TRANSITION TO THE REPAIR FIBROBLAST PHENOTYPE

向修复成纤维细胞表型的转变

• 批准号: 2019840
• 负责人: M. Elizabeth Fini
• 金额: $ 48.19万
• 依托单位: TUFTS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-12-01 至 1998-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2019840
• 关键词: autocrine; collagenase; corneal epithelium; corneal stroma; enzyme induction /repression; enzyme inhibitors; extracellular matrix; eye regeneration; gene expression; growth inhibitors; interleukin 1; laboratory mouse; laboratory rabbit; molecular biology; molecular cloning; neutralizing antibody; phorbols; polymerase chain reaction; stromelysin; tissue /cell culture; wound healing

Recent interest in the use of surgical procedure to correct vision has resulted in renewed interest in mechanisms of stromal wound healing and remodelling. The lab goal is to elucidate molecular mechanisms activating quiescent stromal cells to initiate the deposition of repair tissue and to mediate subsequent repair tissue remodelling. Previous work indicates that stromal cell activation is controlled by an epithelial/stromal interaction. The matrix metalloproteinases, collagenase (CL) and stromelysin (SL) are expressed by stromal cells concomitant with their activation following corneal injury. Expression of these enzymes thus serves as a marker of the activation process and can be monitored to assay for controlling substances produced by the epithelium. Once activated, stromal cells develop competence to express CL/SL under autocrine control, and in response to agents which mimic aspects of signaling between cells and their extracellular matrix. Thus an investigation of the mechanisms that lead to development of competence for CL/SL expression can serve as a useful focus for defining the molecular changes that control the switch to the activated phenotype. Moreover, since CL/SL act as important mediators of repair tissue remodelling, studies along these lines would be expect to shed new light on regulation of the remodelling process. In preliminary studies a corneal epithelial stimulator of CL/SL expression was identified as the cytokine, IL-1alpha. In the current proposal, aspects of the molecular structure and expression of the corneal epithelial cytokine(s) inhibiting release of CL/SL by cultured stromal cells will also be characterized. The hypothesis that release of stimulatory cytokines, such as IL-1alpha, may be a common autocrine mechanism by which stromal interact reciprocally with their extracellular matrix to modulate expression of CL/SL will be tested. Steps in the molecular pathway leading to CL/SL stimulatory cytokine (I1-1alpha) expression and bioactivity will be examined. Finally, and most importantly, the role of I1-1alpha in controlling stromal cell activation and CL/Sl expression and modulation during corneal repair will be explored. This will be accomplished by measuring expression of I1-1alpha expression in repair tissue and correlating these results with those attempting to interfere with IL-1 activity in healing wounds by direct application, or transgenic expression, of an IL-1 antagonist.

最近人们对使用外科手术来矫正视力产生了兴趣 引起了人们对基质伤口愈合机制的新兴趣 重塑。 实验室的目标是阐明分子机制 激活静止的基质细胞以启动修复沉积 组织并介导随后的修复组织重塑。 以前的 研究表明基质细胞的激活是由 上皮/基质相互作用。 基质金属蛋白酶， 胶原酶 (CL) 和溶基质素 (SL) 由基质细胞表达 伴随着角膜损伤后的激活。 表达 因此，这些酶可以作为激活过程的标记， 可以进行监测以测定控制物质产生的物质 上皮。 一旦被激活，基质细胞就会发展出表达能力 CL/SL 在自分泌控制下，并对模仿的药物做出反应 细胞与其细胞外基质之间的信号传导方面。 因此 对导致能力发展的机制的调查 CL/SL 表达式可以作为定义 控制向激活表型转变的分子变化。 此外，由于 CL/SL 作为修复组织的重要介质 重塑，沿着这些思路的研究有望带来新的启示 关于改造过程的监管。 在初步研究中a CL/SL 表达的角膜上皮刺激物被确定为 细胞因子，IL-1α。 在当前的提案中，分子的各个方面 角膜上皮细胞因子抑制的结构和表达 培养的基质细胞释放 CL/SL 也将得到表征。 假设释放刺激性细胞因子，例如 IL-1α， 可能是基质相互作用的常见自分泌机制 与其细胞外基质相互作用来调节 CL/SL 将进行测试。 导致 CL/SL 的分子途径步骤 刺激性细胞因子（I1-1α）的表达和生物活性将 检查了。 最后，也是最重要的，I1-1alpha 在 控制基质细胞活化和 CL/Sl 表达和调节 在角膜修复期间将进行探索。 这将通过以下方式完成 测量修复组织中 I1-1α 的表达和 将这些结果与试图干扰 IL-1 的结果相关联 通过直接应用或转基因治愈伤口的活性 IL-1拮抗剂的表达。