ADAMTS-13 metalloprotease abnormalities in systemic lupus erythematosus: is there a correlation with disease status?

To clarify the role of ADAMTS-13 in the pathogenesis of thrombotic microangiopathy in systemic lupus erythematosus (SLE) we evaluated ADAMTS-13 profile (metalloprotease antigen levels, anti-ADAMTS-13 autoantibody levels, activity) in distinct patient groups according to disease activity, extent of cumulative tissue damage and history of antiphospholipid syndrome or end-organ damage. Forty-one lupus patients were analysed. ADAMTS-13 metalloprotease antigen levels and anti-ADAMTS-13 autoantibodies were evaluated by ELISA. ADAMTS-13 activity was measured by Fluorescence resonance energy transfer (FRET) technique. ADAMTS-13 metalloprotease antigen levels were significantly decreased in patients with Systemic Lupus International Collaborative Clinics/American College of Rheumatology (SLICC/ACR) >1 (p