Skin Stem Cells: Purification and Characterization

项目摘要 这项研究的总体目标是阐明组织动态平衡和 哺乳动物皮肤的再生，并了解这一过程如何在人类疾病中出错，包括 癌症。实现这一目标的核心是对皮肤中不同的干细胞(SCs)进行表征， 确定它们对组织动态平衡和伤口修复的相对贡献，并阐明它们是如何变化的 在利基微环境中影响这些事件。过去的AR050452研究导致了毛囊的净化 (HF)隆起和基本的毛囊间表皮(EPD)细胞，并建立它们为长期的、自我更新的细胞 在组织再生和伤口修复中起作用的干细胞。然而，无论是在生物学上还是在组织上 再生任务，这些SC显示出不同的行为，这些行为似乎是基于其独特的 微环境(生态位)。该领域仍然缺乏对这些利基的组成的全面了解， 干细胞的性质：利基相互作用，以及它们如何帮助干细胞应对压力情况。过去的AR050452 研究已经为解决以下关键问题奠定了基础：(1)。哪些是利基组件 以及它们如何随毛发周期变化？(2)EPD-和HF-的相对贡献是什么？ SCS到伤口修复？这在浅层伤口和深层伤口上有区别吗？在年轻小鼠和老年小鼠中？(3)什么是 损伤和衰老引起的SC-NICE串扰的变化及其生理意义 相关性？(4)供应链如何应对和协调修复其利基壁垒中的局部漏洞？哪一个 细胞将损伤信号传递给周围的免疫细胞，它们是如何被触发这样做的？做什么 干细胞存活？(5)干细胞如何在毛发周期结束时保护自己，当大部分HF经历 细胞凋亡与终末分化？为了回答这些问题，我们将使用FACS，单细胞RNA序列，芯片- SEQ、条件基因敲除和RNAi体内筛选及应用这些方法探索皮肤干细胞 在它们的原生、突变和创伤诱导的环境中。

Project Summary The global objective of this research is to elucidate the mechanisms underlying tissue homeostasis and regeneration in mammalian skin and to understand how this process goes awry in human disorders, including cancers. Central to achieving this goal is the characterization of the different stem cells (SCs) within skin, determining their relative contributions to tissue homeostasis and wound-repair, and elucidating how changes in niche microenvironments impact these events. Past AR050452 research led to purification of hair follicle (HF) bulge and basal inter-follicular epidermal (Epd) cells, and established them as long-lived, self-renewing SCs that function in tissue regeneration and wound-repair. However, both in their biology and their tissue regenerative tasks, these SCs display distinct behaviors that appear to be predicated on their unique microenvironments (niches). The field still lacks a comprehensive knowledge of the constituents of these niches, the nature of SC:niche interactions, and how they help stem cells cope with stressful situations. Past AR050452 research has set the foundations to tackle the following key questions: (1). What are the niche components of HFSCs and how do they change with the hair cycle? (2) What are the relative contributions of Epd- and HF- SCs to wound repair? Does this differ in superficial vs deep wounds? In young vs aging mice? (3) What are the changes in SC-niche crosstalk that occur in response to injury and aging and what is their physiological relevance? (4) How do SCs respond to and orchestrate the repair of local breaches in their niche barrier? Which cells transmit damage signals to the surrounding immune cells and how are they triggered to do so? How do SCs survive? (5) How do SCs protect themselves at the end of the hair cycle, when the bulk of the HF undergoes apoptosis and terminal differentiation? To answer these questions, we’ll use FACS, single cell RNA-seq, ChIP- seq, conditional gene knockout and RNAi screens in vivo and employ these methods to explore skin stem cells in their native, mutant and wound-induced environments.