Skeletal Stem Cell PDGFR-beta Signaling as a New Regulator of the HSC Niche

骨骼干细胞 PDGFR-β 信号传导作为 HSC 生态位的新调节器

• 批准号: 10001333
• 负责人: Hae Ryong Kwon
• 金额: $ 6.74万
• 依托单位: OKLAHOMA MEDICAL RESEARCH FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10001333
• 关键词: Abnormal Platelet; Address; Adipocytes; Adult; Alleles; Anemia; Biological Assay; Blood; Blood Tests; Bone Marrow; Bone Marrow Cells; Bone Marrow Transplantation; Cardiovascular Diseases; Cell Lineage; Cell Maintenance; Cell physiology; Cells; Chondrocytes; Chondrogenesis; Chromosome abnormality; Colony-Forming Units Assay; Colony-forming units; Coupled; DNA Sequence Alteration; Data; Defect; Development; Disease; Engraftment; Environment; Evaluation; Fibroblasts; Fibrosis; Flow Cytometry; Gene Expression Profiling; Genetic; Goals; Growth Factor; Hematologic Neoplasms; Hematology; Hematopoiesis; Hematopoietic; Hematopoietic Neoplasms; Hematopoietic Stem Cell Specification; Hematopoietic stem cells; Homeostasis; Image; In Vitro; Instruction; JAK2 gene; Kidney; Knock-in; Knowledge; Leukemic Cell; Life; Maintenance; Malignant Neoplasms; Marrow; Mediating; Medicine; Mesenchymal Stem Cells; Multipotent Stem Cells; Mus; Mutant Strains Mice; Mutation; Myelofibrosis; Myeloproliferative disease; Neoplasms; Oncogenic; Organogenesis; Osteoblasts; Osteogenesis; PDGFRB gene; Pathology; Phenotype; Platelet-Derived Growth Factor; Platelet-Derived Growth Factor Receptor; Platelet-Derived Growth Factor alpha Receptor; Platelet-Derived Growth Factor beta Receptor; Process; Production; Receptor Activation; Receptor Signaling; Regulation; Reporting; Research Project Grants; Role; Signal Transduction; Stromal Cells; Supporting Cell; Syndrome; Tamoxifen; Testing; Tissues; Transplantation; Treatment Efficacy; Wild Type Mouse; Work; blood formation; bone; capsule; cell transformation; cytokine; driving force; experimental study; gain of function; genetic approach; genetic manipulation; hematopoietic stem cell expansion; hematopoietic stem cell niche; hematopoietic stem cell self-renewal; human disease; improved; in vivo; insight; leukemia; lipid biosynthesis; mouse Cre recombinase; mouse genetics; mouse model; mutant; novel; organ growth; postnatal; receptor; regenerative; self-renewal; skeletal; stem cells; stemness; targeted treatment; therapeutic target

