BACTERIAL SURFACE PROTEINS: POTENTIAL TARGETS FOR SEPSIS

释放到血液中的细菌细胞壁成分被认为是引起引起革兰氏阴性败血症的炎症反应的重要因素。细菌外膜含有脂多糖（LPS）、外膜蛋白（OMPs）和磷脂。LPS作为脓毒症的重要介质已被广泛研究；omp在脓毒症中的重要性尚未得到系统评估。我们的初步数据表明，含有三种保守的omp和LPS的复合物可以从细菌释放到人血清中，也可以释放到脓毒症大鼠的循环中。我们已经鉴定了这三种蛋白质，并发现其中至少一种蛋白质具有生物活性。该项目的主要目标是进一步表征三种omp在脓毒症中的释放，评估它们在脓毒症发病机制中的作用，并评估抗omp免疫作为治疗脓毒症的一种手段。第一个具体目的是评估革兰氏阴性脓毒症患者和两种实验性革兰氏阴性脓毒症大鼠模型中OMP和OMP/LPS复合物的释放。第二个具体目标是评估单个OMP、OMP/LPS复合物和完整细菌表面的OMP在体外对分离免疫细胞的生物活性，以及通过研究LPS抗性和LPS应答小鼠的致死率、血液和器官中细胞因子的诱导以及肺中性粒细胞的隔离来评估完整细菌表面的OMP在体外对分离免疫细胞的生物活性。第三个具体目的是评价主动免疫对含OMP制剂在小鼠和大鼠脓毒症感染模型中的毒性的保护作用。申请人的长期职业目标是成为一名独立的研究者，研究革兰氏阴性感染和败血症的基本机制。职业发展计划旨在通过实践研究和教育活动扩展候选人的研究知识基础。这些将包括课程作业（实验室和教学），出席和参与实验室会议和研究研讨会，以及与咨询委员会成员的正式和非正式互动。候选人的最终目标是应用败血症机制的基本知识来开发针对细菌毒素的抗败血症策略。

Bacterial cell wall components released into the bloodstream are believed to be important in eliciting the inflammatory response that causes Gram-negative Sepsis. The bacterial outer membrane contains lipopolysaccharide (LPS), outer membrane proteins (OMPs), and phospholipids. LPS has been studied extensively as an important mediator in sepsis; the importance of OMPs in sepsis has not been systematically evaluated. Our preliminary data indicate that complexes containing three conserved OMPs and LPS are released from bacteria into human serum and are also released into the circulation of septic rats. We have identified the three proteins and have found that at least one of the proteins has biological activity. The major goals of this project are to further characterize release of the three OMPs in sepsis, to assess their roles in the pathogenesis of sepsis, and to evaluate anti-OMP immunity as a means of treating sepsis. The first specific aim is to assess release of OMPs and OMP/LPS complexes in humans with Gram- negative sepsis and in two models of experimental Gram-negative sepsis in rats. The second specific aim is to evaluate individual OMPs, OMP/LPS complexes, and OMPs on the surface of intact bacteria for biological activity in vitro on isolated immune cells, an in vivo by studying lethality, induction of cytokines in blood and organs, and pulmonary neutrophil sequestration in LPS resistant and LPS responsive mice. The third specific aim is to evaluate protective effects of active immunity on toxicity of OMP containing preparations in mice and in the rat infection models of sepsis. The applicant's long-term career objective is to become an independent investigator studying basic mechanisms of Gram- negative infection and sepsis. The career development plan is designed to expand the candidate's research knowledge base through hands-on research and educational activities. These will include course work (laboratory and didactic), attendance at and participation in laboratory meetings and research seminars, and formal and informal interactions with the Advisory Committee members. The ultimate goal of the candidate is to apply the fundamental knowledge of mechanisms involved in sepsis to develop anti-sepsis strategies that target bacterial toxins.