Gradient biomaterials to investigate niche regulation of hematopoiesis

梯度生物材料研究造血的生态位调节

• 批准号: 10413538
• 负责人: Brendan A. Harley
• 金额: $ 9.98万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2023-07-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10413538
• 关键词: Address; Automobile Driving; Benchmarking; Biocompatible Materials; Biological Assay; Biology; Biomimetics; Biophysics; Blood; Blood Vessels; Bone Marrow; Bone Marrow Transplantation; Cells; Communities; Complement; Ecosystem; Encapsulated; Engineering; Extracellular Matrix; Funding; Future; Goals; Gold; Hematology; Hematopoiesis; Hematopoietic Stem Cell Transplantation; Hematopoietic System; Hematopoietic stem cells; Hydrogels; Hypoxia; Immune; In Vitro; Infrastructure; Investigation; Kinetics; Life; Machine Learning; Marrow; Mediating; Medicine; Metabolic; Modeling; Mus; Pattern; Pericytes; Physiological; Process; Regulation; Research; Signal Transduction; Stress; Structure; Technology; Therapeutic; Tissue Engineering; arteriole; base; cell behavior; design; exhaustion; extracellular; hematopoietic stem cell expansion; hematopoietic stem cell fate; hematopoietic stem cell niche; hematopoietic stem cell quiescence; in vivo; innovation; intercellular communication; nanolitre; pressure; programs; response; self-renewal; stem cells; stemness; tool

ABSTRACT Replicating the cascade of signals responsible for controlling stem cell behavior remains a critical challenge for biology and medicine. Hematopoiesis is the process where the body’s blood and immune cells are generated from a small number of hematopoietic stem cells (HSCs). HSC quiescence, self-renewal, and differentiation take place in, and are regulated by, unique regions of the bone marrow termed niches. HSCs are also the functional unit of therapeutic bone marrow transplants following myeloablative therapies. A major goal of the hematology community is to selectively expand HSCs without sacrificing a subpopulation of quiescent, long-term repopulating HSCs required for life-long hematopoiesis. Perivascular niches (PVNs) within the bone marrow are increasingly believed to present a constellation of matrix, biomolecular, and metabolic signals to support HSC expansion and quiescence, however their rarity and complexity can complicate direct in vivo examination. The long-term goal of this Stimulating Hematology Investigation – New Endeavors (SHINE) project is to advance a tissue engineering platform to achieve HSC expansion without exhaustion. In the previous funding period (R01DK099528), we established a tissue engineering ecosystem to examine the coordinated impact of niche- inspired biophysical signals and marrow-derived niche cells on HSC fate. We showed the kinetics of HSC-niche cell crosstalk can be manipulated via biomaterial design to dramatically alter HSC fate decisions. And we developed machine learning tools to identify secretome signals generated by niche-associated MSCs that enhance retention of quiescent HSCs. We build on these findings to investigate the coordinated effect of multicellular crosstalk, cell-mediated extracellular matrix remodeling, and hypoxic stress within the perivascular niche using biomimetic models of marrow sinusoidal vs. arteriolar vascular niches. The overall objective of this project is to define patterns of multicellular signaling and remodeling within an engineered PVN biomaterial in order to identify synthetic niches that promote HSC expansion without exhaustion. To address this goal we will first construct and thoroughly characterize an engineered perivascular niche (Aim 1). We will subsequently resolve patterns of niche remodeling and HSC-PVN crosstalk in response to hypoxia (Aim 2). And we will establish a microdroplet-based artificial marrow niche to encapsulate single murine HSCs in nanoliter-volume hydrogel droplets (Aim 3). Throughout, we will benchmark patterns of in vitro HSC expansion via the gold standard in vivo competitive repopulation assay. This proposed research is unified in our focus to use the well- characterized murine hematopoietic system to develop engineered niche technologies for HSC expansion. Consistent with score-driving criteria of the SHINE program, we will generate innovative tissue engineering infrastructure to define dynamic processes of remodeling and intercellular HSC-niche crosstalk necessary to achieve durable HSC expansion without exhaustion.

摘要 复制负责控制干细胞行为的信号级联仍然是生物学和医学的关键挑战。造血是身体的血液和免疫细胞从少量造血干细胞（HSC）产生的过程。HSC的静止、自我更新和分化发生在称为小生境的骨髓的独特区域中，并受其调节。HSC也是清髓性治疗后治疗性骨髓移植的功能单位。血液学界的一个主要目标是选择性扩增HSC，而不牺牲终生造血所需的静止、长期再增殖的HSC亚群。骨髓内的血管周围小生境（PVN）越来越被认为呈现一系列基质、生物分子和代谢信号以支持HSC扩增和静止，然而它们的稀有性和复杂性会使直接体内检查复杂化。这个刺激血液学研究-新努力（SHINE）项目的长期目标是推进组织工程平台，以实现HSC的无疲惫扩张。在上一个资助期（R 01 DK 099528），我们建立了一个组织工程生态系统，以检查小生境激发的生物物理信号和骨髓来源的小生境细胞对HSC命运的协调影响。我们表明，HSC-小生境细胞串扰的动力学可以通过生物材料设计来操纵，以显著改变HSC的命运决定。我们开发了机器学习工具来识别由小生境相关MSC产生的分泌组信号，这些信号增强了静止HSC的保留。我们建立在这些研究结果的协调作用，多细胞串扰，细胞介导的细胞外基质重塑，和缺氧应力内的血管周围的生态位使用骨髓窦与微动脉血管生态位的仿生模型。该项目的总体目标是定义工程PVN生物材料内的多细胞信号传导和重塑模式，以确定促进HSC扩增而不耗尽的合成小生境。为了实现这一目标，我们将首先构建和彻底表征工程血管周围生态位（目标1）。随后，我们将解决响应缺氧的小生境重塑和HSC-PVN串扰的模式（目的2）。我们将建立一个基于微滴的人工骨髓龛，将单个鼠HSC封装在纳升体积的水凝胶微滴中（目标3）。在整个过程中，我们将通过体内竞争性再增殖试验的金标准，在体外HSC扩增的基准模式。这项研究的重点是利用小鼠造血系统的特点，开发造血干细胞扩增的工程利基技术。与SHINE计划的分数驱动标准一致，我们将产生创新的组织工程基础设施，以定义重塑和细胞间HSC-生态位串扰的动态过程，这些过程是实现持久HSC扩增而不耗尽所必需的。