The Impact of Donor Hematopoietic DNMT3A Mutations in Stem Cell Transplant Recipients

项目概要/摘要 造血细胞移植（HCT）是恶性血液病患者的重要治疗手段 （HM）。它的成功取决于供体造血细胞建立长期造血的能力， 免疫介导的残留恶性细胞消除。克隆性造血（CH）是一种与年龄相关的 一种可检测到的体细胞突变改变了生物学功能和炎症输出的疾病， 在造血细胞和非移植人群中，与不良结局一致相关。通过 通过研究1727对HCT供受者，我发现CH在供者中很常见， DNMT 3A基因是最常见的变异。我的初步数据显示供体DNMT 3A-CH是 与改善的全球接受者结局相关，由HM复发风险降低介导，但也 增加了一部分接受者移植失败的风险。根据这些数据和已知的函数， DNMT 3A在造血细胞中的作用，我假设供体DNMT 3A-CH I在HCT受者中观察到的作用 是由于DNMT 3A突变的长期造血干细胞的植入和随后的功能改变 在成熟的DNMT 3A突变型白细胞亚群中，特别是T细胞中。为了验证这个假设，我提出以下建议 两个目的：（1）确定HCT后DNMT 3A-CH对正常和受损造血的作用。我会 使用基因组、免疫表型和单细胞技术来定义特征，包括细胞 区室，移植到受体中的供体DNMT 3A突变。然后我将着重阐述 （2）明确DNMT 3A-CH在供体肾移植中的作用。 移植后植入的T细胞。我将使用基因组、免疫表型和单细胞技术， 确定供体DNMT 3A突变对受体中T细胞组成和功能的影响， 移植，特别关注DNMT 3A突变如何调节T细胞耗竭的发展。 然后，我将具体评估T细胞中供体DNMT 3A突变如何影响免疫逃避途径 急性髓细胞白血病复发病例中使用。从这些研究中获得的信息将提供 对移植后造血和免疫监视生物学的新见解， 供体选择和策略的影响，以增加移植物抗白血病的效果。灯会随着 根据提议的实验，我概述了一个五年职业发展计划，目标是成为一名 翻译移植研究的独立研究员。我召集了一个全球性的咨询委员会 造血、移植免疫学和生物统计学方面的公认专家，提供实验输入 在这些领域的具体培训。丹娜-法伯癌症研究所，拥有一项杰出的研究 一个社区，并有长期的记录，为独立的医生科学家成功的导师，是一个理想的 这是我完成这些实验和实现我的短期和长期职业目标的环境。

PROJECT SUMMARY/ABSTRACT Hematopoietic cell transplant (HCT) is an important treatment modality for patients with hematologic malignancy (HM). Its success depends on the ability of donor hematopoietic cells to establish long-term hematopoiesis and immunologically mediated elimination of residual malignant cells. Clonal hematopoiesis (CH) is an age-related condition in which detectable somatic mutations alter the biologic function and inflammatory output of hematopoietic cells, and in non-transplant populations is uniformly associated with adverse outcomes. By studying 1727 HCT donor-recipient pairs, I found that CH in donors is common and that inactivating mutations in the gene DNMT3A are the most frequent alterations. My preliminary data shows that donor DNMT3A-CH is associated with improved global recipient outcomes, mediated by a reduced risk of HM relapse, but also increases the risk of graft failure in a subset of recipients. Based on these data and the known function of DNMT3A in hematopoietic cells, I hypothesize that the effects of donor DNMT3A-CH I observe in HCT recipients are due to engraftment of DNMT3A-mutated long-term hematopoietic stem cells and subsequent altered function in mature DNMT3A-mutant leukocyte subsets, particularly T cells. To test this hypothesis, I propose the following two aims: (1) Determine the effect of DNMT3A-CH on normal and impaired hematopoiesis following HCT. I will use genomic, immunophenotypic, and single-cell technologies to define the characteristics, including cellular compartment, of donor DNMT3A mutations that engraft in recipients. I will then focus on elucidating the biology of graft failure developing in recipients of donor DNMT3A-CH. (2) Define the effect of DNMT3A-CH in donor- engrafted T-cells after transplantation. I will use genomic, immunophenotypic, and single-cell techniques to determine the effect of donor DNMT3A mutations on T-cell composition and function in recipients after transplantation, focusing specifically on how DNMT3A mutations modulate the development of T-cell exhaustion. I will then specifically assess how donor DNMT3A mutations in T cells affect the pathways of immune evasion utilized by relapsing cases of acute myeloid leukemia. The information gained from these studies will provide new insights into the biology of post-transplant hematopoiesis and immune surveillance that could have profound implications for donor selection and strategies to augment the graft-versus-leukemia effect. In concert with the proposed experiments, I have outlined a five-year career development plan aimed at the goal of becoming an independent investigator in translational transplant research. I have assembled an advisory committee of globally recognized experts in hematopoiesis, transplant immunology, and biostatistics, to provide experimental input and specific training in these fields. Dana-Farber Cancer Institute, which harbors an outstanding research community and has a long track record for successful mentorship of independent physician scientists, is an ideal environment for completion of these experiments and realization of my short and long-term career goals.