Inhibition of oxidative activity of myeloperoxidase by anti-myeloperoxidase antibodies from patients with microscopic polyangiitis
- VernacularTitle:显微镜下型多血管炎患者血浆抗髓过氧化物酶抗体对髓过氧化物酶氧化活性的抑制作用
- Author:
Jie CHEN
;
Min CHEN
;
Zhangsuo LIU
;
Minghui ZHAO
- Publication Type:Journal Article
- Keywords:
Vasculitis;
Peroxidase;
Antibodies, antineutrop hilcytoplasmic;
Microscopy;
Ceruloplasmin
- From:
Journal of Peking University(Health Sciences)
2004;0(02):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the inhibitory effects on m yeloperoxidase (MP O) oxidation activity by affinity-purified anti-MPO antibodies from patients w it h microscopic polyangiitis (MPA) and to further investigate the interaction betw een MPO, ceruloplasmin and anti-MPO antibodies. Methods: Human IgG fractions wer e purified from plasma of 11 patients with anti-MPO antibody positive MPA and s e ra of 12 normal controls. Anti-MPO antibodies were further purified from anti- MP O antibody containing IgG fractions using MPO affinity chromatography. The enzym e activity of MPO was measured, in the presence of anti-MPO antibodies and norm a l IgG preparations, using a classical MPO oxidation assay. Interaction between c eruloplasmin, MPO and anti-MPO antibodies was further investigated using ELISA. Results: Anti-MPO antibodies from 7/11 patients with MPA could inhibit the MPO a ctivity as non-competitive inhibitors in a dose-dependent manner. Ceruloplasmi n could competitively inhibit the oxidation activity of MPO in a dose-dependent an d time-dependent manner. Anti-MPO antibodies could inhibit the binding between M PO and ceruloplasmin to a maximum of (75.4?11.6)%. Conclusion: Anti-MPO antibod ies, from the majority of patients with MPA, could inhibit the oxidation activity of MPO and interfere with the binding between MPO and ceruloplasmin.
