G-CSF RECEPTOR AND PROGENITOR MOBILIZATION

G-CSF 受体和祖细胞动员

• 批准号: 6390000
• 负责人: Daniel C Link
• 金额: $ 21.77万
• 依托单位: BARNES-JEWISH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6390000
• 关键词: attenuated microorganism; biological signal transduction; bone marrow transplantation; cathepsin G; cell cycle; cell differentiation; cell migration; cell motility; cell type; chimeric proteins; colony stimulating factor; cyclophosphamide; diphtheria toxin; erythropoietin; flow cytometry; gene expression; gene mutation; genetically modified animals; growth factor receptors; hematopoiesis; hematopoietic growth factor; hematopoietic stem cells; interleukin 12; laboratory mouse; neutrophil; transfection

The long range objective of this research is to characterize the molecular mechanisms involved in hematopoietic progenitor cell (HPC) mobilization. The use of HPC to reconstitute hematopoiesis following myeloablative therapy has significantly improved the clinical outcome in patients with a variety of malignancies. Recently, mobilized peripheral blood HPC instead of bone marrow-derived HPC have been used because of their reduce engraftment times, relative ease of collection, and possibly reduced risk of graft-versus-host disease. Currently to mobilize HPC from the bone marrow to blood are well tolerate but not universally effective and are often associated with co-mobilization of neoplastic cells. A better understanding of the mechanisms that regulate HPC mobilization may lead to the design of novel mobilization strategies that overcome these problems. We recently showed that mobilization of HPC in response to cyclophosphamide (CY) or interleukin-8 but not fit-3 ligand is markedly impaired in granulocyte colony-stimulating factor receptor (G-CSFR) deficient mice. These surprising results suggested that G-CSFR signals in hematopoietic- or bone marrow stromal-cells play an important and previously unexpected role in HPC migration. This proposal is designed to characterize these these G- CSFR-dependent mechanisms of HPC mobilization. The following specific aims are proposed. 1. We will characterize in detail the mobilization response in G-CSFR deficient mice to CY, interleukin-12 (IL-12), or stem cell factor (SCF).. HPC mobilization in G-CSFR deficient mice in response to SCF or IL-12 will be analyzed. To explore mechanisms for the mobilization defect in G- CSFR deficient mice, the phenotype of hematopoietic cells, in particular HPC , in the bone marrow of wild-type versus G-CSFR deficient mice after CY treatment will be compared. 2. We will identify the cell type responsible for G-CSFR dependent mobilization. Preliminary studies of HPC mobilization in G-CSFR deficient radiation chimeras suggest that a functional G-CSFR on mature hematopoietic cells but not on HPC or stromal cells is required for CY- induced mobilization. The first objective of this specific aim is to confirm these surprising results and to determine whether primitive HPC are mobilized in a similar fashion. The second objective of this specific aim is to characterize G-CSF induced mobilization in these radiation chimeras. 3. We will define the role of neutrophils in G-CSFR dependent mobilization. A neutropenic mouse line will be generated by driving expression of the attenuated diphtheria toxin A subunit in myeloid cells using murine cathepsin G regulatory sequences. CY- and G-CSF induced HPC mobilization will be characterized in these mice. 4. We will define the regions of the G-CSFR that are required for HPC mobilization. CY- and G-CSF-induced mobilization will be characterized in two recently generated targeted "knock-in" mutations of the G-CSFR. The role of STAT-3 in the generation of the HPC mobilization signal by the G- CSFR will be examined.

本研究的长期目标是表征造血祖细胞（HPC）动员的分子机制。在清髓性治疗后使用HPC重建造血已显著改善多种恶性肿瘤患者的临床结局。 最近，动员的外周血HPC代替骨髓来源的HPC已被使用，因为它们减少了植入时间，相对容易收集，并可能降低移植物抗宿主病的风险。目前，动员HPC从骨髓到血液是耐受性良好，但不是普遍有效的，往往与肿瘤细胞的共动员。更好地了解调节HPC动员的机制可能会导致设计新的动员策略，克服这些问题。我们最近发现，动员HPC响应环磷酰胺（CY）或白细胞介素-8，但不适合-3配体显着受损的粒细胞集落刺激因子受体（G-CSFR）缺陷小鼠。这些令人惊讶的结果表明，造血或骨髓基质细胞中的G-CSFR信号在HPC迁移中发挥重要且先前意想不到的作用。该提议旨在表征HPC动员的这些G-CFR依赖性机制。提出了以下具体目标。1.我们将详细描述G-CSFR缺陷小鼠对CY、白细胞介素-12（IL-12）或干细胞因子（SCF）的动员反应。将分析G-CSFR缺陷小鼠中响应于SCF或IL-12的HPC动员。为了探索G-CSFR缺陷小鼠中动员缺陷的机制，将比较CY处理后野生型与G-CSFR缺陷小鼠骨髓中造血细胞，特别是HPC的表型。2.我们将确定负责G-CSFR依赖性动员的细胞类型。在G-CSFR缺陷的辐射嵌合体中HPC动员的初步研究表明，CY诱导的动员需要成熟造血细胞上而不是HPC或基质细胞上的功能性G-CSFR。这个特定目标的第一个目标是确认这些令人惊讶的结果，并确定是否原始HPC以类似的方式动员。该特定目的的第二个目的是表征这些辐射嵌合体中G-CSF诱导的动员。3.我们将确定中性粒细胞在G-CSFR依赖性动员中的作用。将通过使用鼠组织蛋白酶G调节序列驱动减毒白喉毒素A亚基在骨髓细胞中的表达来产生血小板减少小鼠系。将在这些小鼠中表征CY和G-CSF诱导的HPC动员。4.我们将定义HPC动员所需的G-CSFR区域。CY-和G-CSF-诱导的动员将在两个最近产生的靶向“敲入”突变的G-CSFR的特点。将检查STAT-3在G-CSFR产生HPC动员信号中的作用。