Robustness of the Intestinal Stem Cell Niche

肠道干细胞生态位的稳健性

• 批准号: 9044805
• 负责人: Xiling Shen
• 金额: $ 30.61万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-06 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9044805
• 关键词: 3-Dimensional; 3D Print; Abdomen; Ablation; Address; Algorithms; Alleles; Animals; Area; Behavior; Biological Assay; Biological Models; Cell Lineage; Cells; Chronic; Colon Carcinoma; Columnar Cell; Development; Disease; Engraftment; Environment; Epithelium; Event; Feedback; Genetic Engineering; Health; Homeostasis; Image; Imaging Techniques; Implant; Individual; Injection of therapeutic agent; Intestines; Label; Laser Microscopy; Lasers; Left; Life; Ligands; Link; Microscopy; Modeling; Monitor; Movement; Mus; Mutation; Natural regeneration; Nature; Organoids; Paneth Cells; Pathway interactions; Physiologic pulse; Printing; Recovery; Reporter; Resolution; Role; Signal Pathway; Signal Transduction; Small Intestines; Specific qualifier value; Stem Cell Research; Stem cell transplant; Stem cells; System; Systems Analysis; Systems Biology; Techniques; Technology; Testing; Tissues; Transgenic Mice; Validation; adult stem cell; animal imaging; base; blastocyst; cancer stem cell; cell type; computer framework; coping; daughter cell; dynamic system; imaging system; improved; in vivo; innovation; insight; interdisciplinary approach; intestinal crypt; intestinal epithelium; multi-scale modeling; notch protein; novel; regenerative; resilience; spatiotemporal; stem cell biology; stem cell niche; stem cell population; theories; time use; tool; transcriptome

 DESCRIPTION (provided by applicant): The intestinal epithelium is one of the fastest regenerative tissues in the body. Regeneration is sustained by a group of stem cells, termed crypt base columnar cells (CBCs), at the bottom of the intestinal crypt. In the past 5 years, studies of CBCs have helped transform the dogma of stem cell biology. Rather than being largely quiescent, undergoing asymmetric division, and following the unidirectional differentiation hierarchy, CBCs are highly proliferative, capable of symmetric division, and replaceable by more differentiated cell types. Since then, similar stem cell populations and regulatory principles have been identified in many other tissues. However, all these discoveries converge on a central question: how does the stem cell niche control plasticity in order to keep a constant number of CBCs? Since proliferative CBCs have been linked to colon cancer, and stem cell transplants are being used clinically for treating a variety of diseases, it is importantto understand the underlying control. Cellular dynamics Innovative multiphoton imaging and laser ablation technologies will be used to investigate how cells divide, move and recover loss inside the stem cell niche, focusing on four fundamental questions: (1) are CBCs capable of both symmetric and asymmetric division, (2) do individual CBCs in the same niche have equal proliferative potential, (3) how does the niche recover from cell loss, and (4) how do cells outside the niche dedifferentiate and reenter the niche? Signaling dynamics Using the 3D intestinal organoid assay, a systematic study will be carried out to search for feedback and crosstalk mechanisms among major signaling pathways. Dynamical systems analysis will be performed to understand their impact on the niche control circuitry. Integration and Validation To integrate experimental findings and computational insights, a stochastic, multiscale model will be built that captures cellular division, movement and signaling events in the stem cell niche. This model will be used to test hypotheses on the niche control circuitry. A novel engraftment assay through injection of genetically engineered stem cells into blastocysts has been developed for in vivo validation. Innovation Novel in vivo GI imaging techniques have been developed by using openable abdominal window, 3-D printed intestinal support, labeled vasculature roadmap, and tracking algorithms. Through the window, a special laser can ablate a single cell inside the niche without damaging the surrounding tissue. A computational framework will integrate dynamical systems analysis and multiscale modeling to study the regulatory circuitry that controls cellular and signaling dynamics inside the niche. Predictions will be validated in novel chimeric mice with intestinal crypts derived from blastocyst-injected cells. Preliminary findings The stem cell niche undergoes extensive reorganization after loss of one CBC, attesting to its dynamic nature. Various feedback and crosstalk mechanisms have been identified to improve robustness.

 描述（由适用提供）：肠上皮是体内最快的再生组织之一。再生由肠道底部的一组干细胞（称为隐窝底柱细胞（CBC））维持。在过去的5年中，对CBC的研究有助于改变干细胞生物学的教条。 CBC不是在很大程度上是静止的，不对称分裂，并且在单向分化层次结构之后，不如说是高度增殖，能够对称分裂，并且可以被更具差异化的细胞类型替代。从那时起，在其他许多时候已经确定了类似的干细胞群体和调节原理。但是，所有这些发现都融合了一个中心问题：干细胞生态位如何控制可塑性以保持恒定数量的CBC？由于增殖的CBC与结肠癌有关，并且在临床上使用干细胞移植来治疗多种疾病，因此了解潜在的控制很重要。 Cellular dynamics Innovative multiphoton imaging and laser ablation technologies will be used to investigate how cells divide, move and recover loss inside the stem cell niche, focusing on four fundamental questions: (1) are CBCs capable of both symmetric and asymmetric division, (2) do individual CBCs in the same niche have equal proliferation potential, (3) How does the niche recover from cell loss, and (4) how do cells在利基市场之外进行推迟并重新进入利基市场？使用3D肠道器官测定的信号传导动力学，将进行系统研究，以搜索主要信号通路之间的反馈和串扰机制。将进行动态系统分析以了解其对利基控制电路的影响。集成和验证以整合实验发现和计算见解，将建立一个随机的多尺度模型，该模型捕获干细胞小众中的细胞分裂，运动和信号传导事件。该模型将用于测试利基控制电路上的假设。通过将一般工程的干细胞注入胚泡的新型植入测定已被开发用于体内验证。创新小说在体内GI成像技术是通过使用可开放的腹部窗户，3-D打印的肠道支撑，标记为脉管图路线图和跟踪算法来开发的。通过窗户，特殊的激光可以在小众内部消除一个单个单元，而不会损害周围的组织。一个计算框架将整合动态系统分析和多尺度建模，以研究控制利基内部细胞和信号动力学的调节电路。预测将在新型嵌合小鼠中得到验证，该小鼠具有源自注射胚泡细胞的肠道加密。初步发现干细胞生态位在失去一个CBC后经历了广泛的重组，证明其动态性质。已经确定了各种反馈和串扰机制以提高鲁棒性。