FunctionalCharacterization of the Stem Cell Niche

干细胞生态位的功能表征

• 批准号: 8300198
• 负责人: Paul Hugo Krebsbach
• 金额: $ 36.09万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8300198
• 关键词: Acute; Address; Animals; Automobile Driving; Biological Models; Biology; Bone Marrow; Bone Regeneration; CD15 Antigens; Cell Communication; Cell Count; Cell Culture Techniques; Cell Differentiation process; Cell Separation; Cell physiology; Cell surface; Cells; Cellular biology; Complex; Data; Development; Developmental Biology; Dissection; Dose; Environment; Environmental Risk Factor; Exhibits; Family; Fluorouracil; Gelatin; Goals; Harvest; Health; Hematology; Hematopoietic stem cells; Hemorrhage; Immunohistochemistry; Immunophenotyping; Implant; In Vitro; Learning; Left; Life; Maps; Marrow; Mediating; Mesenchymal; Mesenchymal Stem Cells; Methods; Modeling; Monitor; Mononuclear; Mus; Nature; Osteoblasts; Osteogenesis; PTPRC gene; Pathologic; Phenotype; Physiological; Plastics; Pluripotent Stem Cells; Population; Principal Investigator; Process; Property; Research Personnel; Stem Cell Factor; Stem cells; Stimulus; Stress; Stromal Cells; System; Testing; Time; Tissue Engineering; Transgenic Organisms; Transplantation; acute stress; base; bone; bone morphogenetic protein 2; bone morphogenetic protein 6; cell type; design; flexibility; in vivo; in vivo Bioassay; in vivo Model; innovation; osteoblast differentiation; programs; prospective; reconstitution; response; scaffold; stem cell differentiation; stem cell fate; stem cell niche; stem cell population; subcutaneous; tool

DESCRIPTION (provided by applicant): We identified a partially purified mesenchymal stem cell (MSC) population that maintains its multi-lineage potential both in vivo and in vitro. Most importantly, we demonstrated that as few as 500 purified cells can develop bone in vivo without prior cell expansion in culture. This prospective isolation process, based upon lessons learned from hematology, sets us apart from others in the mesenchymal biology field and will allow us to understand the crucial differences in stem cell properties between cell culture and in vivo environments. The overall objective of this application is to understand the biology of this stem cell population, including in vivo lineage progression, how they function in the stem cell niche and determine the functional relationships and crosstalk between HSCs and MSCs. The central hypothesis behind our proposed projects is that a true mesenchymal stem cell exists within the bone marrow and the activity of this stem cell, including interactions with HSCs, is dependent on its niche compartment. We plan to test our central hypothesis and accomplish our objectives by pursuing three specific aims. Each aim offers the opportunity to generate new tools that will revolutionize the ability to discover and model the environmental factors that mediate cell function in complex in vivo systems such as the bone/bone marrow. Aim 1. To identify and characterize cells within the bone marrow stroma that exhibit mesenchymal stem cell activity. We will answer the following compelling questions: 1) Do these purified cells function as stem cells in vivo? 2) What is the capacity of these purified cells to function in their native in vivo micro-environment? and 3) How do MSCs respond to physiologic stimuli? Aim 2. To identify the MSC niche and determine the extent to which the MSC pool and its niche changes under physiologic and pathologic conditions (Mapping and defining the niche). We will address the following experimental questions 1) Where do MSCs reside within the marrow? 2) Do MSC numbers change in response to physiologic and or pathologic stimuli, including a single dose of 5-FU, a single acute bleed and anabolic PTH treatment? 3) Do perturbations of the marrow alter/regulate the MSC phenotype? Aim 3. To determine the functional relationships and cross talk between HSCs and MSCs. 1) Do MSCs and HSCs co-localize to the same niche? 2) Do HSCs (isolated with SLAM family markers) regulate MSC fate? PUBLIC HEALTH RELEVANCE: A fundamental question in cellular and developmental biology is how a stem cell niche develops, and how these niches support and maintain stem cell activity. We have pioneered the use of an in vivo model that we will now use to functionally characterize our prospectively isolated MSCs. Our projects are designed to understand the nature of these MSCs and how their microenvironment, including interactions with hematopoietic stem cells (HSCs), influences their biologic activity. The overall hypothesis driving our project is that a true mesenchymal stem cell exists within the bone marrow and the activity of this stem cell - including interactions with hematopoietic stem cells - is dependent on its niche compartment.

