Slowly cycling cells and hair follicle stem cells

缓慢循环细胞和毛囊干细胞

• 批准号: 7275617
• 负责人: Tudorita Tumbar
• 金额: $ 1.59万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-16 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7275617
• 关键词: Mus musculus; cell differentiation; cell growth regulation; cell sorting; gene expression; genetically modified animals; hair follicle; microarray technology; regeneration; skin; stem cells; tissue /cell culture; wound healing

DESCRIPTION (provided by applicant): We are interested in elucidating the molecular mechanisms involved in tissue stem cell self-renewal and fate choice, in normal tissue development and homeostasis. Stem cells hold great promises for future therapies of numerous deadly diseases, yet their basic properties are not well understood. Progress in the field has been hampered by the difficulty of identifying tissue stem cells in the absence of specific biochemical markers. Increasing evidence suggested that stem cells are infrequently dividing cells, that could be identified in many mouse tissues as DMA label retaining cells (or LRCs). Recently we developed a strategy applicable to many self-regenerating tissues to pulse-label LRCs with the green fluorescent protein (GFP) fused to histone H2B. We have used the mouse skin and the hair follicle as model systems, since the relation between LRCs and skin epithelial stem cells had been investigated in most depth. In our preliminary work we tracked and isolated GFP LRCs and demonstrated that at least a fraction of these cells had a stem cell phenotype. In this proposal we describe in three Specific Aims strategies to examine in more detail the relation between LRCs and stem cells. We will: 1) classify LRCs into distinct sub- populations and investigate their sternness; 2) examine their special cell cycle properties; 3) characterize their distinct patterns of gene expression. To accomplish these goals we use in vivo cell tracking and in vitro cell sorting methods combined with a variety of assays which include: hair regeneration and skin wounding; cell culture and skin reconstitution; cell cycle kinetics; and microarrays. First, our data will have global relevance for the isolation and characterization of putative stem cells with LRCs properties from many tissues. Although we focus on the skin, our work will lead the way for similar approaches in many systems which lack the specific means to separate stem cells from other cells of their tissue of residence. Second, stem cell proliferation must be tightly controlled in tissues to regulate the balance between normal and abnormal growth. Our studies will unravel some of the mechanisms developed by putative SCs to control their proliferation, an important first step in understanding such perturbation in the diseased tissues. Finally, our work will provide some of the basic knowledge necessary for more efficient manipulation of skin stem cells for clinical applications such as cell transplantation on burn victims.

描述(申请人提供)：我们感兴趣的是阐明组织干细胞自我更新和命运选择的分子机制，以及正常组织发育和动态平衡的分子机制。干细胞为许多致命疾病的未来治疗带来了巨大的希望，但它们的基本特性还没有被很好地了解。该领域的进展一直受到在缺乏特定生化标记的情况下识别组织干细胞的困难的阻碍。越来越多的证据表明，干细胞是很少分裂的细胞，在许多小鼠组织中可以被识别为DMA标记保留细胞(或LRC)。最近，我们发展了一种适用于许多自再生组织的策略，用融合到组蛋白H2B的绿色荧光蛋白(GFP)脉冲标记LRCs。我们使用小鼠皮肤和毛囊作为模型系统，因为LRCs和皮肤上皮干细胞之间的关系已经被深入研究。在我们的前期工作中，我们跟踪并分离了GFP LRC，并证明了这些细胞中至少有一部分具有干细胞表型。在这项提案中，我们在三个具体目标中描述了更详细地检查LRCs和干细胞之间的关系的策略。我们将：1)将LRC分为不同的亚群，并研究它们的严肃性；2)检查它们特殊的细胞周期特性；3)表征它们不同的基因表达模式。为了实现这些目标，我们使用体内细胞跟踪和体外细胞分选方法，并结合各种检测方法，包括：毛发再生和皮肤损伤；细胞培养和皮肤重建；细胞周期动力学；以及微阵列。 首先，我们的数据将对从许多组织中分离和表征具有LRCs特性的假定干细胞具有全球相关性。尽管我们专注于皮肤，但我们的工作将在许多系统中引领类似的方法，这些系统缺乏将干细胞从其居住组织的其他细胞中分离出来的具体方法。其次，必须严格控制组织中的干细胞增殖，以调节正常和异常生长之间的平衡。我们的研究将揭开一些可能的干细胞控制其增殖的机制，这是了解疾病组织中这种扰动的重要第一步。最后，我们的工作将提供一些必要的基本知识，以便更有效地操作皮肤干细胞，用于临床应用，如烧伤患者的细胞移植。