Defining immunological mechanisms of serovar cross-reactivity to develop broad spectrum protective vaccines for typhoidal and non-typhoidal Salmonella infections in humans

定义血清型交叉反应的免疫学机制，以开发针对人类伤寒和非伤寒沙门氏菌感染的广谱保护性疫苗

• 批准号: 10584484
• 负责人: Marcelo B. Sztein
• 金额: $ 90.67万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-15 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10584484
• 关键词: 3-Dimensional; Address; Advanced Development; Antigen Presentation; Antigen-Presenting Cells; Area; Attenuated; B-Lymphocytes; Bacteremia; Bacteria; Bacterial Infections; Biomedical Engineering; CD8-Positive T-Lymphocytes; Cells; Cellular Immunity; Characteristics; Circulation; Clinical; Cytometry; Data; Dendritic Cells; Development; Disease; Epidemiology; Epigenetic Process; Epithelial Cells; Event; Exposure to; Fever; Food Contamination; Generations; Genetic; Geographic Distribution; Goals; Human; Immune; Immune response; Immunity; Immunologics; In Vitro; Individual; Infection; Ingestion; Innate Immune Response; Intestines; Lead; Macrophage; MicroRNAs; Modeling; Multi-Drug Resistance; Oral; Organism; Organoids; Outcome; Pathway interactions; Peripheral Blood Mononuclear Cell; Phenotype; Play; Predisposition; Public Health; Resistance; Resources; Role; Salmonella; Salmonella infections; Salmonella paratyphi; Salmonella typhi; Salmonella typhimurium; Serotyping; Southeastern Asia; Specimen; System; T cell response; T-Lymphocyte; Technology; Typhoid Fever; Typhoid Vaccine; Vaccinated; Vaccination; Vaccines; Water; adaptive immune response; antimicrobial; cross reactivity; effector T cell; gastrointestinal infection; molecular marker; neutrophil; non-typhoidal Salmonella; passive antibodies; pathogen; pathogenic bacteria; prevent; response; transcriptomics; vaccine access; vaccine candidate; vaccine development; volunteer

ABSTRACT (CETR RP5, Sztein, PL) Infection with Salmonella spp. due to ingestion of contaminated food and water, including typhoidal (caused largely by S. Typhi (ST) and S. Paratyphi A (PA)), as well as non-typhoidal (NTS) and invasive NTS (iNTS) infections are major public health concerns in many areas of the World, including in the U.S. where NTS causes 1.2 million illnesses annually. The rapid increase in multidrug resistance (MDR) and the lack of vaccines against PA, NTS or iNTS have added a new sense of urgency for the development of vaccines against these pathogens, and ideally broad-spectrum vaccines. One of the major obstacles in developing vaccines against Salmonella spp. is that the precise immunological correlates of protection (CoP) against either infection with wild-type (wt) organisms or vaccines remain unknown, in part because ST and PA are human-restricted infections. The use of specimens from volunteers vaccinated and/or challenged with wt ST has begun to uncover immunological T cell-mediated immunity (T-CMI) effector mechanisms which might be associated with clinical outcome following challenge. No similar data is available for PA since the first wt PA challenge has just been performed. A critical gap also remains in our understanding of the mechanisms of antigen presentation for different Salmonella spp., which may underlie the development of effective adaptive T- CMI and B cell responses, as well as the immune responses elicited in the gut microenvironment following exposure to typhoidal and NTS infections. For these reasons, the overall goal of this application is to advance the development of vaccines against PA as well as broad-spectrum vaccines against enteric fevers, iNTS, and NTS, by identifying protective cross- reactive Salmonella spp. humoral, T effector, and regulatory immune responses, both systemically and in the gut microenvironment, and by defining the mechanisms of antigen presentation against ST, PA, iNTS and NTS that impact adaptive immune cell programming. To achieve these goals we will use PBMC from (i) a challenge study with wt PA with known clinical outcomes (e.g., non-disease or disease), (ii) a study with attenuated PA vaccine candidate strain CVD 1902 followed by challenge with wt PA, (iii) in vitro T cell priming systems and (iv) three human intestinal models: (a) bioengineered 3-D organoids, (b) enteroids, and (c) explants to perform the following Aims: Aim 1. Evaluate whether a defined set of B and T cellular responses in circulation are associated with protection from bacteremic infection and/or bacteremia-negative clinical disease (e.g., fever) following an oral challenge with wt PA in humans, and which regulatory mechanisms are involved in generating these responses. Aim 2. Evaluate whether interactions between ST, PA, iNTS and NTS and dendritic cells (DC) lead to the activation of diverse pathways which in turn determine the priming of defined T cell responses. Aim 3. Contrast molecular biomarker changes and function elicited in gut innate immune cells by various Salmonella serovars and the corresponding isogenic vaccine strains.

摘要（CETR RP5，Sztein，PL） 沙门氏菌感染。由于摄入受污染的食物和水，包括伤寒 （主要由伤寒沙门氏菌 (ST) 和甲型副伤寒沙门氏菌 (PA) 引起），以及非伤寒 (NTS) 和侵袭性 NTS (iNTS) 感染是世界许多地区的主要公共卫生问题，包括在美国。 每年导致 120 万人患病。多重耐药性（MDR）的迅速增加和缺乏 针对PA、NTS或iNTS的疫苗为疫苗开发增添了新的紧迫感 针对这些病原体，最好是广谱疫苗。发展的主要障碍之一 沙门氏菌疫苗是保护（CoP）的精确免疫相关性 野生型 (wt) 生物体的感染或疫苗仍然未知，部分原因是 ST 和 PA 人类限制性感染。使用来自接受 wt ST 疫苗接种和/或攻击的志愿者的标本 已经开始揭示免疫学 T 细胞介导的免疫 (T-CMI) 效应机制，这可能是 与挑战后的临床结果相关。自第一个 wt PA 以来，没有类似的 PA 数据 挑战刚刚完成。我们对机制的理解也存在一个关键差距 不同沙门氏菌属的抗原呈递，这可能是有效适应性 T- 发展的基础 CMI 和 B 细胞反应，以及肠道微环境中引发的免疫反应 接触伤寒和 NTS 感染。 出于这些原因，本申请的总体目标是推进疫苗的开发 PA 以及针对肠热病、iNTS 和 NTS 的广谱疫苗，通过识别保护性交叉 反应性沙门氏菌体液、T 效应子和调节性免疫反应，无论是全身性的还是在 肠道微环境，并定义针对 ST、PA、iNTS 和 NTS 的抗原呈递机制 影响适应性免疫细胞编程。为了实现这些目标，我们将使用 PBMC 应对 (i) 挑战 具有已知临床结果（例如非疾病或疾病）的 wt PA 研究，(ii) 减毒 PA 研究 候选疫苗株 CVD 1902，然后用 wt PA 攻击，(iii) 体外 T 细胞引发系统和 (iv) 三种人类肠道模型：(a) 生物工程 3-D 类器官、(b) 肠类器官和 (c) 外植体 目标如下： 目标 1. 评估循环中一组定义的 B 和 T 细胞反应是否 与预防菌血症感染和/或菌血症阴性临床疾病（例如发烧）有关 在人类中口服 wt PA 后，以及哪些调节机制参与产生 这些回应。目标 2. 评估 ST、PA、iNTS 和 NTS 与树突状细胞之间是否存在相互作用 (DC) 导致多种途径的激活，进而决定特定 T 细胞反应的启动。 目标 3. 对比各种因素在肠道先天免疫细胞中引起的分子生物标志物变化和功能 沙门氏菌血清型和相应的同基因疫苗株。