Epitope analysis of myeloperoxdase-specific anti-neutrophil

在血管炎中已检测到自身抗体、髓过氧化物酶特异性抗中性粒细胞胞浆抗体(MPO-ANCA)。然而，MPO-ANCA的滴度似乎并不总是反映疾病的活动性。这种明显的不一致可能主要归因于患者血清中MPO-ANCA对表位的不同识别。MPO-ANCA表位分析可以解释疾病活动性与MPO-ANCA产生的相关性。这些观察表明MPO-ANCA识别患者表面的MPO分子，具有特定表位的中性粒细胞通过FcRII刺激中性粒细胞。为了了解患者中性粒细胞的激活与疾病严重程度的关系，需要对MPO-ANCA的表位进行分析。已经建立了使用重组片段的自身抗体表位图，作为检测与MPO-ANCA相关疾病患者血清反应的小组。用一组重组MPO缺失突变体对MPO-ANCA相关性肾病和血管炎患者的血清进行了抗原表位分析，大部分血清与重链N-末端或C-末端发生反应，而没有血清与轻链反应。在肺纤维化、肺泡出血和急进性肾小球肾炎患者中，特定部位的反应性降低。此外，显示寡克隆性的表位图谱被分为两组和四组。其分布与疾病的临床特征有关。根据表位分类进行评分时，与这些临床特征的严重程度有关。进一步，我们分析了川崎病患者MPO-ANCA的表位。

Autoantibody, myeloperoxidase-specific anti-neutrophul cytoplasmic antibody (MPO-ANCA) has been detected in vasculitis. However, it appears that the titer of MPO-ANCA does not always reflect the activity of the disease. This apparent inconsistency may be mainly attributed to different epitope recognition by MPO-ANCA among sera of the patients. Epitope analysis of MPO-ANCA may explain the correlation between the disease activity and the production of MPO-ANCA.Moreover, mouse anti-MPO antibody induces superoxide production of neutrophils activated with TNFC? though FcRII.These observations suggest that MPO-ANCA recognizes MPO molecule on the surface of patients, neutrophils with specific epitope and stimulates them though FcRII.In order to understand the activation of neutrophils of the patients related with severity of the diseases, epitope of MPO-ANCA should be analyzed. Epitope mapping of autoantibodies using recombinant fragments have been established as a panel for examining reactivity with sera from patients of MPO-ANCA-related diseases. Epitope analysis of sera of patients with MPO-ANCA-related renal diseases and vasculitis was conducted by Western blotting and ELISA using a panel set of recombinant deletion mutants of MPO.Most of the sera reacted with either of the region of N- or C- terminus of the heavy chain, whereas no serum reacted with the light chain regions. The reactivity to the specific sites decreased in the serv of patients with pulmonary fibrosis, alveolar hemorrhage and rapidly progressive glomerulonephritis. Moreover, the epitope profiles showing the oligo-clonality were classified to two and four groups. The profiles had relation with clinical features of the diseases. When score was estimated by the classification of epitope, it was related with the severity of these clinical features. Further, we analyzed the epitopes of MPO-ANCA of patients with Kawasaki Disease.