PROJECT SUMMARY/ABSTRACT Platelet-derived growth factor (PDGF) and its corresponding receptors (PDGFRα and PDGFRβ) regulate organogenesis and tissue homeostasis. Abnormal receptor signaling has been implicated in developmental syndromes and adult diseases such as fibrosis, cardiovascular disease, and cancer. Therefore, PDGF receptor activation and its downstream signaling have been proposed as potential therapeutic targets. Recent reports have implicated PDGFRβ signaling in regulating bone marrow (BM) microenvironment and hematopoietic stem cell (HSC) maintenance. Although skeletal stem cells (SSCs) are known to express PDGFRβ, a regulatory role of PDGFRβ in HSC niche is unknown. Our goal is to determine the roles of PDGFRβ in HSC niche maintenance and SSC function. Our central hypothesis is that PDGFRβ signaling in SSCs regulates the size of the HSC niche and blood-forming functions of the BM. With our expertise in PDGF signaling and novel genetic approaches, this project will address the central hypothesis with the two following aims: 1) Characterize the impact of SSC PDGFRβ signaling on the HSC pool maintenance and myeloproliferative neoplasia (MPN) development and 2) Define the functional consequences on SSCs/stromal lineages with altered PDGFRβ signaling. In Aim 1, tamoxifen-inducible Gli1 Cre recombinase mouse line (Gli1-CreER) will be used to conditionally induce a gain-of-function PDGFRβ knock-in allele or to inactivate the endogenous Pdgfrb gene in Gli1+ SSCs. Experiments using WT and mutants will focus on the evaluation of functional changes in BM and blood with altered PDGFRβ in SSCs. We will transplant BM from PDGFRβ mutants to irradiated wild type (WT) mice (or vice versa) to determine the extent at which blood forming cells acquire permanent functional alterations from the PDGFRβ mutant environment. Finally, we will determine whether altered PDGFRβ- regulated stromal environment alters MPN progression using BM transplantation with JAK2-V617F mutant BM cells. In Aim 2, in order to characterize cellular changes and functionality in HSC niche-supportive SSCs and stromal lineages in PDGFRβ mutants, we will use in vitro SSC assays to evaluate functional changes in SSC stemness, differentiation, and cytokine production. Finally, SSCs sorted from BM of PDGFRβ mutants or controls will be transplanted into WT kidney capsules to determine the impact of SSC PDGFRβ signaling on the modulation of BM formation and HSC colonization in vivo. The results of these projects will generate new knowledge of PDGFRβ signaling-mediated stroma-to-HSC niche crosstalk and facilitate the development of potential therapeutic targets on BM and hematopoietic diseases.

项目总结/摘要 血小板衍生生长因子（PDGF）及其相应受体（PDGFRα和PDGFRβ）调节 器官发生和组织内稳态。异常的受体信号传导与发育有关， 综合症和成人疾病，如纤维化、心血管疾病和癌症。因此，PDGF受体 激活及其下游信号传导已被提出作为潜在的治疗靶点。最近的报告 PDGFRβ信号通路参与调节骨髓微环境和造血干细胞 细胞（HSC）维持。虽然已知骨骼干细胞（SSC）表达PDGFRβ，但其调节作用是通过调节细胞增殖来实现的。 PDGFRβ在HSC小生境中的表达尚不清楚。我们的目标是确定PDGFRβ在HSC小生境中的作用 维护和SSC功能。我们的中心假设是，精原干细胞中的PDGFRβ信号调节了细胞的大小。 造血干细胞生态位和骨髓造血功能。凭借我们在PDGF信号传导和新型遗传学方面的专业知识， 方法，本项目将解决中心假设与以下两个目标：1）表征 SSC PDGFRβ信号对HSC池维持和骨髓增生性肿瘤（MPN）的影响 2）定义PDGFRβ改变对SSC/基质谱系的功能影响 发信号。在目标1中，他莫昔芬诱导的Gli 1 Cre重组酶小鼠系（Gli 1-CreER）将用于 有条件地诱导功能获得性PDGFRβ基因敲入等位基因或使内源性Pdgfrb基因失活， Gli1+ SSC。使用WT和突变体的实验将集中于评估BM和BLM中的功能变化。 SSC中PDGFRβ改变的血液。我们将从PDGFRβ突变体中移植BM到辐照野生型（WT）中， 小鼠（或反之亦然），以确定造血细胞获得永久功能的程度 PDGFRβ突变体环境的改变。最后，我们将确定改变的PDGFRβ- 使用具有JAK 2-V617 F突变BM的BM移植，调节的基质环境改变MPN进展 细胞在目的2中，为了表征HSC小生境支持性SSC中的细胞变化和功能， 我们将使用体外SSC测定来评估SSC在PDGFRβ突变体中的功能变化， 干性、分化和细胞因子产生。最后，从PDGFRβ突变体或 将对照移植到WT肾胶囊中，以确定SSC PDGFRβ信号传导对 BM形成和HSC在体内定殖的调节。这些项目的成果将产生新的 PDGFRβ信号介导的基质-HSC生态位串扰的知识，并促进 BM和造血系统疾病的潜在治疗靶点。