Studying a bone marrow failure disease using patient-specific iPS cells

使用患者特异性 iPS 细胞研究骨髓衰竭疾病

• 批准号: 8353117
• 负责人: Luis Francisco Zirnberger Batista
• 金额: $ 12.4万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8353117
• 关键词: Adult; Affect; Age; Aging; Aplastic Anemia; Binding; Biochemical; Blood Cells; Bone Marrow; Cell Line; Cell physiology; Cells; ChIP-seq; Chromatin; Chromosomes; Clinical; Clinical Protocols; Complement; Complex; Custom; DNA-Directed DNA Polymerase; Defect; Development; Disease; Drug Delivery Systems; Dyskeratosis Congenita; Event; Functional disorder; Future; Gene Expression; Genes; Genetic; Goals; Hematopoietic; Hematopoietic Stem Cell Transplantation; Hematopoietic stem cells; Homeostasis; Human; Inherited; Knowledge; Length; Life; Life Expectancy; Link; Mammalian Cell; Methods; Modeling; Molecular; Molecular Profiling; Mus; Mutation; Nail plate; Organ; Outcome; Pancytopenia; Pathway interactions; Patients; Pharmaceutical Preparations; Phase; Phenotype; Physiological; Population; Preclinical Drug Evaluation; Process; Pulmonary Fibrosis; RNA Sequences; Regenerative Medicine; Regulation; Rest; Ribonucleoproteins; Screening procedure; Severities; Signal Transduction; Skin; Somatic Cell; Stem cells; Syndrome; System; Technology; Telomerase; Telomere Maintenance; Telomere Shortening; Tissues; adult stem cell; alternative treatment; cell type; cellular development; coping; design; disease phenotype; drug discovery; high throughput analysis; human tissue; induced pluripotent stem cell; mutant; novel; novel strategies; patient population; premature; research study; response; self-renewal; small molecule; stem; stem cell division; stem cell technology; telomere; therapy development; tool

DESCRIPTION (provided by applicant): The goal of this project is to use patient-specific induced pluripotent stem cells (iPSCs) as a platform for the development of novel therapies for patients suffering with dyskeratosis congenita (DC), a bone-marrow failure syndrome that presents with poor life expectancy and multi-systemic tissue defects that include aplastic anemia and pulmonary fibrosis. A combination of technologies will be used to achieve this goal, including genetic correction, high-throughput sequencing, small-molecule drug screening and targeted differentiation of DC iPS cells to hematopoietic fates. All patients with DC have very short telomeres for their age, typically below the first percentile length when compared to the rest of the population. All mutations discovered in DC so far were in genes related to telomere homeostasis, either in telomerase, or directly binding to telomeres. Telomerase is the multi-enzymatic complex responsible for telomere synthesis in mammalian cells. In the absence of telomerase, telomeres will progressively shorten, which has been linked to impaired stem cell function in mice and humans. Thus, the tissue defects observed in DC likely result from the loss of self-renewal in adult stem cells compartments of these patients, caused by accelerated telomere shortening in settings of mutant telomerase. The central hypothesis of this project is that disease-specific iPS cells offer a novel and suitable system to study the consequences of mutant telomerase and the loss of self-renewal in DC pluripotent cells and can be used to search for strategies to correct this phenotype. I have previously shown that iPS cells derived from patients showing variable severity of DC faithfully recapitulate the telomere shortening and loss of self-renewal phenotypes observed in human patients. Here, I propose to use these patient-specific iPS cells to understand in detail the loss of self-renewal phenotype arising from dysfunctional telomeres and to use these cells as a platform for drug discovery and targeted differentiation, which could enable novel protocols for clinical therapy in the future. The Specifi Aims are (I) to reverse the self-renewal defect in DC patient-specific iPS cells by genetic complementation and high- throughput gene expression analysis of DC iPS cells with critically short telomeres and (II) to use DC iPS cells as a platform for developing new therapies against DC, by searching for telomerase stabilizing drugs and by specifically differentiating these cells into hematopoietic fates. This project will significantly increase the current knowledge on bone-marrow failure syndromes, by first understanding the deleterious effects of dysfunctional telomeres in human pluripotent cells, and then by devising novel strategies to treat patients afflicted with dyskeratosis congenita, a disease that currently has no cure.

描述（由申请人提供）：该项目的目标是使用患者特异性诱导多能干细胞（iPSC）作为平台，为患有先天性角化不良（DC）的患者开发新型疗法，先天性角化不良（DC）是一种骨髓衰竭综合征，表现为预期寿命短和多系统组织缺陷，包括再生障碍性贫血和肺纤维化。将使用多种技术的组合来实现这一目标，包括遗传校正、高通量测序、小分子药物筛选和DC iPS细胞向造血命运的靶向分化。 所有患有DC的患者具有相对于其年龄的非常短的端粒，当与其余人群相比时，通常低于第一百分位数长度。到目前为止，在DC中发现的所有突变都与端粒稳态相关的基因中，或者在端粒酶中，或者直接与端粒结合。端粒酶是哺乳动物细胞中负责端粒合成的多酶复合物。在没有端粒酶的情况下，端粒会逐渐缩短，这与小鼠和人类干细胞功能受损有关。因此，在DC中观察到的组织缺陷可能是由于这些患者的成体干细胞区室中的自我更新丧失所致，这是由突变型端粒酶环境中加速的端粒缩短引起的。该项目的中心假设是，疾病特异性iPS细胞提供了一种新的和合适的系统来研究突变端粒酶的后果和DC多能细胞自我更新的丧失，并可用于寻找纠正这种表型的策略。 我以前已经表明，iPS细胞来源于患者表现出不同的严重程度的DC忠实地重演端粒缩短和自我更新表型的损失在人类患者中观察到。在这里，我建议使用这些患者特异性iPS细胞来详细了解端粒功能障碍引起的自我更新表型的丧失，并将这些细胞作为药物发现和靶向分化的平台，这可能会使未来的临床治疗方案成为可能。具体目的是（I）通过具有极短端粒的DC iPS细胞的遗传互补和高通量基因表达分析来逆转DC患者特异性iPS细胞中的自我更新缺陷，和（II）通过寻找端粒酶稳定药物和通过特异性地将这些细胞分化为造血命运，使用DC iPS细胞作为开发针对DC的新疗法的平台。 该项目将通过首先了解人类多能细胞中功能失调的端粒的有害影响，然后通过设计新的策略来治疗患有先天性角化不良的患者，这是一种目前无法治愈的疾病，从而显着增加目前对骨髓衰竭综合征的认识。