P53, APOPTOSIS AND CHRONIC RHEUMATOID ARTHRITIS

P53，细胞凋亡与慢性类风湿性关节炎

• 批准号: 6100509
• 负责人: DOUGLAS R GREEN
• 金额: $ 11.42万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-03-01 至 2000-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6100509
• 关键词: apoptosis; cell growth regulation; cellular pathology; disease /disorder model; free radical oxygen; gene mutation; gene targeting; human tissue; immunocytochemistry; laboratory mouse; nitric oxide; oxidative stress; p53 gene /protein; rheumatoid arthritis; tumor suppressor genes

This is an application to test a novel hypothesis on the pathogenesis of rheumatoid arthritis. We propose to examine the possible role of p53 mutations in hyperplastic expansion of the synovium as a consequence of inflammation. Reactive oxygen species (ROS) and nitric oxide (NO), present in the inflamed joint, are known to be active inducers of apoptosis, which we propose normally offsets tissue expansion induced by growth factors at the site. Based on studies on precancerous skin lesions, we propose that mutations in p53 can occur as a consequence of long term exposure to the mutagenic action of ROS and NO, and further, that such mutations produce a state of resistance to apoptosis cause by ROS-and/or NO- induced DNA damage of synoviocytes. This resistance to apoptosis results in massive accumulation of cells despite modest proliferation of the tissue, and this expansion can occur in the fact of apoptosis of wild-type cells at the site. With time, the resulting pannus contributes to joint damage. Thus, while we consider rheumatoid arthritis a predominantly immunologic disease, we believe that nonimmunologic events (such as somatic defects in p53-mediated apoptotic response) can make a major contribution to the progression of the disease. We propose to test this model in three ways. First, we plan to examine the role of p53 in apoptosis inducted by ROS and NO in the relevant cell types (macrophages, fibroblast-like synovial cells) and related cells. This will be done in culture, through the use of temperature-sensitive p53 mutants that permit conditional p53 function in a variety of cells. Since p53 is required in many cells for the induction of apoptosis following DNA damaging agents, we expect that it will have such a role here as well. Concurrently, we will examine tissue from rheumatoid joints and controls for the presence of mutation in p53, both by immunohistochemistry and by molecular approaches. These methods have been developed for use in cancer research but have not yet been applied to inflammatory disease. Finally, we will assess the role of p53 in apoptosis and disease progression in mice lacking this gene through targetted disruption, in which we will induce joint inflammation by immunologic means. Together, these studies will form the basis for rigorous pursuit of this model or adjusted models. Although the proposed studies are high risk, they are fully feasible in a three year period, and if successful they will have important consequences for our understanding of rheumatoid arthritis.

这是一个应用来检验关于发病机制的新假说。 类风湿性关节炎。我们建议研究一下可能的作用 滑膜增生性扩张中的P53突变 炎症的后果。活性氧(ROS)和 一氧化氮(NO)存在于发炎的关节中，已知 细胞凋亡的活性诱导物，我们通常认为它可以抵消 局部由生长因子诱导的组织扩张。基于 关于癌前病变的研究，我们提出突变在 P53可能是长期暴露于 ROS和NO的诱变作用，而且这些突变 产生一种由ROS-和/或NO-引起的抵抗凋亡的状态 诱导滑膜细胞DNA损伤。这种对细胞凋亡的抵抗 导致细胞大量堆积，尽管细胞数量不多 而这种扩张可以发生在细胞凋亡的事实中 现场有野生型细胞。随着时间的推移，由此产生的血管疙瘩 会造成关节损伤。因此，当我们考虑类风湿时 关节炎是一种主要的免疫性疾病，我们认为 非免疫性事件(如P53介导的体细胞缺陷 细胞凋亡反应)可以对进展做出重大贡献 这种疾病的危害。我们建议通过三种方式来测试这个模型。第一, 我们计划研究P53在ROS诱导的细胞凋亡中的作用 相关细胞类型(巨噬细胞、成纤维细胞样细胞)中的NO 滑膜细胞)和相关细胞。这将在文化中完成， 通过使用对温度敏感的p53突变体 条件性P53在多种细胞中发挥作用。由于需要使用P53 在许多细胞中诱导DNA后的细胞凋亡 破坏代理人，我们预计它将在这里发挥这样的作用 井。同时，我们将检查类风湿关节的组织 和控制p53突变的存在，这两种方法都是通过 免疫组织化学和分子生物学方法。这些方法 已被开发用于癌症研究，但尚未被 适用于炎症性疾病。最后，我们将评估 P53基因缺失小鼠的细胞凋亡和疾病进展 通过有针对性的破坏，在这种情况下我们将引发联合 通过免疫学手段引起的炎症。总而言之，这些研究将 形成了严格追求这种模式或调整模式的基础。 虽然拟议的研究风险很高，但它们是完全可行的 在三年内，如果成功，他们将拥有重要的 对我们理解类风湿性关节炎的影响。