Mechanistic modeling of epigenetic modifier mutations in human pluripotent stem cell-derived immune cells

人类多能干细胞衍生的免疫细胞表观遗传修饰突变的机制模型

基本信息

批准号：
10733331
负责人：
Minji Byun
金额：
$ 19.63万
依托单位：
UNIVERSITY OF CALIFORNIA-IRVINE
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10733331
关键词：
ATAC-seq Ablation Acceleration Address Affect Age Aging Atherosclerosis Automobile Driving Base Pairing Binding Biochemical Biological Biology Blood Cells Cardiovascular Diseases Cell model Cells ChIP-seq Chromatin Clinical Clonal Expansion Clone Cells Complex DNA Methylation DNMT3a Data Defect Elderly Enhancers Enzymes Epigenetic Process Experimental Models Family Future Gene Combinations Gene Expression Gene Expression Profiling Genes Genetic Diseases Genetic Models Genetic Transcription Hematologic Neoplasms Hematology Hematopoiesis Heterozygote Human Immune Immune response Impairment Individual Inflammation Knowledge Macrophage Measurement Measures Modeling Molecular Morbidity - disease rate Mus Mutate Mutation Myelogenous Myeloid Cells Null Lymphocytes Orthologous Gene Outcome Pathogenicity Pathology Pathway interactions Phenotype Population Prevention Proteins Research Research Personnel Resolution Risk Side Somatic Mutation Testing Work atherosclerosis risk demethylation differential expression genetic manipulation human pluripotent stem cell in vitro Model in vivo knock-down loss of function loss of function mutation mortality public health priorities therapeutic target transcription factor transcriptome

项目摘要

PROJECT SUMMARY Clonal hematopoiesis of indeterminate potential (CHIP) refers to the presence of expanded blood cell clones with one or more somatic mutations without other hematologic abnormalities. CHIP is common in the elderly, affecting more than 10% of individuals over 65 years. CHIP is associated with a 10-fold increase risk of hematologic malignancies and a doubled risk of atherosclerotic cardiovascular disease, contributing to an increase in all-cause mortality. The two most commonly mutated genes in CHIP are DNMT3A and TET2, both of which encode epigenetic modifiers. Recent studies have found evidence of increased inflammation and worsened atherosclerosis when the murine ortholog of TET2 was perturbed in myeloid cells in vivo. However, the specific epigenetic mechanism underlying this phenotype and whether DNMT3A and TET2 mutations target the same biological pathway are unclear. Furthermore, it remains unexplained why loss-of-function mutations in DNMT3A and TET2 have shared a clinical outcome despite the two genes encode enzymes with opposite biochemical functions (DNA methylation vs. de-methylation). To address this knowledge gap, we developed human pluripotent stem cell (hPSC)-derived macrophage models of DNMT3A- and TET2- haploinsufficiency. hPSC-derived macrophages are inexhaustible, scalable, and amenable to genetic manipulation, offering a powerful in vitro model well-suited for mechanistic studies. In this proposal, we propose the use of this model to (1) define unique and shared epigenetic features of DNMT3A and TET2 haploinsufficiency, and (2) identify transcription factors driving altered immune gene expression in DNMT3A- and TET2-haploinsufficient immune cells. This project is built on our previous work, and we anticipate that findings from this study will guide future studies on targeting an epigenetic vulnerability shared between DNMT3A- and TET2-mutated cells as well as mechanistic studies on other drivers of CHIP.

项目概要不确定潜力克隆造血 (CHIP) 是指存在扩增的血细胞克隆具有一种或多种体细胞突变，且无其他血液学异常。 CHIP 常见于老年人，影响超过 10% 的 65 岁以上的人。 CHIP 与增加 10 倍的风险相关血液系统恶性肿瘤和动脉粥样硬化性心血管疾病的风险加倍，导致全因死亡率增加。 CHIP 中两个最常见的突变基因是 DNMT3A 和 TET2，两者均其中编码表观遗传修饰因子。最近的研究发现炎症增加的证据当 TET2 的小鼠直系同源物在体内骨髓细胞中受到干扰时，动脉粥样硬化会恶化。然而，该表型背后的具体表观遗传机制以及 DNMT3A 和 TET2 是否突变靶向相同的生物学途径尚不清楚。此外，仍然无法解释为什么功能丧失 DNMT3A 和 TET2 的突变具有相同的临床结果，尽管这两个基因编码的酶具有相反的生化功能（DNA 甲基化与去甲基化）。为了解决这一知识差距，我们开发了 DNMT3A- 和 TET2- 的人多能干细胞 (hPSC) 衍生巨噬细胞模型单倍体不足。 hPSC 衍生的巨噬细胞取之不尽、用之不竭、可扩展且易于遗传操作，提供了非常适合机械研究的强大体外模型。在这个提案中，我们建议使用该模型来 (1) 定义 DNMT3A 和 TET2 独特且共享的表观遗传特征单倍体不足，以及（2）识别驱动 DNMT3A- 中免疫基因表达改变的转录因子和 TET2-单倍体不足的免疫细胞。该项目是建立在我们之前的工作基础上的，我们预计这项研究的结果将指导未来的研究，针对共同的表观遗传脆弱性 DNMT3A 和 TET2 突变细胞以及 CHIP 其他驱动因素的机制研究。