TLR4在肝硬化肠道菌群漂变诱导的肠道屏障功能障碍和肝硬化重症化中的免疫机制研究

肝硬化重症化以及进展至慢加急性肝衰竭是目前导致患者死亡的重要因素，具体发病机制仍未完全阐明，目前的研究发现肝硬化患者肠道微生态存在严重失衡，来自肠道的细菌激活TLR4，引发肠道炎症，诱导肝脏炎症，促进疾病进展，但具体免疫机制不清，在先前的研究中，我们进行的肝硬化相关的肠道菌群的宏基因组学研究已经明确了肝硬化患者的肠道菌群结构特点，即拟杆菌丰度显著降低，韦荣氏球菌丰度显著升高，在本项目中，拟分别从人体标本（粪便和外周血）、动物模型两个方面，运用（16srDNA测序、流式细胞技术、Western Blot、荧光定量PCR、免疫组化实验）等多种方法，通过检测患者肠道菌群与TLR4之间存在相关性以及在动物模型中明确肠道菌群对TLR4信号通路下游中靶蛋白的影响，阐明肠道菌群与TLR4相关通路中靶基因的相互作用，以及在肠道屏障功能和肝脏炎症病变的发生中起关键作用，为发现新的临床干预靶标奠定基础。

Severe cirrhosis and the progression to acute on chronic liver failure are important factors leading to the death of patients. The specific pathogenesis has not been fully elucidated. The current study found that the intestinal microecology of patients with cirrhosis has a serious imbalance, and bacterial activation from the gut TLR4, which triggers intestinal inflammation, induces liver inflammation, and promotes disease progression, but the specific immune mechanism is unclear. In previous studies, we conducted a metagenomics study of the cirrhosis-related intestinal flora that has identified patients with cirrhosis The structural characteristics of the intestinal flora, that is, the abundance of Bacteroides is significantly reduced, and the abundance of Veillonella is significantly increased. In this project, it is intended to apply from two aspects of human specimens (feces and peripheral blood) and animal models. (16srDNA sequencing, flow cytometry, Western Blot, fluorescent quantitative PCR, immunohistochemistry) and other methods, by detecting the correlation between the patient's intestinal flora and TLR4 and determining the intestinal flora in animal models Effects on target proteins downstream of the TLR4 signaling pathway, elucidates the interaction of the gut flora with target genes in the TLR4-related pathway, and The occurrence of barrier function and inflammatory lesions of the liver plays a key role in laying the foundation for the discovery of new targets for clinical intervention.