Propagation of graft vs. host disease through CD4+ T-cell cognate recognition of gastrointestinal microbiota

项目摘要/摘要 这项建议提出了一个为期五年的研究职业发展计划，重点是T细胞的研究 造血干细胞移植后的重建及其移植物抗宿主病 可以通过对微生物区系的克隆型反应来塑造。该候选人目前是该大学的医学讲师。 华盛顿大学和弗雷德·哈钦森癌症研究中心副研究员。这 该计划建立在候选人以前的研究和临床经验的基础上，提供以下方面的高级培训 他的导师团队杰弗里·希尔博士(HSCT中的GVHD)和菲利普博士代表了两个专业领域 布拉德利(T细胞反应的计算模型)。建议的实验和教学工作将 为应聘者提供一套独特的跨学科技能，使其能够过渡到 作为一名独立的内科科学家在造血干细胞移植中T细胞介导的免疫。 T细胞在移植物抗宿主病的发病机制中起着基础性作用，移植物抗宿主病仍然是治疗成功的主要障碍。 造血干细胞移植在多种良性和恶性血液病中的应用。GVHD的参与 胃肠道(GI)仍然是发病率和死亡率的主要原因。美国退伍军人的组成 微生物组与移植物抗宿主病的发病和严重程度有关，尽管目前对其特异性的了解 GVHD的致病微生物种类仍与有限的机制密切相关 洞察力。虽然微生物组是T细胞同源抗原的主要来源，但人们对其来源知之甚少。 在这种情况下，抗微生物的TCR可能会导致病理改变。解析的部分困难在于 来自克隆水平的免疫监测的同种异体反应反应包括αβ的巨大组合多样性 TCRs，低拷贝数TCRs在任何给定的捐赠者池中的高流行率，以及抽样限制。这个 这项提议的基础是使用一种新的计算算法进行初步研究，以确定 扩大的供体TCR不受供体和宿主遗传学的限制，但似乎受到影响 由共生微生物。 这些抗微生物的TCR究竟如何在移植后的环境中发挥作用及其生理作用 与全球艾滋病毒/艾滋病的相关性是这项提案开始解决的问题。更具体地说，这样做的目的是 建议是1)在scRNA序列平台中验证通过计算识别的抗微生物CD4+TCR，以及 定义与隔室定位有关的细胞表型，2)通过计算识别的重建 并通过基因组筛选确定抗原特异性；3)剖析其功能作用 已鉴定的抗微生物CD4+TCRs在急性移植物抗宿主病传播中的作用。科学的 这项建议的目的是研究异基因干细胞后克隆型T细胞扩增的驱动因素 移植和评估GVHD的发病机制如何与微生物监测相结合。

PROJECT SUMMARY/ABSTRACT This proposal presents a five-year research career development program focused on the study of T-cell reconstitution following hematopoietic stem cell transplantation (HSCT) and how graft-vs-host disease (GVHD) can be shaped by clonotypic response to microbiota. The candidate is currently an Instructor of Medicine at the University of Washington and Research Associate at the Fred Hutchinson Cancer Research Center. This proposal builds on the candidate’s previous research and clinical experience by providing advanced training in two domains of expertise represented by his mentor team of Dr. Geoffrey Hill (GVHD in HSCT) and Dr. Philip Bradley (computational modeling of the T-cell response). The proposed experiments and didactic work will provide the candidate with a unique set of cross-disciplinary skills that will enable his transition to independence as a physician scientist in T cell mediated immunity in HSCT. T-cells play a fundamental role in the pathogenesis of GVHD which remains a major barrier for the successful application of HSCT for a wide range of benign and hematologic malignancies. GVHD involvement of the gastrointestinal (GI) tract remains a major cause of morbidity and mortality. The composition of the GI microbiome is associated with onset and severity of GVHD, though current understanding of how specific microbial species contribute to GVHD pathogenesis remains largely correlative with limited mechanistic insights. While the microbiome acts as a major source of cognate antigen for T cells, little is known about how anti-microbial TCRs may contribute to pathology in this setting. Part of the difficulty in parsing out the alloreactive response from immune surveillance on a clonal level includes the vast combinatorial diversity of αβ TCRs, the high prevalence of low copy number TCRs in any given donor pool, and sampling limitations. The foundation of this proposal is based on preliminary studies using a novel computational algorithm to identify expanded donor TCRs that are not constrained by donor and host genetics, but rather appear to be influenced by commensal microbes. How exactly these anti-microbial TCRs might function in the post-transplant context and its physiological relevance to GVHD are questions that this proposal begins to address. More specifically, the aims of this proposal are to 1) Validate computationally identified anti-microbial CD4+ TCRs in an scRNA seq platform and define cellular phenotypes in relation to compartment localization, 2) Reconstruct computationally identified CD4+ TCRs and determine antigenic specificity through genomic screening, and 3) Dissect the functional role of identified anti-microbial CD4+ TCRs on the propagation of acute graft-vs-host disease. The scientific objective of this proposal is to examine the drivers of clonotypic T-cell expansion following allogeneic stem cell transplant and assess how the pathogenesis of GVHD is coupled to microbial surveillance.