontal lines represent the median. B) Serum HMGB1 levels of SLE patients and HC measured by Western blot. C) HMGB1 levels measured by Western blot in active patients with renal manifestations and with those without renal manifestations.