Criteria-Directed Vaccine Generation Via Ag Mimicry, Adjuvancy, And APC-Targeting

通过 Ag 拟态、佐剂和 APC 靶向生成标准疫苗

• 批准号: 8443445
• 负责人: Edmund J Gosselin
• 金额: $ 58.4万
• 依托单位: ALBANY MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-09 至 2018-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8443445
• 关键词: Adjuvant; Adjuvanticity; Adverse effects; Aerosols; Agonist; Antigen Mimicry; Antigen Presentation Pathway; Antigen Targeting; Antigen-Presenting Cells; Antigens; B-Lymphocytes; Bacteria; Brain; C57BL/6 Mouse; Categories; Cell Maturation; Cells; Complement 3d; Complement 3d Receptors; Complement Receptor; Culture Media; Dendritic Cells; Dendritic cell activation; Development; Dose; Emerging Communicable Diseases; Fc Receptor; Follicular Dendritic Cells; Francisella tularensis; Generations; Goals; Growth; Heart; Human; Immune; Immunologist; In Vitro; Infection; Infectious Agent; Infusion procedures; Investigation; Ligands; Mediating; Metric; Microbe; Modality; Modeling; Mus; Organism; Pathogenesis; Preventive Medicine; Process; Public Health; Respiratory Tract Infections; Signal Transduction; Smallpox Vaccine; Stream; Surface; T-Lymphocyte; TLR2 gene; Testing; Vaccines; Virulent; adaptive immunity; base; biothreat; cytokine; extracellular; genetic manipulation; improved; in vivo; innovation; microbial; mucosal vaccine; novel; pathogen; public health relevance; response; success; vaccine development; vaccine efficacy

DESCRIPTION (provided by applicant): Establishment of an effective and uniform vaccine development strategy such as we propose here is key to conquering current and emerging infectious diseases. Despite successes against an array of bacterial agents, current approaches to vaccine development are as diverse as the microbes they target and require adjuvants that often have limited efficacy and/or toxic side effects. As a consequence, vaccine discovery is often slow, inefficient, and unsuccessful in the case of many high priority pathogens. We propose/hypothesize that vaccine generation for bacterial pathogens can be unified and stream-lined through a highly innovative criteria-directed approach that maximizes three of the most important criteria for vaccine success: Antigen (Ag)-mimicry, Adjuvanticity, and Efficient targeting of immunogens to Antigen Presenting Cells (APCs). We will test our hypothesis in the context of a very stringent model (respiratory infection with human-virulent Francisella tularensis [Ft]) in which we have obtained highly encouraging results with an adjuvant-free, mucosal vaccine (up to 75% protection of C57BL/6 mice). In fact, this is the only instance thus far in which it has been demonstrated that inactivated Ft administered intranasally protects C57BL/6 mice against mucosal challenge with the highly virulent Category A Ft SchuS4 pathogen. Thus, we will use Ft SchuS4 as a model pathogen to establish a criteria-directed approach to vaccine development, which we strongly believe will result in a fully protective adjuvant-independent mucosal vaccine against Ft SchuS4. In Aim 1, we will use differential cultivation and genetic manipulation of Ft SchuS4 to modulate: i) the antigenic similarity between in vitro- cultivated Ft immunogen and the replicating infectious pathogen (host-adaptation), ii) the cell-stimulatory capacity of the immunogen via over-expression of TLR2 agonist, and iii) processing/presentation of immunogen via bacterial surface expression of C3d, a ligand for CR2 on APCs (B cells and follicular dendritic cells). In Aim 2, we will analyze the impact of: i) growt medium-induced host-adaptation, and ii) over- expression of TLR2 ligands on TLR2 signaling, as reflected in dendritic cell (DC) maturation and cytokine responses. The impact of antigenic host-adaptation and altered TLR2 signaling on the processing/presentation of immunogen to Ft-specific T cells by DCs will also be evaluated. In Aim 3, we will: i) determine and optimize the protective activity of immunogens generated in Aims 1-2, separately and in combination, and ii) optimize the efficiency of Ft immunogen processing/presentation via the targeting of immunogen to CR2 and/or Fc receptors on APCs. The most protective immunogen(s) will then be evaluated in wildtype and humanized mice via aerosol challenge and correlates/mechanisms of protection identified. This project will not only yield an adjuvant-free mucosal vaccine against a Category A biothreat agent, but will establish an innovative and unique criteria-directed approach/platform for vaccine development applicable to other infectious agents, thus profoundly impacting preventive medicine/public health and changing the paradigm for vaccine development.

描述（由申请人提供）：建立一个有效和统一的疫苗开发策略，如我们在这里提出的，是征服当前和新出现的传染病的关键。尽管针对一系列细菌制剂取得了成功，但目前的疫苗开发方法与其靶向的微生物一样多样化，并且需要通常具有有限功效和/或毒副作用的佐剂。因此，在许多高优先级病原体的情况下，疫苗发现通常是缓慢、低效和不成功的。我们提出/假设，细菌病原体的疫苗生成可以通过高度创新的标准导向的方法来统一和简化，该方法最大限度地提高了疫苗成功的三个最重要的标准：抗原（Ag）模拟，佐剂性和免疫原有效靶向抗原呈递细胞（APC）。我们将在一个非常严格的模型（人毒性土拉弗朗西斯菌的呼吸道感染）中检验我们的假设 [Ft])其中，我们用不含杀虫剂的粘膜疫苗获得了非常令人鼓舞的结果（C57 BL/6小鼠的保护率高达75%）。事实上，这是迄今为止唯一一个证明鼻内给予灭活Ft可保护C57 BL/6小鼠免受高毒力A类Ft SchuS 4病原体粘膜攻击的实例。因此，我们将使用Ft SchuS 4作为模型病原体来建立疫苗开发的标准导向方法，我们坚信这将导致针对Ft SchuS 4的完全保护性的不依赖于病原体的粘膜疫苗。在目标1中，我们将使用Ft SchuS 4的差异培养和遗传操作来调节：i）体外培养的Ft免疫原和复制的感染性病原体之间的抗原相似性（宿主适应），ii）通过TLR 2激动剂的过表达的免疫原的细胞刺激能力，和iii）通过C3 d的细菌表面表达的免疫原的加工/呈递，APC（B细胞和滤泡树突细胞）上CR2的配体。在目的2中，我们将分析以下的影响：i）生长培养基诱导的宿主适应，和ii）TLR 2配体对TLR 2信号传导的过表达，如树突状细胞（DC）成熟和细胞因子应答中所反映的。还将评估抗原宿主适应和改变的TLR 2信号传导对DC将免疫原加工/呈递给Ft特异性T细胞的影响。在目标3中，我们将：ii）通过免疫原靶向APC上的CR2和/或Fc受体，优化Ft免疫原加工/呈递的效率。然后通过气溶胶激发在野生型和人源化小鼠中评价最具保护性的免疫原，并鉴定保护的相关性/机制。该项目不仅将产生针对A类生物威胁因子的无毒性粘膜疫苗，而且将建立适用于其他传染性因子的疫苗开发的创新和独特的标准导向方法/平台，从而深刻影响预防医学/公共卫生并改变疫苗开发的范式。