Angiogenesis in hyperoxic lung fibrosis

高氧肺纤维化中的血管生成

• 批准号: 6605174
• 负责人: IVOR Samuel DOUGLAS
• 金额: $ 12.62万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-30 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6605174
• 关键词: alveolar macrophages; angiogenesis; angiopoietins; blocking antibody; enzyme linked immunosorbent assay; hyperoxia; immunocytochemistry; laboratory mouse; northern blottings; phosphatidylinositol 3 kinase; pulmonary fibrosis /granuloma; serine threonine protein kinase; transfection; western blottings

DESCRIPTION (provided by applicant): This 5-year training program proposes the development plan for a career as an independent biomedical researcher in the area of lung injury and angiogenesis. The principal investigator, has completed Pulmonary and Critical Care Fellowship training through the ABIM Research Pathway. With the sponsors and experienced collaborators he will expand on his scientific skills in preparation for career progression as an independent physician-scientist. The program will emphasize skills in molecular biology of angiogenesis and macrophage regulation of fibrosis using a murine hyperoxia model. To advance his knowledge in computational biology he will attend courses in applied statistics. Steven Greenberg M.D. a macrophage biologist, and Paul Rothman M.D., a renowned immunologist in the area of molecular regulation of cytokine signaling, will provide sponsorship. The program will benefit from collaborative expertise of Jan Kitajewski PhD, an expert in angiogenesis and Patty Lee, M.D. who will provide consultative support for the hyperoxia studies. Additionally, George Yancopoulos, a world renowned investigator, will collaborate and serve with the sponsors, Drs. Kitajewski and Lee on an advisory committee every 8 weeks. This committee will review progress and provide close scientific support and career advice. Prolonged hyperoxia results in lung fibrosis in humans and mice. The accompanying vascular remodeling contributes to pulmonary hypertension, right heart failure, and premature death. This program addresses the questions: Do macrophage-derived angiogenic regulatory factors, particularly angiopoietin-2 (Ang-2), contribute to vascular remodeling in response to prolonged sublethal hyperoxia. Do these vascular alterations contribute, independently, to the development of lung fibrosis? And does macrophage-derived Ang-2 directly inhibit endothelial cell survival in response to hyperoxia? The role of macrophage-derived mediators in hyperoxic lung injury remains unclear. We demonstrate in preliminary experiments, increased Ang-2 mRNA and protein in response to hyperoxic exposure in RAW 264.7 and in a mouse model of sublethal hyperoxic lung fibrosis. These mice develop macrophage-predominant cellular infiltration, collagen deposition and pulmonary vascular regression that recapitulates features of subacute lung fibrosis in humans. The following specific aims will be accomplished: 1) The characterization of fibrotic and vascular remodeling responses in hyperoxia-exposed mice by immuno-histochemistry, Western and Northern blotting and ELISA to quantify changes in markers of lung fibrosis, angiogenesis and expression of angiogenic regulators and their receptors. The effects on pulmonary vasculature will be evaluated by confocal microscopy. 2) Functional changes in response to altered expression of macrophage-derived angiogenic regulators by angiogenesis assays. Macrophage-depleted mice will be used to assess the contribution of lung macrophages. 3) Lung targeted overexpression of Ang-1 or 2 by adenovirus transfection or blocking antibodies prior to hyperoxia to determine the contribution of Ang-2 to pulmonary vascular remodeling and fibrosis during prolonged sublethal hyperoxia. 4) Determine if Ang-2 mediated endothelial survival inhibition is PI3K/Akt dependent. Columbia University has an established record of successful mentorship and training for K08 Career awardees in their preparation for careers as independent.

描述（由申请人提供）： 这个为期5年的培训计划提出了作为肺损伤和血管生成领域的独立生物医学研究员的职业发展计划。 主要研究者已通过 ABIM 研究途径完成了肺部和重症监护奖学金培训。 在赞助商和经验丰富的合作者的帮助下，他将扩展自己的科学技能，为作为一名独立医师科学家的职业发展做好准备。 该计划将强调使用小鼠高氧模型进行血管生成和巨噬细胞纤维化调节的分子生物学技能。 为了提高他在计算生物学方面的知识，他将参加应用统计学课程。 巨噬细胞生物学家 Steven Greenberg 医学博士和细胞因子信号传导分子调控领域著名免疫学家 Paul Rothman 医学博士将提供赞助。 该计划将受益于血管生成专家 Jan Kitajewski 博士和医学博士 Patty Lee 的合作专业知识，后者将为高氧研究提供咨询支持。 此外，世界著名的研究者 George Yancopoulos 将与赞助商 Drs. 合作并服务。 Kitajewski 和 Lee 每 8 周就加入一个咨询委员会。 该委员会将审查进展情况并提供密切的科学支持和职业建议。 长期高氧会导致人和小鼠的肺纤维化。 伴随的血管重塑导致肺动脉高压、右心衰竭和过早死亡。 该计划解决了以下问题：巨噬细胞衍生的血管生成调节因子，特别是血管生成素-2 (Ang-2)，是否有助于响应长期亚致死高氧的血管重塑。 这些血管改变是否独立地导致肺纤维化的发展？ 巨噬细胞衍生的 Ang-2 是否会直接抑制内皮细胞对高氧反应的存活？ 巨噬细胞衍生的介质在高氧性肺损伤中的作用仍不清楚。 我们在初步实验中证明，在 RAW 264.7 和亚致死高氧肺纤维化小鼠模型中，Ang-2 mRNA 和蛋白质响应高氧暴露而增加。 这些小鼠出现以巨噬细胞为主的细胞浸润、胶原沉积和肺血管退化，再现了人类亚急性肺纤维化的特征。 将实现以下具体目标： 1) 通过免疫组织化学、Western 和 Northern 印迹以及 ELISA 来表征高氧暴露小鼠的纤维化和血管重塑反应，以量化肺纤维化标记物、血管生成和血管生成调节剂表达的变化。他们的受体。 将通过共聚焦显微镜评估对肺血管系统的影响。 2)通过血管生成测定，响应巨噬细胞衍生的血管生成调节因子表达改变的功能变化。 巨噬细胞耗尽的小鼠将用于评估肺巨噬细胞的贡献。 3)在高氧之前通过腺病毒转染或阻断抗体来靶向肺过度表达Ang-1或2，以确定Ang-2在长时间亚致死高氧期间对肺血管重塑和纤维化的贡献。 4) 确定 Ang-2 介导的内皮存活抑制是否依赖于 PI3K/Akt。 哥伦比亚大学在为 K08 职业获奖者提供成功指导和培训方面有着良好的记录，帮助他们为独立职业做好准备。