Bone Marrow Derived Stromal Cells in Rat Models of Lung Injury

肺损伤大鼠模型中的骨髓衍生基质细胞

• 批准号: 7312546
• 负责人: Arnold Ralph Brody
• 金额: $ 32.94万
• 依托单位: TULANE UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7312546
• 关键词: asbestos; bone marrow; cell differentiation; cell population study; cell proliferation; disease /disorder model; fibroblasts; laboratory rat; lung injury; lung transplantation; mesenchyme; respiratory disorder epidemiology; respiratory epithelium; stem cell transplantation; stem cells; stromal cells; tissue /cell culture

This research is designed to test the central hypothesis that bone marrow-derived stromal stem cells engraft in the lung and differentiate to alveolar and airway epithelial and mesenchymal cells, consequently ameliorating or exacerbating the progression of fibroproliferative lung disease. Two well-characterized models of lung injury will be used: 1) Brief exposure to inhaled asbestos fibers rapidly causes injury of the bronchiolar-alveolar epithelium and a fibroproliferative lesion at the alveolar duct bifurcations. Studies were carried out in female rats that have undergone whole bone marrow transplantation from male green fluorescent protein (GFP)-transgenic syngeneic rats. The Preliminary Data shown here demonstrate that there are significantly increased numbers of GFP-positive, Y chromosome-positive bone marrow-derived cells in the asbestotic lesions compared with surrounding, uninjured tissues and with lungs from unexposed rats. Furthermore, the GFP-positive cells in the lung had both epithelial and mesenchymal phenotypes. Studies were also carried out in female rats injected intravascularly with 5 x 10[6] marrow stromal stem cells isolated from male GFP-transgenic rats. Our Preliminary Data demonstrate putative stem cells apparently attached to alveolar duct walls. Here we propose to define the subpopulations of stem cells that engraft and differentiate in injured lung and the effect they have on progression of asbestos-induced fibroproliferative lesions. 2) Denuded rat tracheae grafted into nude mice provide a milieu in which an epithelial lining can be reestablished, the characteristics of which is primarily determined by the differentiation potential of the inoculated cells. Our Preliminary Data show that purified populations of airway epithelial cells mixed with bone marrow-derived cells form a differentiated epithelium in the tracheal graft system. Furthermore the bone marrow-derived cells in the graft appear to differentiate into epithelial cells, as well as endothelial cells that participate in revascularization of the grafts. Some stem cells appear to differentiate as mesenchymal cells. This system will be ideal for testing the postulate since varying numbers of specific stem cell subpopulations in different stages of differentiation can be studied in combination with varying numbers and types of epithelial cells. There are no data available which allow us to predict whether or not the stem cells will play any role in the degree of lesion development or participate in populating the tracheo-bronchial and bronchiolar-alveolar duct walls. These studies will provide opportunities to develop therapeutic approaches through the use of adult bone marrow-derived stem cells because we know the precise anatomic and temporal distribution of the developing lesions. The stem cells will be characterized in, and we will be using the same populations of cells employed by investigators in the other projects. This will be a clear advantage for the final data analysis.

本研究旨在验证骨髓源性基质干细胞移植入肺并分化为肺泡和气道上皮细胞， 因此，本发明的方法可改善或加重纤维增生性肺病的进展。将使用两种充分表征的肺损伤模型：1）短暂暴露于吸入石棉纤维迅速导致细支气管肺泡上皮细胞损伤和肺泡管分叉处的纤维增生性病变。在接受了来自雄性绿色荧光蛋白（GFP）转基因同系大鼠的全骨髓移植的雌性大鼠中进行研究。这里显示的初步数据表明，在石棉肺病变中，GFP阳性、Y染色体阳性的骨髓源性细胞的数量显著增加， 周围未受伤的组织和未暴露大鼠的肺。此外，GFP阳性细胞在肺上皮和间充质表型。还在雌性大鼠中进行了研究，血管内注射5 × 10[6]从雄性GFP转基因大鼠中分离的骨髓基质干细胞。我们的初步数据表明，假定的干细胞显然附着在肺泡管壁。在这里，我们建议定义的干细胞亚群，在受伤的肺和石棉诱导的纤维增生性病变的进展的影响，他们的移植和分化。2)裸露的大鼠气管移植到裸鼠中提供了一个环境，在该环境中可以重建上皮衬里，其特征是 主要由接种细胞的分化潜能决定。我们的初步数据显示，纯化的气道上皮细胞群与骨髓来源的细胞混合，在气管移植系统中形成分化的上皮。此外，移植物中的骨髓来源的细胞似乎分化成上皮细胞，以及参与移植物血管再生的内皮细胞。一些干细胞似乎分化为间充质细胞。该系统将是理想的测试假设，因为不同数量的特定干细胞亚群在不同的分化阶段， 结合不同数量和类型的上皮细胞进行研究。目前还没有数据可以让我们预测干细胞是否会在肿瘤发生中发挥任何作用。 病变发展程度或参与气管支气管和细支气管肺泡管壁的填充。这些研究将提供机会，通过使用成人骨髓源性干细胞开发治疗方法，因为我们知道发展中病变的精确解剖和时间分布。干细胞将被表征，我们将使用与其他项目中研究人员使用的相同的细胞群。这对于最终的数据分析将是一个明显的优势。