Construction of safe and effective live tuberculosis vaccines

安全有效的结核活疫苗的构建

• 批准号: 8230473
• 负责人: Steven A Porcelli
• 金额: $ 41.5万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8230473
• 关键词: Address; Adjuvant; Animals; Antigen Presentation; Antigens; Apoptosis; Apoptotic; Attenuated; Attenuated Vaccines; Bacillus (bacterium); Bacteriophages; CD4 Positive T Lymphocytes; CD8B1 gene; Cells; Chemicals; Communicable Diseases; Cosmids; Disease; Gene Deletion; Gene Mutation; Genes; Genetic; Goals; Growth; Histocompatibility Antigens Class I; Histocompatibility Antigens Class II; Human; Immune; Immune response; Immunity; Immunologic Deficiency Syndromes; Immunology; In Vitro; Laboratories; Lead; Life; Link; MHC Class II Genes; Mediating; Metabolic; Methodology; Multi-Drug Resistance; Mus; Mutagenesis; Mutation; Mycobacterium smegmatis; Mycobacterium tuberculosis; Phagocytes; Population; Post-Translational Protein Processing; Prevention; Production; Protein Subunits; Proteins; Research Personnel; Rodent; Screening procedure; Specificity; System; T cell response; T memory cell; T-Lymphocyte; T-Lymphocyte Epitopes; T-Lymphocyte Subsets; TNF gene; Testing; Tuberculosis; Tuberculosis Vaccines; Vaccination; Vaccines; Virulence; Work; auxotrophy; cytokine; design and construction; human disease; immunogenic; immunogenicity; improved; in vivo; interest; mortality; mouse model; mutant; mycobacterial; novel; overexpression; pathogen; pre-clinical; prevent; public health relevance; resistant strain; response; vaccine candidate; vaccine development

DESCRIPTION (provided by applicant): This proposal seeks to understand in greater detail the mechanisms by which Mycobacterium tuberculosis blocks the priming of effective host immunity, with the ultimate goal of using this information to create more effective live vaccine strains. Previous work identified multiple mycobacterial genes involved in blocking apoptosis of infected host cells, which is intimately linked to the ability of the pathogen to prevent presentation of its antigens by MHC class I. Extensive preliminary work has also identified genes in M. tuberculosis that interfere with MHC class II antigen presentation, and genes that block production of key cytokines. A major goal of this proposal is to construct safely attenuated strains of M. tuberculosis in which specific immune evasion genes have been deleted, thus creating more effective vaccines for priming of anti- mycobacterial immunity. The approach involves identifying the most potent anti- apoptotic genes from a group of four candidates that have already been partially characterized, and combining mutations in these with strongly attenuating auxotrophy mutations to eliminate virulence. Precise mutations in the genes of interest will be created using allelic exchange mediated by specialized transducing phages, a methodology that is well established in the laboratory of the PI and his collaborators. The potency of candidate vaccine strains will be further enhanced by incorporating additional mutations in genes that interfere with MHC class II presentation, or with production of IL-12p70 or TNF. Immunological studies of CD4 and CD8 T cell priming by candidate vaccine strains will be carried out in mouse models, allowing identification of the most favorable combinations of specific gene deletions to advance into preclinical vaccination studies in rodents. Studies of the induction of stable T cell memory by candidate vaccine strains will be performed in mice, and the impact of boosting primary responses with mycobacterial proteins will also be initiated. Overall, the proposed studies will significantly advance our understanding of the host-pathogen interaction in tuberculosis, and contribute directly to vaccine development for prevention and control of this major human disease. PUBLIC HEALTH RELEVANCE: This proposal aims to understand in greater detail the mechanisms by which Mycobacterium tuberculosis evades host immunity to cause serious disease and mortality. The information gained will be applied to the design and construction of better vaccines for the prevention of tuberculosis.

描述（由申请人提供）：该提案旨在更详细地了解结核分枝杆菌阻止有效宿主免疫启动的机制，最终目标是利用这些信息来创建更有效的活疫苗株。先前的工作鉴定了多种分枝杆菌基因参与阻断受感染宿主细胞的凋亡，这与病原体阻止 MHC I 类呈递其抗原的能力密切相关。大量的初步工作还鉴定了结核分枝杆菌中干扰细胞凋亡的基因。 MHC II 类抗原呈递，以及阻止关键细胞因子产生的基因。该提案的一个主要目标是构建安全减毒的结核分枝杆菌菌株，其中特定的免疫逃避基因已被删除，从而创造出更有效的疫苗来启动抗分枝杆菌免疫。该方法包括从已部分表征的四个候选基因中鉴定出最有效的抗凋亡基因，并将这些基因中的突变与强烈减弱的营养缺陷型突变相结合以消除毒力。感兴趣的基因中的精确突变将通过专门的转导噬菌体介导的等位基因交换来产生，这是 PI 及其合作者实验室中成熟的方法。通过在干扰 MHC II 类呈递或 IL-12p70 或 TNF 产生的基因中加入额外的突变，候选疫苗株的效力将得到进一步增强。候选疫苗株引发的 CD4 和 CD8 T 细胞免疫学研究将在小鼠模型中进行，从而确定特定基因缺失的最有利组合，从而进入啮齿类动物的临床前疫苗接种研究。候选疫苗株诱导稳定 T 细胞记忆的研究将在小鼠中进行，并且还将启动分枝杆菌蛋白增强初次反应的影响。总体而言，拟议的研究将显着增进我们对结核病宿主与病原体相互作用的理解，并直接有助于开发预防和控制这种主要人类疾病的疫苗。 公共卫生相关性：该提案旨在更详细地了解结核分枝杆菌逃避宿主免疫力导致严重疾病和死亡的机制。获得的信息将应用于设计和构建更好的预防结核病的疫苗。