A mosaic Down syndrome model system comparing isogenic trisomic/disomic cells to unmask trisomy-21 related genomic, epigenomic, and senescence changes acquired across the lifespan

镶嵌唐氏综合症模型系统比较同基因三体/二体细胞，以揭示在整个生命周期中获得的与 21 三体相关的基因组、表观基因组和衰老变化

• 批准号: 10656746
• 负责人: COLLEEN K JACKSON-COOK
• 金额: $ 221.74万
• 依托单位: VIRGINIA COMMONWEALTH UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10656746
• 关键词: 21 year old; Acceleration; Adolescence; Adult; Age; Aging; Algorithms; Aneuploidy; Area; Behavioral; Bioinformatics; Biological; Biological Assay; Biological Factors; Biological Markers; Biological Models; Blood; Bystander Effect; Cataract; Cells; Childhood; Chromosome 21; Chromosomes; Clinical Research; Cytogenetics; Cytoplasm; DNA; DNA Methylation; Data; Dementia; Development; Disease; Down Syndrome; Early Onset Alzheimer Disease; Epigenetic Process; Event; Fluorescent in Situ Hybridization; Frequencies; Functional disorder; Gene Expression; General Population; Genomics; Goals; Health; Homeostasis; Immunofluorescence Immunologic; Immunologic Surveillance; Individual; Inflammation; Interferons; Knowledge; Lead; Length; Longevity; Longitudinal Studies; Lymphocyte; Measures; Mediating; Mediator; Methods; Methylation; Micronucleus Tests; Modeling; Mosaicism; Natural Immunity; Outcome; Pathway interactions; Pattern; Personal Satisfaction; Persons; Phenotype; Physicians; Process; Quality of life; Research; Research Design; Risk; Role; Sentinel; Somatic Cell; Specimen; Spectral Karyotyping; Stimulator of Interferon Genes; Symptoms; System; Technology; Telomere Shortening; Testing; Therapeutic; Time; Tissues; age related; beta-Galactosidase; cell type; cytokine; early detection biomarkers; emerging adult; epigenomics; expectation; follow-up; genetic makeup; genome-wide; genome-wide analysis; hearing impairment; improved; infancy; methylation pattern; micronucleus; mortality; mosaic; new therapeutic target; novel; phenotypic data; proband; reduce symptoms; response; screening; senescence; telomere; timeline; tool; trait; transcriptome; transcriptomics

PROJECT SUMMARY Down syndrome (Ds) has been associated with multiple, co-occurring health and behavioral conditions, as well as precocious (or accelerated) aging. The results of recent clinical studies are providing a clearer picture of health outcomes in childhood, adolescence, and early adulthood in people with Ds; yet very little is known about the cascade of trisomy 21-related biological changes that arise to culminate in the development of co-occurring conditions. The recent discovery of cytosolic DNA as an “integrator” of changes acquired in somatic cells provides a new research direction for identifying age- and trisomy 21-related biological alterations. Cells can acquire cytosolic DNA via micronuclei (MN) formation and extrachromosomal telomere circles (t-circles). A subset of this cytoplasmic self-DNA is recognized by innate immune surveillance pathways, which, in turn, lead to increased levels of senescence. We hypothesize that trisomy 21 increases MN levels and telomere attrition, leading to a perpetuating cycle of senescence and methylation alterations that accumulate/increase in frequency with age. One powerful approach for discovering trisomy 21-specific alterations is to evaluate biological attributes in cells from people with mosaicism for trisomy 21 (mDs). One can unmask and quantify trisomy 21-induced changes by “subtracting” values observed in isogenic disomic cells from those present in trisomic cells (thereby removing the confounding effects due to total background genetic make-up, as well as environmental influences). Thus, to identify the impact of a trisomy 21 imbalance on cytosolic DNA pathways, we will longitudinally compare biological measures in isogenic trisomic versus disomic cells from 65 people with mDs over 3 time points, (including baseline data, and spanning as much as 30 years of follow-up). To test our study hypothesis, we will quantify: (1) cytosolic self-DNA via a MN assay; (2) subtelomere/telomere alterations or dysfunction; (3) senescence patterns and cytokine levels; and (4) DNA methylation patterns. Each of these biological factors will be analyzed with “state of the art” tools we developed/optimized, which include: chromosome-specific assays for MN [SKY/FISH MN assay]); novel telomere/subtelomere length assays [Q-FISH & nanomapping]; telomere dysfunction assays; senescence, transcriptome, and cytokine marker assays; genome-wide studies for DNA methylation; and bioinformatic modeling. We will also collect/evaluate deep phenotype data. By interrogating relationships among and between biological measures with phenotypic traits, we will discover their role in mediating health outcomes. In summary, this longitudinal study of isogenic trisomic/disomic cells will enable us to “unmask” trisomy 21-associated changes in biological cascades and will provide the first assessment of the role of cytosolic DNA in health conditions associated with Ds/mDs. By identifying driver/mediator relationships between biomarkers, we will create new algorithms that will help physicians recognize health conditions at an earlier age in people with Ds/mDs. Importantly, we will identify new therapeutic targets that could transform our approach for developing treatments to alleviate symptoms of health conditions acquired by people with mDs/Ds.

