VIRULENCE AND IMMUNITY TO MUCOID P. AERUGINOSA

对粘液铜绿假单胞菌的毒力和免疫力

• 批准号: 6626408
• 负责人: Gerald B Pier
• 金额: $ 40.9万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6626408
• 关键词: Pseudomonas aeruginosa; acetylation; active immunization; bacterial polysaccharides; bacterial vaccines; clinical research; cystic fibrosis; disease /disorder model; genetically modified animals; human subject; laboratory mouse; laboratory rabbit; microorganism immunology; opportunistic infections; passive immunization; vaccine development; virulence

DESCRIPTION: (Adapted from applicant's abstract): The major goals of this project are to understand basic aspects of virulence and host immunity to mucoid strains of P. aeruginosa that are major causes of morbidity and mortality in cystic fibrosis (CF) patients. About 2500 new babies with CF are born each year worldwide, and by adolescence 80 per cent of them will become chronically infected with mucoid P. aeruginosa. Clinical data clearly show that the decline in pulmonary function and ultimate early morality that occurs in P. aeruginosa-infected CF patients is due to mucoid P. aeruginosa infection and not to any other pathogen, including non-mucoid P. aeruginosa. Therefore, preventing new infections or treating established infections with immunotherapeutic agents that target mucoid P. aeruginosa should have a major impact on the health of CF patients. The primary hypotheses to be evaluated are that chronic mucoid P. aeruginosa infection is dependent on elaboration of an acetylated version of the mucoid exopolysaccharide (MEP) surface antigen, and that antibodies to the acetylated epitopes on MEP confer protection from chronic infection. A key component of this work will use our ability to initiate and establish a chronic mucoid P. aeruginosa infection in transgenic CF mice, a tool that, to date has eluded other researchers using these mice. The first hypothesis will be evaluated using in vitro studies to ascertain the ability of the acetylated MEP to confer resistance on mucoid P. aeruginosa to opsonic killing as well as in in vivo studies in CF mice. In the mice we will evaluate the ability of strains with differing abilities to acetylate MEP to establish and maintain a chronic colonization. The second hypothesis will be evaluated by production of conjugate vaccines composed of MEP with differing levels of acetylation, prepared by chemical manipulations. The conjugate vaccines will be evaluated for their immunogenicity in mice and rabbits and for their in vitro characteristics in regard to their ability to elicit antibodies that mediate opsonic killing of a multitude of mucoid P. aeruginosa strains. Next the vaccine(s) with the best ability to elicit high titers of broadly-reactive opsonic antibody will be tested in transgenic CF mice, using both active vaccination to prevent9 infection and passive therapy of established infection. In addition, we will test our proposed hypothesis that the presence of pre-existing, non-opsonic antibodies to non-acetylated epitopes on MEP in CF patients prior to the onset of mucoid P. aeruginosa infection interferes with the ability to mount a protective, opsonic response to the acetylated epitopes. Finally, we will evaluate the potential of some recently prepared human monoclonal antibodies to MEP to reduce the levels of mucoid P. aeruginosa in the lungs of infected CF mice. The results of this work should further our insights into the pathogenesis of mucoid P. aeruginosa infection, and promote development of effective vaccines and passive therapeutic reagents to prevent and treat mucoid P. aeruginosa infections in CF patients.

描述：（改编自申请人的摘要）： 项目将了解毒力的基本方面，并宿主免疫 铜绿假单胞菌的粘液菌株是发病率和 囊性纤维化（CF）患者的死亡率。大约有2500个带有CF的新婴儿 全世界每年出生，到青春期，其中80％将成为 长期感染了粘液藻P.铜绿。临床数据清楚地表明 肺功能的下降和最终的早期道德发生在P中。 铜绿菌感染的CF患者是由于粘液孢子虫感染和 没有任何其他病原体，包括非核酸芽孢杆菌。所以， 防止新的感染或治疗已建立的感染 靶向粘液p。Aeruginosa的免疫治疗剂应具有主要 对CF患者健康的影响。要评估的主要假设是 慢性粘液铜绿假单胞菌感染取决于阐述 粘液外多糖（MEP）表面抗原的乙酰化版本和 MEP赋予保护保护的乙酰化表位的抗体 慢性感染。这项工作的关键组成部分将利用我们的能力 在转基因中启动并建立慢性粘液P.铜绿假单胞菌感染 CF小鼠是迄今为止使用这些小鼠的其他研究人员的工具。 第一个假设将使用体外研究评估，以确定 乙酰化MEP赋予粘液P.铜绿假单胞菌抗性的能力 Opsonic杀戮以及CF小鼠的体内研究。在老鼠中，我们会 评估具有不同能力乙酰酸MEP的菌株的能力 建立并保持慢性定殖。第二个假设将是 通过生产由MEP组成的共轭疫苗评估 通过化学操作制备的乙酰化水平。共轭 将评估疫苗在小鼠和兔子中的免疫原性以及 他们的体外特征在其引起抗体的能力方面 这种介导了多种粘液藻菌菌株的opsonic杀死。 接下来，疫苗具有最佳的能力 将在转基因CF小鼠中测试广泛反应性的Opsonic抗体，并使用 可以预防9种感染的主动疫苗接种和被动治疗 已建立的感染。此外，我们将测试我们提出的假设 存在于非乙酰化表位的未存在的非上异位抗体的存在 在粘液P.铜绿假单胞菌感染发作之前，CF患者的MEP在MEP上 干扰能够安装保护性的能力，Opsonic对 乙酰化表位。最后，我们将评估一些最近的潜力 制备了与MEP的人类单克隆抗体，以降低粘液状态。 感染CF小鼠的肺中的铜绿。这项工作的结果应该 进一步，我们对粘液铜绿假单胞菌感染的发病机理的见解， 并促进有效疫苗和被动治疗试剂的开发 为了预防和治疗CF患者中的粘液藻感染。