Mapping the Critical Epitopes of Ara h 2 and Ara h 6

绘制 Ara h 2 和 Ara h 6 的关键表位

基本信息

批准号：
8699138
负责人：
STEPHEN C DRESKIN
金额：
$ 39.04万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-08-23 至 2016-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8699138
关键词：
Accounting Address Affect Affinity Albumins Allergen Immunotherapy Allergens Allergic Allergic Reaction Allergy to peanuts Amino Acids Anaphylaxis Antibodies Basophils Binding Biological Assay Biological Markers Cells Clinical Complex Cysteine Data Development Diagnosis Diagnostic Reagent Epitopes Escherichia coli Evaluation Food Future Health Hospitals Human Hypersensitivity IgE IgE Receptors Immunoglobulin G Immunotherapy In Vitro Ingestion Investigational Therapies Lead Libraries Maps Measures Mediating Methods Modeling Molecular Monoclonal Antibodies Mus Mutation Natural History Oral Oryctolagus cuniculus Outcome Patients Pattern Peanuts - dietary Peptides Pichia Population Prevalence Reaction Reagent Recombinant Antibody Recombinants Recording of previous events Relative Risks Research Risk Assessment Safety Severities Structure Technology United States base clinical practice clinically relevant crosslink design human monoclonal antibodies improved in vivo inhibitor/antagonist mast cell neutralizing antibody novel diagnostics novel therapeutics oral immunotherapy research study response tool

项目摘要

DESCRIPTION (provided by applicant): Hypersensitivity to foods is a world-wide problem in the industrialized world and its prevalence appears to be increasing, affecting approximately 1% of the US population. IgE-mediated reactions to foods, particularly peanuts, are the most common cause of anaphylaxis occurring outside of the hospital. Avoidance of peanuts, the recommended approach, is inadequate due to frequent accidental ingestion. There are a number of emerging experimental therapies but these all have limitations. Although we understand a great deal about how IgE binds to peanut allergens, little is known about how these allergens cross-link IgE/IgE receptor complexes (IgE/FceRI) to activate mast cells and basophils. This proposal will capitalize on three significant findings from our group: 1) the related and complementary 2S albumins, Ara h 2 and Ara h 6, are the most potent peanut allergens, 2) binding of IgE to two specific linear epitopes (one on each allergen) is associated with more severe clinical histories and 3) recombinant Ara h 6 expressed in Pichia pastoris, but not in Escherichia coli, has full effector activity making this a robust model for understanding th molecular basis of effector function. In the proposed studies we will measure binding of patient-derived IgE to specific linear epitopes of Ara h 2 and Ara h 6 in three important clinical settings natural history of clinical reactivity, response of patients to clinically indicated peanut challenes, and response of patients to oral immunotherapy (OIT). We will use these data to determine the relative risk of having defined binding patterns to peptides of Ara h 2 and Ara h 6 in each of these clinical settings. We will then determine the specific amino acids of Ara h 6 and then Ara h 2 that are critical for effective cross-linking of IgE/Fc?RI. Finally we will develop rabbit polyclnal antibodies, murine monoclonal antibodies, and human scFv fragments as potential inhibitors of Ara h 2 and Ara h 6 - mediated cross-linking of IgE/Fc?RI. These will also be useful as novel diagnostic reagents. By completing these specific aims we will overcome the significant obstacle of understanding how allergens interact with IgE to cross-link IgE/FceRI complexes and will move the field forward towards development of new diagnostic and therapeutic tools for the evaluation and treatment of peanut allergy. The future direction of this research is to fully develop these tools and bring them to clinical practice.

描述（由申请人提供）：对食品的超敏反应是工业化世界的一个世界问题，其流行率似乎正在增加，影响了美国人口的1％。 IgE介导的对食物，尤其是花生的反应是医院外发生过敏反应的最常见原因。由于经常意外摄入，避免花生的方法是建议的方法不足。有许多新兴的实验疗法，但都有局限性。尽管我们了解IgE如何与花生过敏原结合，但对于这些过敏原如何交叉链接IgE/IgE受体复合物（IgE/FCERI）如何激活肥大细胞和嗜碱性粒细胞，知之甚少。 This proposal will capitalize on three significant findings from our group: 1) the related and complementary 2S albumins, Ara h 2 and Ara h 6, are the most potent peanut allergens, 2) binding of IgE to two specific linear epitopes (one on each allergen) is associated with more severe clinical histories and 3) recombinant Ara h 6 expressed in Pichia pastoris, but not in Escherichia coli, has full效应子活性使其成为理解效应子函数的分子基础的强大模型。在拟议的研究中，我们将在三种重要的临床反应性的自然临床环境中测量患者衍生的IgE与ARA H 2和ARA H 6的特定线性表位的结合，患者对临床表明的花生挑战的反应以及患者对口服免疫治疗（OIT）的反应。我们将使用这些数据来确定在这些临床环境中的每一个中都定义了与Ara H 2和Ara H 6肽的结合模式的相对风险。然后，我们将确定ARA H 6的特异性氨基酸，然后确定对于有效的IgE/FC？RI的交联至关重要的ARA H 2。最后，我们将开发兔多胞菌抗体，鼠单克隆抗体和人类SCFV片段，作为ARA H 2和ARA H 6-介导的IgE/Fc？ri的介导的交联的潜在抑制剂。这些也将作为新型诊断试剂有用。通过完成这些具体目标，我们将克服了解过敏原如何与IgE相互作用的重大障碍，以交叉IgE/FCERI络合物，并将该领域向前发展，以开发新的诊断和治疗工具，以评估和治疗花生过敏。这项研究的未来方向是充分开发这些工具并将其带入临床实践。