B.melitensis 1型致脑损害毒力基因筛选及其分子机制

Ningxia Province locates in Northwest of china As a farming-pastoral region,where settled a lot of hui Ethnic people.Brucellosis Epidemic in most areas and with a upward morbidity in some areas of Ningxia.Patients concurrenting or starting with meningitis appear constantly.Neurobrucellosis is recurrent,with longer duration,often misdiagnosed and difficult to cure, and disability.It is an urgent need to reveal the mechanisms of brain injury and to explore effective prevention measures.The whole-genome sequencing technology has an unique advantage in the study of bacterial virulence and pathogenesis. This project intends to take the Solexa sequencing technology to the B.melitensis type 1 strains that previously separated from cerebrospinal fluid of meningitis patients and isolated from peripheral blood of brucellosis patients,annotating the differentially expressed genes and predicting the virulence gene,screening virulence genes G1, G2, G3, ...of brain damage.Then the BALB/c mice model and human microglia cells model were used to authenticate the biological functions of virulence genes G1, G2, G3, ....through the virulence gene deletion strains which were established by the gene recombination.It is observed that the changes of HMGB1 and its receptor,and their corresponding inflammatory factor,cell polarity,cell's phagocytic function and activation level when the virulence gene absenced.This study will reveal the key regulatory proteins in the signal transduction pathway and will lay the foundation for finding new drug targets and for future vaccine development.

宁夏处于西北回族聚集的半农半牧区，是布氏杆菌病的多发地域，并在一些局部地区呈上升趋势，并发或以脑膜炎为首发的患者不断出现。病程长，反复发作，易误诊，难以治愈，严重可致残。因此揭示其脑损害机制，探讨有效防治措施，是急需解决的重要问题。本课题借助全基因组测序在研究细菌毒力、发病机制中的优势，拟采用Solexa测序技术对前期从急性脑膜炎患者脑脊液分离获得B.melitensis1型菌株与从布氏杆菌病患者外周血液分离同型菌株进行全基因组测序，差异基因注释和毒力基因预测，筛选导致脑损害可能的"毒力基因G1、G2、G3…"；应用基因重组方法分别构建"毒力基因"缺失株，并通过小鼠模型和人小胶质细胞模型进行生物学功能验证。观察"毒力基因"对HMGB1及其受体和相应的细胞炎性因子的变化，探讨细胞极性变化、吞噬功能和活化水平，揭示信号转导通路中的关键调控分子，为寻找新的药物作用靶点及疫苗研制奠定基础。

宁夏处于西北回族聚集的半农半牧区，是布氏杆菌病的多发地域，并在一些局部地区呈上升趋势，并发或以脑膜炎为首发的患者不断出现。病程长，反复发作，易误诊，难以治愈，严重可致残。因此揭示其脑损害机制，探讨有效防治措施，是急需解决的重要问题。本课题借助全基因组测序在研究细菌毒力、发病机制中的优势，拟采用全基因组测序技术对前期从急性脑膜炎患者脑脊液分离获得 B.melitensis1 型菌株与从布氏杆菌病患者外周血液分离同型菌株进行全基因组测序，差异基因注释和毒力基因预测，筛选导致脑损害可能的"毒力基因 G1、G2、G3…"；应用基因重组方法分别构建"毒力基因"缺失株，并通过小鼠模型和人小胶质细胞模型进行生物学功能验证。观察"毒力基因"对 HMGB1 及其受体和相应的细胞炎性因子的变化，探讨细胞极性变化、吞噬功能和活化水平，揭示信号转导通路中的关键调控分子，为寻找新的药物作用靶点及疫苗研制奠定基础。