Cellular, Molecular, and Functional Characterization of Quiescent/Active Intestin

描述(申请人提供)：肠道具有持续周转的特点，为成体干细胞的研究提供了一个优雅的系统。成体干细胞是一种自我更新和再生的细胞，因此在再生医学中具有很大的前景。研究提供了有关肠道干细胞自我修复或愈合能力的重要见解。 以及持续的维持和分化为所有不同类型的肠道细胞。然而，需要大量的研究来更好地了解ISCs亚群的不同状态和功能，以及这些亚群是如何调节的。在其他组织中，如头发和血液，静止的干细胞亚群被认为是至关重要的，特别是对于干细胞库的长期维持和对应激或损伤的再生。然而，在肠道中，是否存在真正的静止的ISCs和/或它们驻留在哪里是一个有争议的问题。本研究认为，真正的静止的ISCs与活跃的ISCs共存。活跃的亚群负责肠上皮细胞系的生成和再生，而静止的亚群则作为储备池来补充丢失的活跃的ISCs和受损的组织。这项研究的目的是进一步研究4个静止的ISC细胞，并确定静止和活跃的ISC亚群的潜在分子调控。将使用的方法包括：表面标记、体外培养和体内谱系追踪分析，以鉴定和表征稳定和应激条件下静止的ISCs；RNA测序，以确定特定因子(Frizzled5和/或7)如何以及在哪里介导调控ISC维持、激活、自我更新和定位的信号(非规范和/或经典Wnt)；以及遗传小鼠模型，以研究蛋白质失活对静止和活跃的ISCs的影响。了解静止和活跃的ISCs的状态和命运的信号调节可以发现治疗肠道疾病的潜在靶点 疾病，包括癌症。如果这一目标能够实现，它不仅将为推进对ISC行为的研究开辟道路，也将为治疗肠道疾病开辟道路，在肠道疾病中，ISC驱动的组织再生是必不可少的，并将为筛选靶向癌症干细胞的药物开辟道路。识别、分离和鉴定ISCs的能力对于治疗的进步，特别是组织替代，以及对肠道疾病的发展、预防和治愈的进一步了解至关重要。

DESCRIPTION (provided by applicant): Characterized by continual turnover, the intestine provides an elegant system for the study of adult stem cells - - cells which self-renew and regenerate and, thus, hold great promise for regenerative medicine. Studies have provided important insight regarding the capacity of intestinal stem cells (ISCs) for self-repair or healing as well as ongoing maintenance and differentiation into all the various intestinal cell types. However, considerable research is needed to better understand the different states and functions of subpopulations of ISCs and how these are regulated. In other tissues, such as hair and blood, the quiescent stem cell subpopulation is known to be critical, especially for long-term maintenance of the stem cell pool and for regeneration in response to stress or injury. However, in intestine, it is a matter of debate whether bona fide quiescent ISCs exist and/or where they reside. This research proposes that bona fide quiescent ISCs coexist with active ISCs. The active subpopulation accounts for generation and regeneration of intestinal epithelial lineages, and the quiescent subpopulation functions as a 'reserve' pool to replenish lost active ISCs and damaged tissues. The goal of this research is to further investigate +4 quiescent ISCs, in particular, and to determine potential molecular regulation of quiescent and active ISC subpopulations. Methods to be used will include: surface markers and in vitro culture and in vivo lineage tracing assays to identify and characterize quiescent ISCs under stable and stressed conditions; RNA sequencing to determine how and where certain factors (Frizzled5 and/or 7) mediate signaling (noncanonical and/or canonical Wnt) that govern ISC maintenance, activation, self- renewal and location; and genetic mouse models to study the effect of protein inactivation on quiescent and active ISCs. Understanding signaling regulation of the state and fate of quiescent and active ISCs can uncover potential therapeutic targets for treating intestinal disorders, including cancer. If this goal can be achieved, it will open avenues not only for advancing the study of ISC behavior, but also for treating intestinal disorders in which ISC-driven tissue regeneration is essential and for screening drugs to target cancer stem cells. The ability to identify and isolate and characterize ISCs is critical for therapeutic advancements, especially tissue replacement, and for enhanced understanding of the development, prevention, and cure of intestinal disease.