The role of peroxidasin in Goodpasture's disease

过氧化物酶在古德帕斯彻氏病中的作用

• 批准号: 8594875
• 负责人: Abraham Scott McCall
• 金额: $ 2.98万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8594875
• 关键词: Achievement; Affect; Affinity Chromatography; Anabolism; Antibodies; Appearance; Autoantibodies; Autoantigens; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Basement membrane; Binding; Biochemical; Biological Assay; Cell Culture Techniques; Cessation of life; Characteristics; Clinical; Collaborations; Collagen Type IV; Complex; Data; Department of Defense; Disease; Early Diagnosis; Enzymes; Epitope Mapping; Glomerular basement membrane antibody; Hydrogen Peroxide; Immunization; Interferometry; Kinetics; Lead; Letters; Link; Lung; Mass Spectrum Analysis; Mission; Modeling; Nature; Normal tissue morphology; Nucleotides; Oxidants; Oxidative Stress; PRTN3 gene; Pathogenesis; Patients; Peptide Fragments; Peroxidases; Physiological; Pilot Projects; Play; Proteolysis; Public Health; Research; Resolution; Role; Sampling; Serum; Source; Specificity; Techniques; Testing; Time; Tissues; Work; base; chemical bond; cofactor; crosslink; domain mapping; eosinophil peroxidase; extracellular; glomerular basement membrane; grasp; human disease; hypobromous acid; in vivo; inhibiting antibody; insight; meetings; novel; oxidation; peroxidasin; prevent; public health relevance; repository; tissue culture

DESCRIPTION (provided by applicant): Goodpasture's (GP) disease is an autoimmune disorder which affects the glomerular basement membrane (GBM) and pulmonary vasculature resulting in death for 50% of cases. In GP disease, antibodies specifically target the non-collagenous 1 (NC1) domain of the ¿3 and 5 chains of the collagen IV network. The NC1 domain occurs as hexamers that are covalently crosslinked by a sulfilimine chemical bond (-S=N-), which renders the NC1 hexamer inert to binding of GP autoantibodies. This bond is formed by the recently identified enzyme peroxidasin (PXDN) which putatively utilizes hydrogen peroxide as an initial oxidant to form hypobromous acid (HOBr) as the terminal oxidant for S=N bond formation. The highly reactive nature of HOBr suggests that peroxidasin complexes with the NC1 domain in vivo to maximize the potential efficiency of S=N bond formation and decrease collateral oxidative stress on the surrounding tissue. The pathogenesis of Goodpasture's disease may involve the disruption of PXDN function and normal cross-linking which would lead to proteolysis and self-immunization with auto-antigenic peptide fragments. The objective of this particular proposal is to determine peroxidasin's role in the pathogenesis of Goodpasture's disease. My pilot data has revealed novel anti-PXDN antibodies in GP patients which inhibit S=N bond formation. Additionally, I have found that PXDN can form the S=N bond using nucleotide monophosphates for oxidation rather than hydrogen peroxide (H2O2). These findings lead to the central hypothesis that anti-peroxidasin antibodies play a key role in the pathogenesis of GP disease by preventing the formation of the sulfilimine bond. This hypothesis will be interrogated with three specific aims: Aim 1: To characterize anti-peroxidasin antibodies in Goodpasture's patients. I have identified Goodpasture's patients who have anti-peroxidasin antibodies. We hypothesize that anti-peroxidasin antibodies target the peroxidase domain and inactivate S=N bond forming activity. Aim 2: To determine the time course of appearance and binding characteristics of anti-peroxidasin antibodies in Goodpasture's disease patients. Serial serum samples from 30 patients before the appearance of Goodpasture's disease will give temporal resolution to anti-PXDN antibodies. We hypothesize that anti-peroxidasin antibodies play a causal role in Goodpasture's disease. Aim 3: To identify the initial oxidant source used to form the S=N bond by peroxidasin. Hydrogen peroxide is the putative oxidant for peroxidasin but preliminary data shows that PXDN is capable of using nucleotide monophosphates as the initial oxidant for S=N bond formation. We hypothesize peroxidasin uses O2 and extracellular nucleotides as initial oxidants to form HOBr for the biosynthesis of the S=N bond. The achievement of these aims will provide insight into a novel mechanism of autoimmune disease pathogenesis and potentially enable early diagnosis of GP disease through understanding the inhibition of an unprecedented enzymatic mechanism in tissue biosynthesis.

描述（由应用提供）：Goodpasture的（GP）疾病是一种自身免疫性疾病，影响肾小球基底膜（GBM）和肺脉管系统，导致50％的病例死亡。在GP疾病中，抗体专门针对胶原蛋白IV网络的3和5链的非胶原1（NC1）结构域。 NC1结构域是由硫亚胺化学键（-s = n-）共价交联的六聚体，这将NC1六聚体惰性与GP自身抗体的结合。该键是由最近鉴定出的过氧化物素（PXDN）形成的，该酶将过氧化氢用作初始氧化剂，形成低透明酸（HOBR）作为S = N键形成的末端氧化剂。 HOBR的高反应性质表明，在体内的过氧化物素复合物与NC1结构域具有最大化S = N键形成的潜在效率，并减少周围组织中的附带氧化物应激的潜在效率。 Goodpasture病的发病机理可能涉及PXDN功能和正常交联的破坏，这将导致蛋白水解和自身 - 抗原肽片段的自我免疫。该特定建议的目的是确定过氧化物素在发病机理中的作用 Goodpasture病。我的试点数据显示，GP患者的新型抗PXDN抗体抑制了S = N键的形成。此外，我发现PXDN可以使用核二磷酸盐而不是过氧化氢（H2O2）形成S = N键。这些发现导致了一个核心假设，即抗过敏素抗体通过防止硫亚胺键的形成在GP疾病的发病机理中起关键作用。该假设将通过三个特定的目的进行审问：目标1：表征Goodpasture患者中抗氧化毒素抗体的表征。我已经确定了具有抗过敏素抗体的Goodpasture患者。我们假设抗过氧化物素抗体靶向过氧化物酶结构域并灭活S = N键形成活性。目的2：确定Goodpasture病患者中抗过敏素抗体的外观和结合特征的时间过程。在出现Goodpasture病之前，来自30名患者的系列血清样品将暂时解决抗PXDN抗体。我们假设抗过敏性抗体在Goodpasture病中起因果作用。目标3：确定通过过氧化物素形成S = N键的初始氧化物源。过氧化氢是过氧化物素的推定氧化物，但初步数据表明，PXDN能够将核二磷酸核二磷酸作为S = N键形成的初始氧化物。我们假设过氧化物素使用O2和细胞外核唯一作为初始氧化物，以形成hobr，以用于S = N键的生物合成。这些目标的实现将洞悉一种新型的自身免疫性疾病发病机理的机制，并通过了解抑制组织生物合成中前所未有的酶促机制，从而有可能早期诊断GP疾病。