Intravital analysis of hematopoietic stem cells in their bone marrow niche - Resubmission - 1

骨髓微环境中造血干细胞的活体分析 - 重新提交 - 1

• 批准号: 10491048
• 负责人: David R Fooksman
• 金额: $ 65.06万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-20 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10491048
• 关键词: Address; Adult; Affect; Animals; Behavior; Blood; Blood Vessels; Bone Marrow; Bone Marrow Stem Cell; Bone Marrow Transplantation; CXCL12 gene; CXCR4 Receptors; CXCR4 gene; Calcium; Calcium Signaling; Cellular Morphology; Clinic; Collaborations; Complex; Computer Analysis; Computer Models; Development; Enterobacteria phage P1 Cre recombinase; Environment; Genetic; Growth Factor; Hematopoiesis; Hematopoietic; Hematopoietic Stem Cell Mobilization; Hematopoietic stem cells; Hour; Immunity; Impairment; Inflammation; Inflammatory; Integrins; Interferons; Knowledge; Label; Mediator of activation protein; Molecular; Morphology; Mouse Strains; Mus; Natural regeneration; Nature; Pathologic; Pharmacology; Play; Process; Reporter; Role; Signal Transduction; Stem Cell Factor; Stem cell transplant; Stimulus; Stromal Cell-Derived Factor 1; Stromal Cells; System; Tamoxifen; Testing; Time; Transgenes; Transplantation; antagonist; behavioral study; cell behavior; cell motility; chemokine; clinically relevant; genetic analysis; genetic manipulation; hematopoietic stem cell niche; human old age (65+); in vivo; insight; intravital imaging; intravital microscopy; multiphoton imaging; multipotent cell; novel; peripheral blood; ratiometric; reconstitution; response; sensor; stem cell biology; stem cell function; stem cell growth; stem cell homeostasis

ABSTRACT Hematopoietic stem cells (HSC) in the adult mammalian bone marrow (BM) are rare multipotent cells that can regenerate and sustain multilineage hematopoiesis upon transplantation. Given the rarity and limited availability of HSC in the BM, strategies to "mobilize" HSC from the BM to the peripheral blood show great promise to enhance the efficiency of hematopoietic reconstitution. On the other hand, the reconstitution capacity of HSC can be impaired in old age or following inflammatory insults. HSC are localized in a unique functional BM compartment called the niche. Its key component is a network of perivascular stromal cells expressing the HSC growth factor stem cell factor (SCF or Kit ligand) and chemokine CXCL12, whose receptor CXCR4 helps retain HSC in the BM. However, the morphology and dynamics of endogenous live HSC and their interactions with the BM niche components have not been well characterized. We have developed a system for specific fluorescent labeling of adult murine HSC, and adapted it for intravital imaging of HSC within the BM. Preliminary studies revealed an unexpectedly dynamic morphology and complex motility of HSC in the steady state. Furthermore, we were able to visualize interactions between live HSC and the stromal cells. We will apply this system to systematically study the behavior of live HSC and their interaction with the niche in live animals. The project involves a collaboration between labs with the expertise in genetic manipulation and analysis of HSC (Reizis), intravital microscopy of the BM (Fooksman) and computational analysis and modeling of cell behavior (Krichevsky). In Aim 1, we will visualize the behavior of live HSC in the BM in the steady state and during inflammation. In Aim 2, we will characterize the interaction of HSC with their BM environment, both in normal conditions and after mobilization from the BM. In Aim 3, we will analyze the molecular basis of HSC dynamics and correlate it with HSC function in supporting hematopoiesis. The proposed studies would address major gaps in our knowledge of basic HSC biology, and provide novel insights into the clinically relevant process of HSC mobilization.

抽象的 成年哺乳动物骨髓 (BM) 中的造血干细胞 (HSC) 是罕见的多能细胞， 移植后可以再生并维持多系造血功能。鉴于其稀有性和有限性 BM 中 HSC 的可用性，将 HSC 从 BM“动员”到外周血的策略显示出巨大的优势 有望提高造血重建的效率。另一方面，重组 HSC 的能力在老年或炎症损伤后可能会受损。 HSC 本地化于独特的 功能性BM隔室称为利基。其关键组成部分是血管周围基质细胞网络 表达 HSC 生长因子干细胞因子（SCF 或 Kit 配体）和趋化因子 CXCL12，其 受体 CXCR4 有助于将 HSC 保留在 BM 中。然而，内源性活体的形态和动力学 HSC 及其与 BM 利基成分的相互作用尚未得到很好的表征。我们有 开发了一种对成年小鼠 HSC 进行特异性荧光标记的系统，并使其适用于活体内 BM 内 HSC 的成像。初步研究揭示了意想不到的动态形态和 HSC 在稳态下的复杂运动。此外，我们能够可视化之间的交互 活 HSC 和基质细胞。我们将应用这个系统来系统地研究活体HSC的行为 以及它们与活体动物生态位的相互作用。该项目涉及实验室之间的合作 HSC (Reizis) 基因操作和分析、BM 活体显微镜检查方面的专业知识 （Fooksman）以及细胞行为的计算分析和建模（Krichevsky）。在目标 1 中，我们将 可视化 BM 中活 HSC 在稳定状态和炎症期间的行为。在目标 2 中，我们将 表征 HSC 与其 BM 环境在正常条件下和之后的相互作用 来自BM的动员。在目标 3 中，我们将分析 HSC 动力学的分子基础并将其关联起来 具有HSC支持造血功能。拟议的研究将解决我们在 基础 HSC 生物学知识，并为 HSC 的临床相关过程提供新颖的见解 动员。