PROTECTIVE ANTIGENS OF SCHISTOSOMA MANSONI

曼氏血吸虫的保护性抗原

• 批准号: 3790945
• 负责人: ADEL A F MAHMOUD
• 金额: --
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3790945
• 关键词: B lymphocyte; Salmonella typhimurium; Schistosoma mansoni; active immunization; affinity chromatography; cellular immunity; clone cells; complementary DNA; disease /disorder model; epitope mapping; genetic library; genetic manipulation; helminthic antigen; high performance liquid chromatography; host organism interaction; humoral immunity; immunity; immunological substance; immunoregulation; laboratory mouse; molecular cloning; monoclonal antibody; schistosomiasis; tropical medicine; vaccines

The overall objective of this proposal is to use the current understanding of host defenses against schistosomiasis and of the biochemistry and molecular biology of the causative organisms to develop immunologic alternatives to control. Such an effort is needed because of the global prevalence of infection and the burden of illness in human population infected with several species of schistosomes. In spite of the recently developed anti-schistosome drugs, their long term effect and the danger of drug resistance may become a limiting factor in their usefulness as control measures. The target organism is a formidable immunologic challenge but recent evidence from our laboratory and others indicate that monoclonal antibodies and purified parasite antigens are capable of inducing significant resistance in experimental animals. Furthermore, the expanding science and technology of vaccine development and delivery offer new unique opportunities. We therefore propose to use the knowledge of host protective responses, its mechanisms and the increasingly expanding molecular understanding of schistosomes in order to isolate and characterize parasite antigens that can be tested as candidate vaccines. The specific aims of this proposal are: 1. Biochemical characterization and cloning of protective antigens. 2. Selection of candidate subunit peptides for vaccines development. 3. Determination of optimal vaccination strategies. 4. Evaluation of human response to candidate vaccines. The proposal is designed as a series of step by step studies by using first immunoaffinity and biochemical procedures to purify two candidate antigens (SmW68 and SmW43) that have been identified by protective monoclonal antibodies. This will be followed by HPLC repurification using reverse phase hydrophobic interaction or ion exchange columns. Components peptides for amino acid sequence analysis will be generated from deglycosylate antigens by limited tryptic digestion. The larger peptides with single N- terminal will then be sequenced. Isolation of corresponding cDNAs from expression libraries will be achieved either by immunologic screening or by using oligonucleotide probes. Once defined peptide sequence are identified, we will use a combination of immunologic and biochemical procedures to delineate immunogenic epitopes and their effectiveness in inducing resistance in mice to be challenged percutaneously with S. mansoni. A major goal is to test these candidate vaccines for lack of sensitization to the immunopathological sequelae of schistosomiasis. Optimal vaccination strategies with stimulation of specific components of the host immune response or with clinically acceptable adjuvants will be determined. In addition, sera and peripheral mononuclear cells from individuals infected with S. mansoni will be examined for antibodies and sensitized T cells to candidate vaccine individuals infected with S. mansoni will be examined for antibodies and sensitized T cells to candidate vaccine antigens. We will also examine the in vivo human response to vaccination using the SCID-hu mouse model. Results obtained from these studies should pave the way to defining candidates for anti-schistosome vaccine.

该提案的总体目的是利用当前的理解 针对血吸虫病和生物化学的宿主防御措施 病因生物的分子生物学发展免疫学 控制的替代方案。 需要这样的努力，因为全球 感染的患病率和人口中的疾病负担 感染了几种血吸虫。 尽管最近 开发了抗速剂药物，其长期作用和危险 耐药性可能会成为其对控制的有用性的限制因素 措施。 目标生物是一个巨大的免疫学挑战，但 我们实验室和其他实验室的最新证据表明单克隆 抗体和纯化的寄生虫抗原能够诱导 实验动物的显着抗药性。 此外，扩展 疫苗开发和交付的科学技术提供了新的独特 机会。 因此，我们建议使用主机的知识 保护性响应，其机制以及日益扩展的 分子对血块的理解，以分离和分离 表征可以作为候选疫苗测试的寄生虫抗原。 该提案的具体目的是： 1。保护性的生化表征和克隆 抗原。 2。选择疫苗的候选亚基肽 发展。 3。确定最佳疫苗接种策略。 4。评估人类对候选疫苗的反应。 该提案被设计为一系列逐步研究 免疫亲和力和生化程序，以净化两种候选抗原 （SMW68和SMW43）已通过保护性单克隆识别 抗体。 随后将使用反向进行HPLC重新验证 相疏水相互作用或离子交换柱。 成分肽 对于氨基酸序列分析，将从脱糖基酸酯中产生 抗原有限的胰蛋白酶消化。 具有单个N-的较大肽 然后将对终端进行测序。 从中分离出相应的cDNA 表达式库将通过免疫学筛查或通过 使用寡核苷酸探针。 一旦定义的肽序列是 确定，我们将使用免疫学和生化的组合 描述免疫原性表位的程序及其在 诱导小鼠的抗性被S。 曼森。 一个主要目标是测试这些候选疫苗的缺乏 对血吸虫病的免疫病理后遗症的敏感性。 最佳疫苗接种策略，并刺激特定组件 宿主免疫反应或临床上可接受的佐剂将是 决定。 另外，来自的血清和周围单核细胞 感染了曼氏链球菌的个体将接受抗体的检查和 将T细胞敏感到感染S的候选疫苗个体。 将检查Mansoni的抗体和对候选的T细胞敏感的T细胞 疫苗抗原。 我们还将检查体内人类对 使用SCID-HU小鼠模型的疫苗接种。 从这些结果获得的结果 研究应该为定义抗速剂的候选人铺平道路 疫苗。