Regulation of the Intestinal Stem Cells During Regeneration

再生过程中肠干细胞的调节

• 批准号: 10197117
• 负责人: David T Breault
• 金额: $ 47.45万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10197117
• 关键词: AXIN2 gene; Address; Adult; Biological Models; Biopsy; Birth; Cell Cycle; Cell Maintenance; Cell Survival; Cell physiology; Cells; Chemotherapy and/or radiation; Data; Development; EGR2 gene; Exposure to; Fasting; Fractionation; Gene Expression Profile; Generations; Genes; Genetic Transcription; Germ-Free; Homeostasis; Human; In Vitro; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Injury; Intestines; LGR5 gene; Lead; Life; Maintenance; Mediating; Microbe; Modeling; Molecular; Mus; Natural regeneration; OLFM4 gene; Organism; Pathologic; Pathway interactions; Patients; Perinatal; Phenotype; Physiological; Population; Positioning Attribute; Process; Quantitative Reverse Transcriptase PCR; RNA analysis; Regenerative capacity; Regenerative response; Regulation; Regulatory Pathway; Resistance; Role; Short Bowel Syndrome; Stimulus; Stress; Testing; Tissues; Toxic effect; Transplantation; Uterus; WNT Signaling Pathway; base; crypt cell; cytokine; differential expression; experimental study; fetal; genetic signature; in vivo; inhibitor/antagonist; intestinal homeostasis; irradiation; knock-down; microbial; microbiome; mouse model; regenerative therapy; response; response to injury; severe injury; single-cell RNA sequencing; stem cell biomarkers; stem cell population; stem cell survival; stem cells; stressor; transcription factor; transcriptome; transcriptome sequencing; validation studies; virtual

Intestinal stem cells (ISCs) mediate the regenerative response that follows injury to the gut, though the mechanisms that regulate these essential cells remain poorly understood. In the adult, Wnt-responsive Wnt(+) Lgr5+ ISCs are required for intestinal maintenance, but these cells are exquisitely sensitive to injury (e.g., irradiation, inflammation, fasting). In contrast, a reserve population of dormant (d)-ISCs, such as those marked by mTert expression, are highly resistant to injury and become activated to restore Lgr5+ ISCs and tissue homeostasis. Our recent data indicate that d-ISCs (unlike Lgr5+ cells) are maintained in a Wnt-unresponsive Wnt(-) state. Similarly, fetal ISCs are Wnt(-) before birth and mature into Wnt(+) ISCs during the perinatal transition from intra- to extra-uterine life in response to unknown factors. Together, these observations suggest that the transition from a Wnt(-) to a Wnt(+) state is a crucial process for the generation of Lgr5+ ISCs during regeneration and development. Our recent analyses, using RNA-seq to compare Wnt(-) and Wnt(+) ISC populations, revealed multiple differentially expressed genes, underscoring that distinct regulatory pathways control these two ISC populations. Precisely how the Wnt(-) state is maintained in d-ISCs and how it impacts their regenerative response is largely unknown. To address this, we propose the following: Aim 1. Define the role of candidate regulatory factors and the identity of long-lived d-ISCs; Aim 2. Determine how the microbiome and/or its metabolites regulate ISC survival; and Aim 3. Investigate the role of human (h)Tert+ cells in intestinal homeostasis. These studies seek to understand the regulatory mechanisms that govern Wnt(-) ISC maintenance and survival and regulate their transition into Wnt(+) ISCs. The successful completion of these studies may lead to targeted new regenerative therapies for patients suffering from inflammatory bowel disease, short gut syndrome, environmental enteropathy and intestinal toxicity resulting from exposure to radiation and chemotherapy.

肠道干细胞（ISC）介导肠道损伤后的再生反应， 尽管调节这些重要细胞的机制仍然知之甚少。在 成人、Wnt 反应性 Wnt(+) Lgr5+ ISC 是肠道维持所必需的，但这些细胞 对损伤（例如辐射、炎症、禁食）极其敏感。相比之下，储备金 休眠 (d)-ISC 群体，例如那些以 mTert 表达为标志的群体，具有高度耐药性 损伤并被激活以恢复 Lgr5+ ISC 和组织稳态。我们最近的数据 表明 d-ISC（与 Lgr5+ 细胞不同）维持在 Wnt 无反应 Wnt(-) 状态。 同样，胎儿 ISC 在出生前为 Wnt(-)，并在围产期成熟为 Wnt(+) ISC 响应未知因素从宫内生活过渡到宫外生活。在一起，这些 观察表明，从 Wnt(-) 状态到 Wnt(+) 状态的转变是 再生和发育过程中 Lgr5+ ISC 的产生。我们最近的分析，使用 RNA-seq 比较 Wnt(-) 和 Wnt(+) ISC 群体，揭示了多个差异 表达基因，强调不同的调控途径控制这两个 ISC 人口。准确地说，d-ISC 中如何维持 Wnt(-) 状态以及它如何影响它们 再生反应在很大程度上是未知的。为了解决这个问题，我们提出以下建议： 目标 1. 定义候选调控因子的作用和长寿命 d-ISC 的身份； 目标 2. 确定微生物组和/或其代谢物如何调节 ISC 存活；和 目标 3. 研究人 (h)Tert+ 细胞在肠道稳态中的作用。 这些研究旨在了解控制 Wnt(-) ISC 的调控机制 维持和存活并调节它们向 Wnt(+) ISC 的转变。成功者 这些研究的完成可能会为患者带来有针对性的新再生疗法 患有炎症性肠病、短肠综合症、环境性肠病和 暴露于放射线和化学疗法导致的肠道毒性。