RETINAL DEGENERATION IN UVEITIS

葡萄膜炎引起的光感受器细胞变性是主要的 在美国和其他国家导致失明。上一首 实验研究揭示了炎症的重要性 吞噬细胞在光感受器细胞变性启动中的作用 葡萄膜炎。这种退化似乎是由吞噬细胞的 活性氧物种的释放，如超氧化物，在 发炎。然而，我们的初步实验表明，在 葡萄膜炎，一氧化氮衍生的过氧亚硝酸根，形成于 光感受器细胞周围存在超氧化物，可能是 在光感受器细胞退化的启动过程中是必不可少的。 此外，我们对葡萄膜炎的初步研究结果表明， 一氧化氮生成酶一氧化氮合酶主要在 巨噬细胞渗入视网膜外，而不是巨噬细胞 渗入葡萄膜、角膜缘组织或结膜。此外， 视黄醇蛋白(S抗原)可诱导巨噬细胞产生一氧化氮合酶。 基于这些新的发现，我们假设，在葡萄膜炎视网膜 外周血中一氧化氮合酶选择性表达启动退变 视网膜巨噬细胞的浸润和这种一氧化氮合酶的表达被诱导 视网膜中的可溶性蛋白质。我们将使用 具体目标如下：1.测定激活后一氧化氮合酶的诱导 巨噬细胞由S抗原。2.确定细胞信号转导机制 S抗原诱导巨噬细胞一氧化氮合酶的作用。3.检测角色 一氧化氮合酶产物在光感受器细胞变性启动中的作用 葡萄膜炎。 已经组建了一个专家小组来承担这一项目。 Vijay Kalra教授是剖析信号通路和 蛋白质化学。亚历克斯·塞瓦尼安教授是免费方面的权威 自由基生物学与脂质过氧化。导演特里·D·李博士 位于加利福尼亚州杜阿尔特市希望城的核心蛋白质测序实验室， 是GC/MS和蛋白质测序方面的专家。这支专家团队有 在葡萄膜炎和其他相关领域与P.I.合作 眼内发炎。首席调查员经验丰富 在实验性葡萄膜炎、自由基生物学和GC/MS领域。 这项研究的结果将阐明导致 与葡萄膜炎的视网膜变性有关，并可能提供一种新的 视网膜退行性变的预防治疗途径 葡萄膜炎及相关病症。 本提案中使用的缩写：GC/MS=气相色谱-质量 色谱学；LC/MS=液-质联用；UV- 高效液相色谱=紫外-高压液相色谱仪。

The photoreceptor cell degeneration resulting from uveitis is a major cause of blindness in the United States and other nations. Previous experimental studies have revealed the importance of inflammatory phagocytes in the initiation of photoreceptor cell degeneration in uveitis. This degeneration appears to be mediated by the phagocyte's release of reactive oxygen species, such as superoxide, at the site of inflammation. However, our preliminary experiments show that in uveitis, the nitric oxide-derived radical peroxynitrite, formed in the presence of superoxide, around the photoreceptor cells could be essential in the initiation of photoreceptor cell degeneration. Moreover, the preliminary results of our studies on uveitis reveal that the nitric oxide-generating enzyme NOS is expressed mainly in the macrophages infiltrating the outer retina rather than in the macrophages infiltrating the uvea, limbal tissue or conjunctiva. Furthermore, the retinal protein arrestin (S-antigen) could induce NOS in macrophages. Based on such novel findings we hypothesize that, in uveitis retinal degeneration is initiated by NOS selective expression in the outer retinal macrophage infiltration and that such NOS expression is induced by retinal soluble proteins. We will test our hypothesis with the following specific aims: 1. Determine the induction of NOS in activated macrophages by S-antigen. 2. Determine the cellular signaling mechanism by which the S-antigen induces NOS in macrophages. 3. Detect the role of NOS products in the initiation of photoreceptor cell degeneration in uveitis. A team of experts has been assembled to undertake this project. Professor Vijay Kalra is an expert in dissecting signaling pathway and protein chemistry. Professor Alex Sevanian is an authority on free radical biology and lipid peroxidation. Dr. Terry D. Lee the director of the core protein sequencing laboratory at City of Hope, Duarte, CA, is an expert on GC/MS and protein sequencing. This team of experts has collaborated with the P.I. in the field of uveitis and other related intraocular inflammations. The principal investigator is experienced in the field of experimental uveitis, free radical biology and GC/MS. The results of this study would elucidate the initial events that lead to retinal degeneration in uveitis and could potentially provide a new therapeutic approach for the prevenation of retinal degenerations in uveitis and related conditions. Abbreviations used in this proposal: GC/MS =gas chromatography-mass spectrometry; LC/MS =liquid chromatrography-mass spectrometry; UV- HPLC=ultraviolet-high pressure liquid chromatrography.