人免疫缺陷病毒致紧密连接相关基因表达和调控异常的分子基础

Epithelium is the barrier to keep the inner environment homeostasis, block the invasion of pathogens and their products. Tight junctions are the key component of the selective epithelial barrier. Mice deficient in tight junction (such as knockout of claudin-1) die within 24 hours of birth. Abnormal tight junctions have been associated with various diseases such as autoimmunity in humans. Expression and distribution of tight junction proteins in HIV infected humans and SIV infected macaques altered significantly, cause microbial translocation and systemic immune activation, and drive the rapid progression of AIDS. Clinical trials have shown that to heal gut mucosa is a promising application in AIDS treatment. However, very little studies have been done as to the effects and mechanisms of HIV-1 on the tight junction molecules of intestinal epithelial cells in their specific milieu. In this proposal, cellular and molecular methods including deep sequencing were be used to study the effects of HIV-1 gp120, alone or in combination with cytokines and PAMP molecules, on the structure, function and expression of related genes of tight junctions of intestinal epithelial cells; to clarify the changes and underlying mechanisms of the functional integrity of tight junctions in response to HIV infection. The purpose is to provide new knowledges on AIDS pathogenesis, new targets for AIDS therapy and new ideas for AIDS prevention.

上皮是维持机体内环境稳定、阻止病原体及其产物侵入机体的天然屏障。紧密连接是上皮选择性透过屏障的关键结构。紧密连接缺陷小鼠（如敲除claudin-1基因）在出生后24小时内死亡。人类紧密连接功能异常与自身免疫等多种疾病密切相关。HIV感染者和SIV感染恒河猴中紧密连接蛋白表达和分布显著改变，导致微生物移位、系统免疫活化和艾滋病快速进展。修复肠道粘膜的临床试验已在艾滋病的治疗中显示出了良好的应用前景。但目前对HIV-1影响处于特定微环境中的肠道上皮细胞紧密连接的表达和调控的机制研究甚少。本项目拟利用深度测序等现代细胞分子生物学技术研究HIV-1 gp120单独和与细胞因子和病原相关分子模式分子联合使用对肠上皮紧密连接结构、功能、及相关基因表达的影响，探索紧密连接功能完整性在艾滋病病毒感染后的变化和变化机制。为认识艾滋病的病理机制提供新知识、为治疗艾滋病提供新的干预靶点，为预防艾滋病提供新思路。

上皮是维持机体内环境稳定、阻止病原体及其产物侵入机体的天然屏障。紧密连接是上皮选择性透过屏障的关键结构。紧密连接缺陷小鼠（如敲除claudin-1基因）在出生后24小时内死亡。人类紧密连接功能异常与自身免疫等多种疾病密切相关。HIV感染者和SIV感染恒河猴中紧密连接蛋白表达和分布显著改变，导致微生物移位、系统免疫活化和艾滋病快速进展。修复肠道粘膜的临床试验已在艾滋病的治疗中显示出了良好的应用前景。但目前对HIV-1影响处于特定微环境中的肠道上皮细胞紧密连接的表达和调控的机制研究甚少。本项目研究了HIV-1 gp120单独和与细胞因子和病原相关分子模式分子联合使用对肠上皮紧密连接结构、功能、及相关基因表达的影响。发现免疫缺陷病毒可以影响比已知更多的紧密连接相关基因的表达，表明HIV-1对紧密连接的影响远比之前认为的要要复杂；发现IL-17A和IL-17F都有可能参与了HIV-1所致粘膜损伤的病理过程，而它们的受体及下游信号通路复杂；发现IL-17A和IL-17F在体外能阻止HIV-1所致上皮屏障损伤，提示有可能靶向IL-17通路干预HIV-1相关粘膜损伤。另外，为更好利用恒河猴开展相关研究，我们克隆鉴定了恒河猴IL-17A、IL-17F和IL-22基因。本研究扩展了人们对艾滋病的病理机制的认识、为治疗艾滋病提供了新的干预靶点，为预防艾滋病提供了新思路。