促炎相关因子MCP-1对高度近视白内障眼内微炎症的调控机制研究

Highly myopic cataract (HMC) is a type of complicated cataract with high risk of blindness, of which the therapeutic outcome is closely related to the intraocular micro-environment. However, relevant studies are scarce. Previously, we identified the micro-inflammation in HMC eyes manifesting as elevated levels of pro-inflammatory factor MCP-1 and growth factors including TGF-β2, HGF and PDGF-AA in aqueous humor along with up-regulated expression of adhesion molecule ICAM-1 in lens epithelial cells (LECs). Thereinto, MCP-1 is very likely to be a key mediator of micro-inflammation in HMC eyes. This project prepares to further verify the variations of previously identified cytokines in aqueous humor and ICAM-1 in LECs in HMC eyes at baseline with larger sample size and investigate their correlation with capsular contraction after cataract surgery. Co-culture system of macrophage and LECs will also be established to analyze the role of MCP-1 in regulation of micro-inflammation under stressed condition. Furthermore, extracapsular cataract extraction will be performed on MCP-1 knockout mice with lens-induced high myopia to investigate the changes of cytokine levels in aqueous humor, chemotaxis and function regulation of macrophage by MCP-1 and changes of biological properties of LECs under baseline and stressed conditions in vivo. From the population, cell and animal levels, the current project aims to unveil the mechanisms and effects of MCP-1 in regulating intraocular micro-inflammation of HMC under baseline and stressed conditions and to reveal its correlation with the therapeutic outcome.

高度近视白内障（HMC）是一种高致盲风险的复杂白内障，其治疗预后与眼内微环境密切相关，但机制研究匮乏。我们前期发现HMC眼内存在微炎症：其房水促炎相关因子MCP-1和生长因子TGF-β2/HGF/PDGF-AA水平升高，晶状体上皮细胞（LECs）炎性粘附分子ICAM-1表达上调，而其中MCP-1很可能是其微炎症的关键介导因子。本项目拟大样本验证基础状态HMC房水中前期发现的细胞因子浓度变化规律和LECs内ICAM-1表达，及其与术后囊袋收缩的关系；建立巨噬细胞和LECs共培养模型，分析应激状态MCP-1对微炎症的调控和效应；构建MCP-1基因敲除小鼠离焦高度近视模型并行晶状体囊外摘除术，分析基础和应激状态房水细胞因子变化、MCP-1对巨噬细胞的趋化和功能调控及对LECs的生物学效应。旨在从人群、细胞、动物层面明确MCP-1对基础和应激状态HMC眼内微炎症的调控机制和效应，揭示与预后的关系。

高度近视白内障（HMC）是一种高致盲风险的复杂白内障，其治疗预后与眼内微环境密切相关，但机制不明。我们前期发现HMC眼内存在微炎症：其房水促炎相关因子MCP-1水平升高，晶状体上皮细胞（LECs）炎性粘附分子ICAM-1表达上调，而其中MCP-1很可能是其微炎症的关键介导因子，为进一步明确MCP-1在HMC眼内微炎症中作用机制，我们开展本项目。首先，通过大样本人房水因子芯片验证了HMC房水MCP-1水平升高，并与促炎因子IL-1α/IL-8/TGF-β1/TGF-β2、LECs炎性粘附分子ICAM-1表达、囊袋收缩程度及眼压升高显著相关；进一步构建了MCP-1基因敲除小鼠离焦高度近视模型，证实了高度近视小鼠眼内MCP-1表达上调、外周血来源的单核巨噬细胞在葡萄膜组织浸润增加并向M1促炎表型分化、LECs TGF-β通路激活及α-SMA上调等变化，通过磁共振渗漏实验和连接蛋白occludin/ZO-1染色发现了高度近视血眼屏障的破坏，最终MCP-1基因敲除可抑制上述一系列改变，从而验证了MCP-1对眼内微炎症的调控及其对LECs的影响。通过本项目探索，我们提出MCP-1调控HMC眼内微炎症机制假说：HMC眼内为以 MCP-1 升高为重要特征的微炎症，MCP-1趋化外周血中的促炎单核细胞浸润到眼前节组织，并促进单核细胞活化为M1型促炎巨噬细胞，分泌促炎因子和生长因子，进而激活LECs TGF-β通路，发生上皮间质转分化，同时MCP-1还通过促进血眼屏障的破坏进一步加重炎症恶性循环，最终导致囊袋收缩。本项目阐明了MCP-1在HMC眼内微炎症的关键作用，为HMC微炎症相关并发症的预后预测和有效干预提供了新靶点。