Humoral mechanisms of tolerance in peanut oral immunotherapy

 描述（由申请人提供）： 候选人：Sarita Patil，医学博士是马萨诸塞州总医院 (MGH) 过敏和免疫学的专职医师，也是哈佛医学院 (HMS) 医学讲师的初级研究员。在她的研究期间，她进行了转化研究，开发了一种荧光过敏原特异性 B 细胞四聚体，可以成功识别接受免疫治疗的花生过敏患者外周的花生特异性 B 细胞。基于该技术，K23 应用旨在了解体液反应在口服食物免疫治疗中的作用，特别是在克隆水平上研究花生过敏原 Ara h 2 的免疫球蛋白反应，从而更深入地了解人类食物过敏患者的免疫治疗机制。拟议的项目结合了临床试验、基础科学和生物信息学的研究，以开发转化研究方面的独特专业知识。本提案中概述的工作、培训活动和指导计划将成功为 Patil 博士提供首次 R01 申请以及作为一名医师科学家的独立职业。指导、培训活动和环境：Patil 博士将在韦恩·施莱弗勒 (Wayne Shreffler) 博士的指导下在 MGH 免疫学和炎症疾病中心 (CIID) 以及在 J. Christopher Love 博士的共同指导下在麻省理工学院 (MIT) 执行拟议项目。 CIID 是一个多学科基础科学中心，是麻省总医院免疫学研究的基础。此外，麻省总医院的 Robert Anthony 博士和耶鲁大学医学院的 Steven Kleinstein 博士将在 Patil 博士的咨询委员会中任职，分别提供过敏性疾病中免疫球蛋白糖基化以及使用计算生物学方法进行免疫球蛋白谱分析的专业知识。为了补充她提出的项目和导师的专业知识，帕蒂尔博士将通过哈佛公共卫生学院和哈佛催化剂完成转化研究、统计学、测序、蛋白质组学和生物信息学方面的教学课程。帕蒂尔博士拥有的合作机会、智力环境和资源都非常出色。研究：IgE 介导的花生过敏对公共健康构成重大风险，因为微小的花生暴露就可能引起严重的过敏反应。对儿童进行花生口服免疫疗法（PNOIT）的临床试验，在仔细观察下逐渐增加花生暴露量，已成功诱导脱敏；然而，这些儿童中只有一小部分具有长期耐受性。接受 PNOIT 的患者的花生特异性 IgE 水平通常会降低，而花生特异性 IgG 和 IgG4 水平会逐渐升高，但花生特异性免疫球蛋白的这些变化对长期耐受的机制贡献仍不清楚。 该项目探讨 PNOIT 如何影响 B 细胞库以及这些变化如何与预期的异质临床结果相关。我们假设 PNOIT 后的持久临床耐受性与高亲和力和寡克隆过敏原特异性功能抗体的诱导直接相关，并且部分归因于诱导。使用基于荧光四聚体的方法来识别过敏原特异性 B 细胞，我们希望识别临床预后标志物，并提高我们对免疫治疗机制的理解，特别是抗体的病理生理作用及其作为耐受性和治疗剂生物标志物的潜力。 为此，我们建议在 PNOIT 患者中使用蛋白质组学和新一代测序来绘制过敏原特异性 B 细胞库。我们还提出对来自过敏原特异性 B 细胞的重组抗体进行功能研究，以探索 PNOIT 耐受的潜在机制。通过研究在 PNOIT 期间产生不同耐受性的花生过敏患者以及自然不再过敏的花生过敏患者，我们希望阐明 B 细胞库对诱导花生过敏长期耐受的贡献。这些努力可能有助于确定相关的临床生物标志物和潜在的治疗途径，以改进 PNOIT 治疗花生过敏的效果。

 DESCRIPTION (provided by applicant): Candidate: Sarita Patil, MD is a staff physician in Allergy and Immunology at Massachusetts General Hospital (MGH) and a junior investigator as an Instructor in Medicine at Harvard Medical School (HMS). During her fellowship, she conducted translational research, which led to the development of a fluorescent allergen- specific B cell tetramer that could successfully identify peanut-specific B cells in the periphery f peanut- allergic patients undergoing immunotherapy. Building on that technology, this K23 application aims to understand the role of the humoral response in oral food immunotherapy, specifically investigating the immunoglobulin response to the peanut allergen Ara h 2 on a clonal level, allowing for greater insight into mechanisms of immunotherapy in human patients with food allergy. The proposed project combines research in clinical trials, basic science, and bioinformatics to develop a unique expertise in translational research. The work, training activities, and mentoring plan outlined in this proposal will successfully position Dr. Patil for hr first R01 application and an independent career as a physician-scientist. Mentorship, Training Activities, and Environment: Dr. Patil will perform the proposed project in the Center for Immunology and Inflammatory Diseases (CIID) at MGH under the mentorship of Dr. Wayne Shreffler and at Massachusetts Institute of Technology (MIT) under the co-mentorship of Dr. J. Christopher Love. The CIID is a multidisciplinary basic science center that serves as the foundation of immunology research at MGH. In addition, Dr. Robert Anthony at MGH and Dr. Steven Kleinstein at Yale School of Medicine will serve on Dr. Patil's Advisory Committee to provide expertise on immunoglobulin glycosylation in allergic diseases as well as immunoglobulin repertoire analysis using computational biology approaches, respectively. To complement her proposed projects and the expertise of her mentors, Dr. Patil will complete didactic courses in translational research, statistics, sequencing, proteomics, and bioinformatics through the Harvard School of Public Health and the Harvard Catalyst. The collaborative opportunities, intellectual environment and resources available to Dr. Patil are outstanding. Research: IgE-mediated peanut allergy poses a significant public health risk, as minute peanut exposures can cause severe allergic reactions. Clinical trials of peanut oral immunotherapy (PNOIT) with gradual incremental peanut exposure under careful observation in children have been successful in inducing desensitization; however, only a fraction of these children have long-lived tolerance. Patients undergoing PNOIT often have a decrease in their peanut-specific IgE and a gradual increase in their peanut-specific IgG and IgG4 levels, but the mechanistic contribution of these changes in peanut-specific immunoglobulins to long-term tolerance is still unknown. This project addresses how PNOIT affects the B cell repertoire and how those changes correlate to the heterogeneous clinical outcomes that are expected. We hypothesize that long-lasting clinical tolerance following PNOIT directly correlates with, and is partially dueto the induction of high affinity and oligoclonal allergen-specific functional antibodies. Using a fluorescent tetramer-based approach for the identification of allergen-specific B cells, we hope to identify clinical prognostic markers, and improve our understanding of the mechanism of immunotherapy, specifically the pathophysiological role of antibodies and their potential as both biomarkers of tolerance and therapeutic agents. To do so, we propose mapping the allergen-specific B cell repertoire using proteomics and next- generation sequencing in PNOIT patients. We also propose functional studies of recombinant antibodies from the allergen-specific B cells to explore the underlying mechanism of tolerance in PNOIT. By studying both peanut allergic patients who develop variable tolerance during PNOIT as well as peanut allergic patients who naturally outgrew their allergies, we hope to elucidate the contribution of the B cell repertoire t the induction of long-lived tolerance in peanut allergy. These efforts may help identify relevant clinical biomarkers and potential therapeutic avenues for the improvement of PNOIT for the treatment of peanut allergy.