项目摘要 唐氏综合征（Ds）与多种同时发生的健康和行为状况有关， 早熟（或加速老化）。最近的临床研究结果提供了一个更清晰的画面， 儿童期、青少年期和成年早期的健康结果;然而， 21三体相关生物学变化的级联反应，最终导致共同发生的 条件最近发现胞质DNA作为体细胞中获得的变化的“整合者” 为识别年龄和21三体相关的生物学改变提供了新的研究方向。细胞可以 通过微核（MN）形成和染色体外端粒环（t环）获得胞质DNA。一 这种细胞质自身DNA的子集被先天免疫监视途径识别，这反过来又导致 衰老程度的增加。我们假设21三体增加了MN水平和端粒磨损， 导致衰老和甲基化改变的永久循环， 随年龄发现21三体特异性改变的一个强有力的方法是评估生物学属性 在21三体嵌合体（mDs）患者的细胞中。人们可以揭示和量化21三体诱导的 通过从存在于三体细胞中的那些值中“减去”在等基因二体细胞中观察到的值（从而 除去由于总背景遗传组成以及环境影响而引起的混杂效应）。 因此，为了确定21三体不平衡对胞质DNA途径的影响，我们将纵向比较 来自65名在3个时间点内具有mDs的人的等基因三体细胞与二体细胞的生物学测量， （包括基线数据和长达30年的随访）。为了验证我们的研究假设，我们将 定量：（1）通过MN测定的细胞溶质自身DNA;（2）亚端粒/端粒改变或功能障碍;（3） 衰老模式和细胞因子水平;和（4）DNA甲基化模式。这些生物因素中的每一个都会 使用我们开发/优化的“最先进”工具进行分析，其中包括： MN [SKY/FISH MN测定]）;新型端粒/亚端粒长度测定[Q-FISH和纳米作图];端粒 功能障碍测定;衰老、转录组和细胞因子标记物测定; DNA全基因组研究 甲基化;和生物信息学建模。我们还将收集/评估深层表型数据。通过询问 之间的关系和生物措施与表型性状，我们将发现他们的作用， 调节健康结果。总之，这种对同基因三体/二体细胞的纵向研究将使我们能够 “揭露”21三体相关的生物级联变化，并将提供第一次评估， 细胞质DNA在与Ds/mDs相关的健康状况中的作用。通过确定驱动者/中介者关系 在生物标志物之间，我们将创建新的算法，帮助医生以最快的速度识别健康状况。 D/MD患者的年龄较早。重要的是，我们将确定新的治疗靶点， 开发治疗方法以缓解mDs/Ds患者获得的健康状况症状。