描述（由申请人提供）：我们鉴定了部分纯化的间充质干细胞（MSC）群体，其在体内和体外均保持其多谱系潜力。最重要的是，我们证明只需 500 个纯化细胞就可以在体内发育出骨骼，而无需事先在培养物中进行细胞扩增。这种基于血液学经验教训的前瞻性分离过程使我们在间充质生物学领域中脱颖而出，并使我们能够了解细胞培养和体内环境之间干细胞特性的关键差异。该应用的总体目标是了解该干细胞群的生物学，包括体内谱系进展、它们如何在干细胞生态位中发挥作用，并确定 HSC 和 MSC 之间的功能关系和串扰。我们提出的项目背后的中心假设是，骨髓内存在真正的间充质干细胞，并且该干细胞的活性（包括与造血干细胞的相互作用）取决于其生态位区室。我们计划通过追求三个具体目标来检验我们的中心假设并实现我们的目标。每个目标都提供了生成新工具的机会，这些新工具将彻底改变发现和模拟介导复杂体内系统（例如骨/骨髓）中细胞功能的环境因素的能力。目标 1. 鉴定和表征骨髓基质内表现出间充质干细胞活性的细胞。我们将回答以下引人注目的问题：1）这些纯化的细胞在体内是否具有干细胞的功能？ 2) 这些纯化细胞在其天然体内微环境中发挥作用的能力如何？ 3) MSCs 如何响应生理刺激？目标 2. 识别 MSC 生态位并确定 MSC 库及其生态位在生理和病理条件下变化的程度（映射和定义生态位）。我们将解决以下实验问题 1) MSC 驻留在骨髓内的哪里？ 2) MSC 数量是否会因生理和/或病理刺激（包括单剂量 5-FU、单次急性出血和合成代谢 PTH 治疗）而发生变化？ 3) 骨髓的扰动是否会改变/调节 MSC 表型？目标 3. 确定 HSC 和 MSC 之间的功能关系和串扰。 1) MSC 和 HSC 是否共定位于同一生态位？ 2) HSC（用 SLAM 家族标记分离）是否调节 MSC 命运？公共健康相关性：细胞和发育生物学的一个基本问题是干细胞生态位如何发育，以及这些生态位如何支持和维持干细胞活性。我们率先使用了体内模型，现在我们将使用该模型来对我们预期分离的 MSC 进行功能表征。我们的项目旨在了解这些 MSC 的性质以及它们的微环境（包括与造血干细胞 (HSC) 的相互作用）如何影响它们的生物活性。推动我们项目的总体假设是，骨髓内存在真正的间充质干细胞，并且该干细胞的活性（包括与造血干细胞的相互作用）取决于其生态位区室。

项目成果

Erythropoietin couples hematopoiesis with bone formation.

• DOI: 10.1371/journal.pone.0010853
• 发表时间: 2010-05-27
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Shiozawa Y;Jung Y;Ziegler AM;Pedersen EA;Wang J;Wang Z;Song J;Wang J;Lee CH;Sud S;Pienta KJ;Krebsbach PH;Taichman RS
• 通讯作者: Taichman RS

Prospective identification and skeletal localization of cells capable of multilineage differentiation in vivo.

• DOI: 10.1089/scd.2009.0445
• 发表时间: 2010-10
• 期刊: Stem cells and development
• 影响因子: 4
• 作者: Taichman RS;Wang Z;Shiozawa Y;Jung Y;Song J;Balduino A;Wang J;Patel LR;Havens AM;Kucia M;Ratajczak MZ;Krebsbach PH
• 通讯作者: Krebsbach PH