Exploiting and enhancing IgE-binding epitopes of the 2S albumins of peanuts and tree nuts

摘要： IgE介导的对花生（PN）和/或树坚果（TN）的食物过敏是美国人的主要健康问题。 在美国，大约4%的儿童和高达2%的成年人受到影响。共过敏 在这些食物中，相对常见的是，由于更常见的是， 发现共致敏。这些食物和口服药物的早期给药的最新进展 免疫疗法，尤其是与抗IgE联合使用具有优点。可惜这些 这些方法并非对所有患者都成功，即使成功，也有局限性 关于遵守和不可预测的突破。有大量未满足的需求， 1)了解IgE介导的过敏原激活肥大细胞的免疫学细节 了解TN之间和PN之间共同过敏的分子基础 和TN，3）开发改进的诊断方法，以识别临床相关的花生和坚果 过敏和4）设计新的方法来干扰花生引起的过敏反应。 该提案的总体概念是2S白蛋白是最重要的 花生和树坚果的过敏原，是了解PN和TN过敏的关键， 交叉反应性和开发有效的诊断和潜在的治疗试剂。 初步数据显示，我们已经1）开发了一种灵敏的ELISA测定法，2）鉴定了 IgE结合肽中的关键氨基酸，3）证明构象上 限制性（3D）肽强烈结合IgE，4）显示仅PN过敏的患者 和PN + TN变态反应在微阵列测定中鉴定不同的肽模式。我们 假设1）我们可以优化IgE与现有肽结合， 结合增强的肽，2）存在PN和选择性TN的交叉反应表位 和3）IgE与现有的和新的肽的结合将具有潜在的预测价值， 重要的临床结果。我们建议1）进行位置氨基酸（aa）筛选， 优化IgE与肽的结合，2）利用点击化学和钉合技术， 增强IgE结合和对蛋白酶的抗性，以及3）使用微阵列技术来评估 PN、WN、PecN、CN和PisN过敏患者明确定义样本的IgE结合 和那些正在进行临床试验的人。该项目的成功将建立一个新的 关于过敏原/IgE相互作用的知识框架，至少部分描述了 这些共同过敏的分子基础，设计新的诊断和推动我们沿着道路 开发一种口服的、基于肽的花生过敏治疗方法。

Abstract: IgE-mediated food allergy to peanuts (PN) and/or tree nuts (TN), is a major health problem in the United States, affecting approximately 4% of children and up to 2% of adults. Co-allergy among these foods is relatively common and is difficult to identify given the more common finding of co-sensitization. Recent progress with early administration of these foods and oral immunotherapy, especially in conjunction with anti-IgE have merit. Unfortunately, these approaches are not successful for all patients and, even when successful, have limitations regarding compliance and unpredictable breakthrough. There are significant, unmet needs to 1) understand the immunologic details of IgE mediated activation of mast cells by allergens from PN and TN, 2) understand the molecular basis for co-allergy among TN and between PN and TN, 3) develop improved diagnostics to identify clinically relevant peanut and tree nut allergy and 4) design new approaches to interfere with allergic reactions caused by peanuts. The overarching concept of this proposal is that the 2S albumins are the most important allergens of peanuts and tree nuts and are the key to understanding PN and TN allergy and cross-reactivity and to developing potent diagnostic and potentially therapeutic reagents. Preliminary data show that we have 1) developed a sensitive ELISA assay, 2) identified the critical amino acids within IgE-binding peptides, 3) demonstrated that conformationally constrained (3D) peptides bind IgE strongly and 4) shown that patients with PN allergy alone and PN + TN allergy identify different patterns of peptides in a microarray assay. We hypothesize that 1) we can optimize IgE binding to existing peptides and discover novel peptides with enhanced binding, 2) there are cross- reacting epitopes of PN and selected TN and 3) IgE binding to existing and novel peptides will have potential predictive value for important clinical outcomes. We propose to 1) perform positional amino acid (aa) screening to optimize binding of IgE to peptides, 2) utilize click chemistry and stapling technology to enhance IgE binding and resistance to proteases and 3) use microarray technology to assess IgE binding with well-defined samples from patients with PN, WN, PecN, CN and PisN allergy and from those undergoing clinical trials. Success in this project will establish a new intellectual framework regarding allergen/IgE interactions, describe, at least in part, the molecular basis for these co-allergies, design new diagnostics and move us along the path toward development of an oral, peptide based, treatment for peanut allergy.