Adrenal Regeneration: Stem Cells and Lineage Development

描述（由申请人提供）： 许多疾病状态由组织的损失或破坏引起，例如，胰岛细胞的丧失导致I型糖尿病，肾上腺皮质细胞的丧失导致阿狄森氏病。这些疾病的最终治疗将涉及（1）逆转破坏过程和（2）恢复正常组织。组织再生是将丢失或受损的组织恢复到正常状态的过程。调节这一动态和基本过程的机制仍然不完全清楚。两种主要机制包括（1）组织特异性成体干细胞和（2）谱系发育的调节，这可能涉及细胞分化、去分化和转分化。 采用经典的组织再生模型，小鼠肾上腺皮质，我们将调查这些基本过程。使用荧光激活细胞分选，我们将识别，分离和表征肾上腺祖细胞从动物经历了各种控制操作。然后将检查祖细胞在移植模型系统中的分化潜力。使用基因靶向方法和Cre-LoxP技术，我们将对小鼠肾上腺细胞进行遗传修饰，以进行谱系追踪和组织特异性敲除实验。这些实验旨在阐明肾上腺发育和分区的基本机制，并开始确定肾上腺再生的分子途径。 这项工作是在一个高度支持的环境中进行的，在每个主要领域的专业知识建议进行研究。此外，这项工作建立在PI的先前经验的基础上，通过结合基因靶向和Cre-LoxP技术的现代工具，产生转基因动物来研究基因表达和谱系发育。最后，通过将这项工作与作为儿科内分泌学家的有限临床责任（10%时间）相结合，PI将继续从临床接触中受益，这通常会导致对疾病机制的新见解。预计这项工作将使PI能够过渡到独立研究人员的职业生涯。

DESCRIPTION (provided by applicant): A number of disease states arise from the loss or destruction of tissue, e.g., loss of pancreatic islets cells results in Type I Diabetes and loss of adrenal cortical cells results in Addison's Disease. The ultimate treatment of these conditions would involve (1) reversal of the destructive process and (2) restoration of normal tissue. Tissue regeneration is the process by which lost or damaged tissue is restored to its normal state. The mechanisms, which regulate this dynamic and essential process, remain incompletely understood. Two major mechanisms include the regulation of (1) tissue-specific adult stem cells and (2) lineage development, which likely involves cellular differentiation, de-differentiation and trans-differentiation. Employing a classic model of tissue regeneration, the mouse adrenal cortex, we will investigate these fundamental processes. Using fluorescence activate cell sorting, we will identify, isolate and characterize adrenal progenitor cells from animals undergoing a variety of controlled manipulations. Progenitor cells will then be examined for their differentiation potential in transplantation model systems. Using a gene targeting approach and Cre-LoxP technology we will genetically modify mouse adrenal cells in order to perform lineage tracing and tissue-specific knockout experiments. These experiments are designed to elucidate fundamental mechanisms of adrenal development and zonation and begin to define the molecular pathway of adrenal regeneration. This work is being performed in a highly supportive environment with expertise in each major area proposed for study. Furthermore, this work builds upon the prior experiences of the PI, generating transgenic animals to study gene expression and lineage development, by incorporating the modern tools of gene targeting and Cre-LoxP technology. Finally, by combining this work with limited clinical responsibility (10% time) as a Pediatric Endocrinologist, the PI will continue to benefit from clinical encounters, which often lead to novel insights into the mechanisms of disease. It is expected that this work will be enable the PI to transition to a career as an independent researcher.