Natural and disease associated anti-myeloperoxidase (MPO) autoantibodies

作者：Guilpain Philippe; Servettaz Amelie; Batteux Frederic; Guillevin Loic; Mouthon Luc^*

来源：Autoimmunity Reviews, 2008, 7(6): 421-425.

DOI：10.1016/j.autrev.2008.03.009

• microscopic polyangiitis
• natural autoantibodies
• myeloperoxidase
• ANCA
• reactive oxygen species

Myeloperoxidase (MPO) is a cationic; protein present in primary azurophilic; granules of neutrophils and monocytes. MPO produces a highly deleterious reactive oxygen species, the hypochlorous acid (HOCl), using hydrogen peroxide (H2O2) and chloride ions as substrate. Anti-MPO antibodies (Abs) are present in 70% of the cases in patients with microscopic polyangiitis (MPA), a small-sized vessel vasculitis. Anti-MPO Abs from patients with MPA can trigger the release of MPO by neutrophils and monocytes. Anti-MPO Abs can activate MPO to generate an oxidative stress deleterious for the endothelium. Thus, we recently demonstrated that MPA sera with anti-MPO Abs activated MPO in vitro, and generated hypochlorous acid, whereas sera from MPA patients with no anti-MPO Abs or healthy individuals did not. Both hypochlorous acid production and endothelial lysis were abrogated by N-acetylcysteine (NAC), an antioxidant molecule. Thus, anti-MPO Abs could play a pathogenic role in vivo by triggering an oxidative burst leading to severe endothelial damages.

• 出版日期2008-6