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

摘要： 免疫球蛋白介导的食物过敏，花生(PN)和/或坚果(TN)，是一个主要的健康问题 在美国，大约4%的儿童和多达2%的成年人受到影响。共同变态反应 在这些食物中相对常见，很难识别，因为更常见的是 发现共敏化。早期应用这些食物和口服药物的最新进展 免疫治疗，特别是联合抗-IgE治疗有一定的优点。不幸的是，这些 方法并不是对所有患者都成功的，即使成功了，也有局限性。 关于合规和不可预测的突破。有重大的、未得到满足的需求 1)了解IgE介导的过敏原激活肥大细胞的免疫学细节 从PN和TN，2)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上相关的花生和坚果 过敏和4)设计新的方法来干扰花生引起的过敏反应。 这项建议的首要概念是2S白蛋白是最重要的 花生和坚果的过敏原，是了解PN和TN过敏和 交叉反应和开发有效的诊断和潜在的治疗试剂。 初步数据表明，我们已经开发出一种灵敏的ELISA法，2)鉴定了 Ig E结合肽中的关键氨基酸，3)证明了构象 限制性(3D)肽与IgE强烈结合，4)显示仅有PN过敏的患者 和PN+TN过敏在微阵列检测中识别不同模式的多肽。我们 假设1)我们可以优化IgE与现有多肽的结合并发现新的 具有增强结合的多肽，2)存在Pn和所选Tn的交叉反应表位 3)与现有的和新的多肽结合的IgE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)筛查 优化IgE与多肽的结合，2)利用点击化学和装订技术 增强IgE结合和对蛋白酶的抵抗力；3)使用微阵列技术评估 与PN、WN、PecN、CN和PisN过敏患者明确的样本的Ige结合 以及那些正在进行临床试验的人。这个项目的成功将建立一个新的 关于过敏原/IgE相互作用的智力框架，至少部分描述了 这些共同过敏的分子基础，设计新的诊断方法，推动我们前进 开发一种以多肽为基础的口服花生过敏疗法。

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.