How Does a Young Extracellular Matrix Rejuvenate Old Mesenchymal Stem Cells?

年轻的细胞外基质如何​​使衰老的间充质干细胞恢复活力？

• 批准号: 8760208
• 负责人: XIAO-DONG CHEN
• 金额: --
• 依托单位: SOUTH TEXAS VETERANS HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-10-01 至 2017-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8760208
• 关键词: Adhesions; Adult; Age; Aging; Amino Acids; Apoptosis; Architecture; Atomic Force Microscopy; Autologous; Biological; Bone Marrow; Cell Aging; Cell Culture Techniques; Cell Lineage; Cell Proliferation; Cell Therapy; Cell physiology; Cells; Clinical; Collagen; Data; Defect; Disease; Elderly; Environmental Risk Factor; Exposure to; Extracellular Matrix; Failure; Foundations; Goals; Growth Factor; Health; Hematopoietic; Histocompatibility Testing; Human; Immunodeficient Mouse; In Vitro; Life; Maintenance; Marrow; Mechanics; Mesenchymal Stem Cells; Modeling; Modification; Molecular; Mus; Organ; Osteogenesis; Outcome; Patients; Play; Population; Positioning Attribute; Property; Proteins; Proteoglycan; Proteomics; Regulation; Relative (related person); Reporting; Role; Sampling; Scanning Transmission Electron Microscopy Procedures; Signal Transduction; Stable Isotope Labeling; Stem cells; Stromal Cells; Structure; Surveys; Target Populations; Testing; Therapeutic; Time; Tissues; Transplantation; Veterans; age effect; age related; aged; base; behavior influence; bone; cell age; cell behavior; functional restoration; human subject; improved; in vitro Model; in vivo; innovation; juvenile animal; migration; public health relevance; repaired; research study; response; self-renewal; senescence; theories

DESCRIPTION (provided by applicant): Bone marrow-derived mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into multiple cell lineages. Because of these capabilities, MSCs play an important role in continuous maintenance and repair of most tissue types. The quantity and quality of MSCs decrease with aging, which, in turn, is associated with the progressive failure of function of tissues and organs. Recently, we reported in mice that defects in the self-renewal and bone formation capacity of aged MSCs were completely restored by exposure to extracellular matrix (ECM) made by marrow stromal cells from young animals, and such improvement was substantially diminished when cells (from either young or old mice) were cultured on ECM made by old marrow stromal cells. This led us to investigate whether this phenomenon also occurs in humans. Indeed, our preliminary studies in human subjects clearly suggest that culturing aged MSCs on ECM made by young marrow stromal cells is able to improve their number and quality. The goal of this proposal is to determine the mechanisms whereby young ECM rejuvenates old bone marrow-derived MSCs. A unique, cell-free ECM model will be used to dissect how young ECM restores the functions of old MSCs in vitro and in vivo. The hypothesis proposed in this application is that age negatively impacts the formation of an ECM that normally preserves MSC function, and the quantity and quality of aged MSCs can be improved by exposure to an ECM made by stromal cells from young donors. We are uniquely-positioned to test this hypothesis in humans since, in addition to our strong preliminary data, up to 100 human bone marrow samples have been accumulated in the past three years from elders (60 to 96 years old). To test this hypothesis, we will systematically evaluate biological activities in viro and in vivo of young vs. old MSCs maintained on young- or old-ECM (Specific aim 1), and conduct proteomic analysis of young- and old-MSCs exposed to young- or old-ECM to elucidate the underlying changes at the protein level that are associated with the restored functions of the rescued cells (Specific aim 2). To fully understand the mechanisms underlying the influence of MSC behavior, we will determine the differences in the structures of young- vs. old-ECM including the architecture, mechanical properties, and protein composition (Specific aim 3). These studies are innovative in that we will have established, for the first time, a unique in vitr human model to examine effects of age on MSCs (intrinsic theory), and changes to MSCs by the surrounding ECM (extrinsic theory). Our studies are important from a translational point of view because they will provide key information that can facilitate the use of a patient's own (autologous) stem cells for cell- based therapies. In view of the fact that the elderly are the mai target population for this type of treatment, understating age-related changes in both MSCs and host is essential for improving the clinical outcome of transplanted autologous MSCs in old veteran.

描述（由申请人提供）： 骨髓间充质干细胞（MSC）能够自我更新并分化为多种细胞谱系。由于这些功能，间充质干细胞在大多数组织类型的持续维护和修复中发挥着重要作用。间充质干细胞的数量和质量随着年龄的增长而下降，这反过来又与组织和器官功能的逐渐衰竭有关。最近，我们在小鼠中报道，通过暴露于年轻动物的骨髓基质细胞产生的细胞外基质（ECM），衰老的MSC的自我更新和骨形成能力的缺陷完全恢复，而当细胞（来自年轻或年老的小鼠）在年老的骨髓基质细胞产生的ECM上培养时，这种改善大大减弱。这促使我们调查这种现象是否也发生在人类身上。事实上，我们对人类受试者的初步研究清楚地表明，在年轻骨髓基质细胞产生的 ECM 上培养老化的 MSC 能够提高其数量和质量。该提案的目标是确定年轻 ECM 使衰老的骨髓间充质干细胞恢复活力的机制。一种独特的无细胞 ECM 模型将用于剖析年轻 ECM 如何在体外和体内恢复老 MSC 的功能。本申请中提出的假设是，年龄对通常保留 MSC 功能的 ECM 的形成产生负面影响，并且可以通过暴露于由年轻供体的基质细胞产生的 ECM 来改善老化 MSC 的数量和质量。我们具有独特的优势，可以在人类身上检验这一假设，因为除了我们强有力的初步数据外，过去三年还从老年人（60 至 96 岁）收集了多达 100 个人类骨髓样本。为了检验这一假设，我们将系统地评估维持在年轻或年老ECM上的年轻与年老MSC的体外和体内生物活性（具体目标1），并对暴露于年轻或年老ECM的年轻和年老MSC进行蛋白质组学分析，以阐明与被拯救细胞功能恢复相关的蛋白质水平的潜在变化（具体目标2）。为了充分了解影响 MSC 行为的机制，我们将确定年轻 ECM 与老年 ECM 结构的差异，包括结构、机械性能和蛋白质组成（具体目标 3）。这些研究的创新之处在于，我们将首次建立一个独特的体外人体模型，以研究年龄对 MSC 的影响（内在理论），以及周围 ECM 对 MSC 的变化（外在理论）。从转化的角度来看，我们的研究很重要，因为它们将提供有助于使用患者自身（自体）干细胞进行细胞疗法的关键信息。鉴于老年人是此类治疗的主要目标人群，了解间充质干细胞和宿主与年龄相关的变化对于改善老年退伍军人移植自体间充质干细胞的临床效果至关重要。