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）过敏和免疫学的医生，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，这导致了荧光过敏原特异性B细胞四聚体的开发，该四聚体可以成功地识别接受免疫治疗的花生过敏患者外周中的花生特异性B细胞。在该技术的基础上，这项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对花生过敏原Ara h 2的免疫球蛋白反应，从而更深入地了解食物过敏人类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地将Patil博士定位为人力资源第一个R 01应用程序和独立的医学科学家职业生涯。导师、培训活动和环境：Patil博士将在韦恩·什里夫勒博士的指导下在MGH的免疫学和炎症性疾病中心（CIID）以及在J·克里斯托弗·洛夫博士的共同指导下在马萨诸塞州理工学院（MIT）执行拟议的项目。CIID是一个多学科的基础科学中心，作为MGH免疫学研究的基础。此外，MGH的Robert Anthony博士和耶鲁大学医学院的Steven Kleinstein博士将担任Patil博士的咨询委员会成员，分别提供关于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库分析的专业知识。为了补充她提出的项目和她的导师的专业知识，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，测序，蛋白质组学和生物信息学的教学课程。合作机会，知识环境和资源提供给帕蒂尔博士是杰出的。研究：IgE介导的花生过敏构成了重大的公共卫生风险，因为花生暴露分钟可引起严重的过敏反应。花生口服免疫疗法（PNOIT）的临床试验，在儿童中仔细观察下逐渐增加花生暴露，已成功诱导脱敏;然而，只有一小部分儿童具有长期耐受性。接受PNOIT的患者通常花生特异性IgE降低，花生特异性IgG和IgG 4水平逐渐升高，但花生特异性免疫球蛋白的这些变化对长期耐受性的机制仍不清楚。 该项目解决了PNOIT如何影响B细胞库以及这些变化如何与预期的异质性临床结果相关。我们假设PNOIT后持久的临床耐受性与高亲和力和寡克隆变应原特异性功能抗体的诱导直接相关，部分是由于这种诱导。使用基于荧光四聚体的方法鉴定变应原特异性B细胞，我们希望鉴定临床预后标志物，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的生物标志物的潜力。 为此，我们建议在PNOIT患者中使用蛋白质组学和下一代测序来绘制过敏原特异性B细胞库。我们还提出了从过敏原特异性B细胞的重组抗体的功能研究，以探索潜在的机制，在PNOIT的耐受性。通过研究在PNOIT期间产生可变耐受性的花生过敏患者以及自然生长超过其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的长期耐受性的贡献。这些努力可能有助于确定相关的临床生物标志物和改善PNOIT治疗花生过敏的潜在治疗途径。

 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.