肠道微生态失衡在慢性重症乙肝与慢加急性肝衰竭（ACLF）发生发展中起到初始激发、继发加重作用，对临床肝衰竭的防治带来了新的挑战。因此，研究肠道微生态失衡分子机理将有助于减少慢性携带者急性发作及重症化的发生率和死亡率。本项目拟利用高通量多维液相-高分辨串联质谱平台，结合基于宏基因组与非基于宏基因组的信息学手段，开发适用于研究复杂微生态样品的鸟枪法宏蛋白组学策略。本项目将利用该宏蛋白组学研究对比正常、慢性乙肝和慢加急性肝衰竭中肠道菌群蛋白表达谱，阐明肠道菌群在慢肝与慢加急性肝炎病理条件下结构失衡的动力学过程。结合临床数据，筛选参与肠道菌群失衡过程的关键蛋白与通路；结合代谢组数据，研究宏蛋白表达谱变化对整体代谢网络结构和功能的影响，筛选与代谢变化相关的蛋白（酶）；筛选能反映慢性或慢加急性肝衰竭中微生态失衡的蛋白或代谢物类预警或预后标志物，为慢性乙肝和慢加急性肝衰竭的防治提供新思路和新策略。

Microbiota dysbiosis has been suggested to play vital roles during HBV-induced acute-on-chronic liver failure (ACLF) pathogenesis and progression, which create new challenges for the prevention and clinical treatment of ACLF. Therefore, understanding the molecular mechanism of intestinal microbiota dysbiosis might help to reduce the incidence and mortality of ACLF in population with chronic HBV infection. This project first aims to develop a shotgun-based metaproteomics method to analyze complex microbiota proteome, by combining the high-throughput MDLC-HRMS/MS platform with both metagenomics-dependent and -independent bioinformatics workflows. This metaproteomic method will then be used to characterize and compare gut microbiota metaproteome expression profiles from normal, chronic HBV and ACLF patients, to describe the dynamics of structure dysbriosis of gut microbiota during chronic HBV and ACLF. Clinical data will be cross-referred to select key proteins and pathways participated the microbiota dysbriosis; metabolomics data will be linked to investigate the impact of metaproteome expression changes on the metabolism network and functions, and to select key proteins (enzymes) related to metabolic changes. Diagnostic and prognostic protein or metabolite markers that reflecting microbiota dysbriosis process during chronic HBV and ACLF will be screened to provide foundations to develop novel prevention and treatment strategies.