Osteopontin in systemic lupus erythematosus

Abstract

  In systemic lupus erythematosus (SLE), lupus nephritis (LN) is an important complication as an intractable condition and considered to be a prognostic factor. Based on the past reports that explain immunological functions of OPN and its relationship with autoimmune diseases such as LN or IgA nephropathy, we measured OPN full and OPN N-half in serum and urine of SLE patients and examined the possibility as a disease biomarker. OPN N-half is known as a more physiologically active form than OPN full. As a result, OPN N-half in urine was higher in LN than in healthy control, and also higher than in diabetic nephropathy that is a non-inflammatory nephropathy. In addition, OPN N-half in urine decreased after the treatment of LN, suggesting that OPN N-half in urine could be a biomarker for evaluating disease activity of LN.