Designer covalent heterobivalent inhibitors to prevent IgE-dependent allergic reactions

项目总结： 过敏反应是由过敏原介导的免疫球蛋白E(IgE)抗体的聚集引起的 肥大细胞表面，是启动全身反应的“关键事件”。过敏性疾病是 发达国家对健康的担忧日益加剧。根据过敏反应的严重程度，结果 可以从简单的瘙痒到过敏性休克，在美国每年导致1500人死亡。那里 过敏症无法治愈，目前的治疗方法侧重于急性症状或慢性免疫的治疗 压制。即使在限制饮食的情况下，食物过敏的意外接触也是非常频繁的， 有生命危险的过敏反应的患者。因此，需要更有效的替代疗法。 用于IgE介导的过敏反应。这项应用的目标是开发过敏原特异性IgE 以变应原结合IgE为靶点的抑制剂(cHBI：共价异二价抑制剂)，并防止它 识别过敏原。这种方法在特定靶向开始之前就抑制了过敏反应，但 没有广泛的免疫抑制。自然产生的过敏原在结构上通常是复杂的 具有多个过敏诱导表位的异源蛋白。从历史上看，要找出 个人过敏原表位对整体过敏反应的贡献。在之前的资助期间 周期，我们通过开发一个多组分的表位呈现平台解决了这个问题，我们 命名为纳米过敏原。利用纳米变应原筛选，我们可以研究个体变应原的免疫原性 表位，并确定免疫优势表位。利用鉴定的免疫优势表位，我们合成了 CHBI抑制剂，模拟表位并阻断识别特定表位的IgE抗体。这 方法阻止IgE在过敏原进入系统时识别它，并防止启动 过敏反应。我们最近已经证明，使用一种cHBI的鸡尾酒，我们可以阻止花生 在体外细胞脱颗粒方法中使用患者样本的过敏反应。在本申请中， 我们将使用人源化的小鼠模型在体内评估花生过敏抑制作用。同时，我们将 利用cHBI作为一个平台来阻止其他过敏原，包括贝类、尘螨和 榛子。所提出的工作具有创新性和重要意义，因为它(I)提供了一种新颖的分子设计 抑制“关键事件”引发过敏反应的方法具有潜在的长期临床应用价值 在食物、环境和药物过敏中，(2)它在没有任何非特异性免疫抑制的情况下这样做 系统组件，以及(Iii)开发一种急需的、生理上相关的、易于调节的和 可重复的平台(纳米变应原)，将用于识别免疫主导的公共变应原 表位及其在脱颗粒反应中的相对意义。最后，此应用程序具有很高的 潜在的影响，因为cHBI具有转移到临床的潜力。

Project Summary: Allergic reactions are elicited by the allergen-mediated-clustering of the immunoglobulin E (IgE) antibodies on the surface of mast cells, which is “the key event” in initiation of the systemic reaction. Allergic diseases are increasing health concerns in developed nations. Depending on the severity of the allergic reaction, the results can vary from a simple itch to anaphylactic shock, which results in 1,500 deaths each year in the US. There are no cures for allergies, and current therapies focus on treatment of acute symptoms or chronic immune suppression. Even with the most restricted diets, accidental exposure is very frequent for food allergies, putting patients at risk for life threatening anaphylaxis. Thus, there is a need for more effective, alternative treatments for IgE-mediated allergic responses. The objective of this application is to develop allergen-specific IgE inhibitors (cHBI: covalent heterobivalent inhibitor) that target allergen-binding IgE, and prevent it from recognizing the allergen. This approach inhibits the allergic reaction before it starts with specific targeting but without broad immune suppression. Naturally occurring allergens are typically complex, structurally heterogenous proteins with multiple allergy-inducing epitopes. Historically it has been a challenge to identify contributions from individual allergen epitopes to the overall allergic reaction. During the previous funding cycle, we addressed this problem by developing a multicomponent epitope presentation platform that we named nanoallergens. Using nanoallergen screening, we can study the immunogenicity of individual allergen epitopes, and identify immunodominant epitopes. Using the identified immunodominant epitope, we synthesize cHBI inhibitors that mimic the epitope and block the IgE antibodies that recognize the specific epitope. This method inhibits the IgE from recognizing the allergen when it enters the system and prevents the initiation of the allergic reaction. We have recently demonstrated that using a cocktail of cHBIs, we can block peanut allergic reactions using patient samples in an in vitro cellular degranulation method. In the current application, we will evaluate the peanut allergy inhibition in vivo using a humanized mice model. Simultaneously, we will exploit the potential of the cHBI as a platform to block other allergens including shellfish, dust mite and hazelnut. The proposed work is innovative and significant because it (i) offers a novel molecular design approach to inhibit “the key event” triggering an allergic response with potential long-term clinical applications in food, environmental and drug allergies, (ii) it does so without any non-specific suppression of immune system components, and (iii) develops a much needed, physiologically relevant, easily adjustable and reproducible platform (nanoallergens), which will be used in identifying immunodominant public allergen epitopes and their relative significance during degranulation responses. Lastly, this application has high potential impact because cHBI has the potential for translation to the clinic.