利用阻断IgG-FcγR结合短肽抑制ANCA诱导中性粒细胞活化研究  

Inhibitory effect of an small peptide that interferes with Fcγ-receptor recognition on antineutrophil cytoplasmic antibodies induced activity of neutrophils

作　　者：王湘玲[1] 陈楠[1] 俞海瑾[1] 任红[1] 王伟铭[1] 倪莉燕[1] 

机构地区：[1]上海交通大学附属瑞金医院肾脏科,200025

出　　处：《中华风湿病学杂志》2007年第5期267-270,I0001,共5页Chinese Journal of Rheumatology

基　　金：上海市重点学科基金(T0201);上海市卫生局重点学科基金(05111001);上海第二医科大学博士点建设基金(BXJ0507)

摘　　要：目的观察阻断IgG-FcγR相互作用的分支短肽tg19320对抗中性粒细胞胞质抗体（ANCA）所诱导中性粒细胞呼吸爆发的抑制作用，为探讨原发性小血管炎的新型治疗方向提供依据。方法人工合成短肽tg19320并鉴定其与人IgG的结合；玫瑰花环形成试验观察tg19320对IgG与FcγR相互作用的阻断效应。提纯活动期原发性小血管炎患者的ANCA IgG，间接免疫荧光联合抗原特异性ELISA鉴定ANCA。Ficoll-Paque密度梯度分离健康人中性粒细胞。以肿瘤坏死因子（TNF）-α（2ng／ml）预激粒细胞后以ANCA IgG（200μg／ml）刺激诱发其呼吸爆发，tg19320组以2．5mg/ml tg19320预处理粒细胞45min，中性粒细胞呼吸爆发以Ferri-cytochromere／uctionassay法检测。结果①tg19320与人IgG呈剂量依赖性的结合（P〈0．01）。②tg19320显著阻断IgG与FγR的相互作用（玫瑰花环形成率20．3％vs53．2％，P〈0．01），与人IgG组差异无统计学意义（20．3％vs 19．7％．P〉0．05）。③tg19320显著抑制ANCA所致中性粒细胞的呼吸爆发（1．83nomels／10^6 cells vss 12．99nmoles／10^6 cells，P〈0．01）。结论分支短肽tg19320体外可阻断ANCA所诱导的中性粒细胞活化。bjective Despite regular treatment, antineutrophil cytoplasmic antibodies （ANCA） associated systemic vasculitis （AASV）, in which the role of FcγRs has been established, are still associated with significant long-term mortality and remain an important cause of end-stage renal failure. ANCA plays an important role in the pathogenisis of primary systemic small vessel vasculitis （PSV） by their potential to activate neutrophils. Because the interaction between ANCA and its receptors on the Fc portion of immunoglobulins （FcγR） on neutrophils is essential in the activation process, we investigate the inhibitory effect of tg19320 on ANCA induced activation of neutrophils, which is a tetrameric tripeptide that interferes with IgG/Fcγ Rs interaction. Methods We prepared tgl9320 by solid-phase peptide synthesis. The binding between tg19320 and human IgG was assessed by enzyme-linked immunosorbent assay. The biological activity of tg19320 to intefere with FcFγ, receptor recognition was identified by rosette formation assay. ANCA IgG was prepared from the sera of active Wegener＇s granulomatosis （WG） and microscopic polyangiitis （MPA） patients. Neutrophils isolated from the blood of healthy volunteers were primed with TNF-α （2 ng/ml） and then incubated with ANCA IgG （200 μg/ml）, or pretreated with tg19320 （2.5 mg/ml） and then added with ANCA IgG. Superoxide burst of neutrophils was determined by Ferri-cytochrome reduction assay. Results We found that tg19320 bound tightly to human IgG in a dose dependent manner and the inhibition of the rosette formation between SRBC-IgG and U937 cells was statistically significant （20.3% vs 53.2%, P〈0.01）. The superoxide burst of primed neutrophils was suppressed markedly by tg19320 （1.83 nomels/10^6 cells vs 12.99 nmoles/10^6 cells, P〈0.01）. Conclusion The small peptide can intervene ANCA-induced activation of neutrophils, these results support the role of. FcγR in PSV pathogenesis and perhaps provide new approaches for the development

关 键 词：血管炎 抗体 抗中性粒细胞胞质 受体 IgG 短肽 

分 类 号：R593.27[医药卫生—内科学]