Ability of Antibody Against Coxiella burnetii LPS to Confer Protective Immunity

本申请的目的是表征抗体（Ab）介导的免疫（AMI）的作用 抗贝氏柯克斯体感染。它是基于我们的观察：1）福尔马林灭活I期疫苗 （PI-V）对强毒C.在BALB/c小鼠中进行贝氏体攻击，但I期 疫苗（PII-V）没有提供显著的保护; 2）PI-V和PII-V引起不同的Ab应答，而 细胞因子反应相似; 3）I相脂多糖（PI-LPS）能够诱导细胞因子水平升高， 保护作用类似于PI-V，而II相脂多糖（PII-LPS）没有提供显著的保护作用; 4 从PI-V疫苗接种的小鼠被动转移免疫血清（IS）诱导了与PI-V相似的保护水平 在幼稚小鼠中接种。第一个具体目标是描述AMI对C.贝氏感染 工作假设是Ab在P1-V诱导的抗C.贝氏感染 我们将评估IS诱导的抗C.腹腔内感染贝氏体， 气溶胶激发的BALB/c小鼠和气溶胶激发的豚鼠。我们将确定是否Abs是 IS诱导保护的活性成分，并定义被动转移抗体的动力学 保护第二个具体目标将确定关键的保护性抗体同种型和表位靶标 工作假设是AMI的靶标是LPS核心和/或O-侧链多糖。我们会 从血清中提取免疫球蛋白，确定IS的保护性成分是否为抗体。我们会 然后确定保护性AMI的同种型，以发展AMI机制的假说。的 AMI识别的表位将使用高度纯化的LPS来定义，LPS组分通过 免疫和吸收实验。作为补充方法，一组抗贝氏隐球菌LPS 将产生单克隆抗体（Mab），并检测其通过被动免疫 转移这些研究将为设计亚单位疫苗提供可行性、概念验证研究， 我们计划将其作为产品开发提案提交，用于竞争继续申请， 的WRCE。

The objective of this application is to characterize the role of antibody (Ab)-mediated immunity (AMI against Coxiella burnetii infection. It is based on our observations: 1) formalin-inactivated phase I vaccine (PI-V) generated complete protection against virulent C. burnetii challenge in BALB/c mice, but phase I vaccine (PII-V) did not confer significant protection; 2) PI-V and PII-V elicited different Ab responses, while cytokine responses were similar; 3) phase I lipopolysaccharide (PI-LPS) was able to induce a level o protection similar to PI-V while phase II lipopolysaccharide (PII-LPS) conferred no significant protection; 4 passive transfer of immune serum (IS) from PI-V vaccinated mice induced a level of protection similar to PI-V vaccination in naive mice. The first specific aim is to characterize the role of AMI against C. burnetii infection The working hypothesis is that Abs play a critical role in Pl-V-induced protection against C. burnetii infection We will evaluate the contribution of IS-induced protection against C. burnetii infection in intraperitoneal and aerosol challenged BALB/c mice and aerosol challenged guinea pigs. We will determine whether Abs are the active components of IS-induced protection and define the kinetics of passively transferred antibody protection. The second specific aim will determine the key protective antibody isotypes and epitope targets The working hypothesis is that the target of AMI is LPS core and/or O-side chain polysaccharide. We wil ourify immunoglobulin from serum and establish whether the protective component of IS is antibody. We wil then determine the isotype of protective AMI to develop a hypothesis on the mechanism of AMI. The epitopes recognized by AMI will be defined using highly purified LPS, and LPS components through mmunizations and absorption experiments. As a complimentary approach, a panel of anti-C.burnetii LPS monoclonal antibodies (Mabs) will be generated and tested for the ability to confer immunity by passive transfer. These studies will provide the feasibility, proof of concept research to design a subunit vaccine, which we plan to submit as a product development proposal for the competing continuation application for the WRCE.