Basophil phenotype & activation in peanut allergy and oral Immunotherapy

项目摘要(见说明)：花生过敏(PA)是一种潜在的致命疾病，需要改进诊断、临床监测和治疗方法。嗜碱性粒细胞是最不常见的血粒细胞，已被认为是PA和花生过敏反应的重要致病因素。某些细胞表面的表型特征可以帮助识别体内或体外被过敏机制激活的嗜碱性粒细胞。在这个项目中，我们试图确定嗜碱性粒细胞的表型和功能是否可以作为预测个体PA患者对花生的临床反应性的方法的一部分，以提高口服免疫疗法(OIT)治疗PA的安全性和有效性，和/或为每个花生过敏患者定制OIT方案。在这个项目的目标1中，我们将使用详细的免疫表型方法来监测患有PA的儿童和成人受试者外周血中嗜碱性粒细胞的表型和激活状态，在他们参加OIT针对PA的第二阶段临床试验(本U19申请的项目1)之前的基线测量，以及在OIT过程中的多个间隔。本研究将验证PA患者外周血嗜碱性粒细胞中活化和细胞表面标志物的表达与OIT前和OIT期间对花生变应原的急性临床反应性相关的假设，并可用于监测OIT诱导的耐受性的发展、成功和持久性。在目标2中，我们将进行人嗜碱粒细胞表型和功能的体外研究(即嗜碱粒细胞激活试验[BATS])，以衡量这些嗜碱性细胞在体外对攻击性(花生)变应原与无关变应原的反应。这项工作将检验一种假设，即花生变应原诱导PA患者嗜碱性粒细胞表型(例如CD20Sc的表面表达)或功能(例如介质的分泌)的变化幅度与OIT过程中花生变应原敏感性的临床证据减少相关。我们在这项工作中的主要目标之一是开发创新、快速和可靠的方法来监测嗜碱性粒细胞的表型和功能，这些方法可以用于临床，如预测受试者对花生的临床敏感性，预测OIT的临床结果，为个别受试者定制最佳的OIT方案，和/或监测OIT的发展、有效性或持久性。

PROJECT SUMMARY (See instructions): Peanut allergy (PA) is a potentially fatal disorder In need of improved methods for diagnosis, clinical monitoring, and treatment. Basophils, the least common blood granulocyte, have been implicated as Important contributors to the pathology of PA and peanut-induced anaphylaxis. Certain cell surface phenotypic features can help to Identify basophils which have been activated by allergic mechanisms in vivo or in vitro. In this project, we seek to determine whether the phenotype and function of blood basophils can be used as part of an approach to predict the severity of clinical reactivity to peanut In individual subjects with PA, to improve the safety and efficacy of an oral Immunotherapy (OIT) protocol to treat PA, and/or to customize the OIT protocol to each individual peanut allergic subject. In Aim 1 of this project, we will employ detailed immuophenotyping approaches to monitor the phenotype and activation status of basophils in the peripheral blood of pediatric and adult subjects with PA, as measured at baseline before their enrollment in a phase 2 clinical trial of OIT for PA (Project 1 of this U19 application) and at multiple intervals during the course of OIT. This work will test the hypothesis that the expression of activation and cell surface markers in the blood basophils of PA patients correlates with their acute clinical reactivity to peanut allergen before and during OIT and can be used to monitor the development, success, and durability of tolerance induced by OIT. In Aim 2, we will perform in vitro studies of human basophil phenotype and function (i.e., basophil activation tests [BATs]), to measure the responses of such basophils to challenge with offending (peanut) vs. irrelevant allergens ex vivo. This work will test the hypothesis that the magnitude of peanut allergen-induced changes in the phenotype (e.g., surface expression ofCD20Sc) or function (e.g., secretion of mediators) of blood basophils of PA patients correlates with the reduction in clinical evidence of peanut allergen sensitivity over the course of OIT. One of our key goals in this work is to develop innovative, rapid, and reliable methods to monitor basophil phenotype and function that can be used clinically for such purposes as predicting a subject's clinical sensitivity to peanut, predicting the clinical outcome of OIT, customizing the OIT protocol optimally for individual subjects, and/or monitoring the development, effectiveness, or durability of OIT.