Combination Adjuvants to Activate Human Dendritic Cell Subsets and B Cells

 说明(申请人提供)：接种疫苗是预防传染病最有效的方法。目前的许多疫苗都是“灭活疫苗”或“亚单位”疫苗，由纯化的或重组的病原体成分组成，通常添加佐剂以增加抗体反应的幅度。然而，用目前FDA批准的佐剂配制的亚单位疫苗不能充分提高某些人群的免疫力，特别是免疫受损和老年受试者。近年来发现了许多佐剂，它们作为单一佐剂表现出增强的免疫原性；然而，人们对它们组合的活性、安全性、有效性及其作用机制知之甚少。 行动的一部分。对疫苗和佐剂的应答涉及树突状细胞(DC)，树突状细胞捕获并呈递疫苗抗原，从而促进滤泡辅助T细胞(TFH)和B细胞的分化和随后的体液免疫。因此，我们建议研究体外和体内联合佐剂对人DC亚群的分子机制和功能输出。鉴于小鼠和人类在先天性免疫受体分布和功能上的巨大差异，对人类DC的关注是必不可少的。我们的目标是通过功能分析选择一种联合佐剂，然后深入研究免疫原性增强的分子途径。我们与产业界的合作将使选定的联合佐剂能够过渡到进一步的人类疫苗接种研究。我们的具体目标就是朝着这个目标而建立的。因此，首先，我们将通过评估佐剂激活的人DC亚群的能力来筛选佐剂组合，以扭曲初始的CD4+T细胞向分泌IL-21的TFH细胞的分化，并诱导B细胞产生IgG和IgA抗体(目标1)。有希望的组合将在DC中进一步研究，使用经过验证的、敏感的和高通量转录表观基因组、蛋白质组和代谢组学方法，并通过体外功能敲除来确定佐剂疗效的潜在分子途径(目标2)。然后，我们将使用携带功能重组的人类免疫系统的人源化小鼠，通过在体内进行功能敲除研究来验证已确定的分子途径，这也将使检查可能的副作用成为可能(目标3)。拟议的研究计划将利用尖端表观遗传学(ATAC-SEQ)、转录、基因编辑(CRISPR/CAS9)和新陈代谢技术；创新的人源化小鼠模型；杰克逊实验室强大的计算和生物信息学基础设施；以及充满活力的研究团队的补充专业知识。我们提供的是一种增强体液免疫和分子途径的联合佐剂，这是其疗效所必需的。

 DESCRIPTION (provided by applicant): Vaccination is the most effective method for preventing infectious diseases. Many current vaccines are "inactivated" or "subunit" vaccines composed of purified or recombinant pathogen components to which an adjuvant is often added to increase the magnitude of antibody responses. However, subunit vaccines formulated with current FDA-approved adjuvants do not sufficiently boost immunity in some populations, particularly immunocompromised and elderly subjects. Numerous adjuvants have been discovered in recent years and show enhanced immunogenicity as single agents; however, little is known about the activity of their combination, their safety, their efficacy and their mechanisms of action. Responses to vaccination and adjuvants involve dendritic cells (DCs), which capture and present vaccine antigens thereby facilitating the differentiation of follicular helper T cells (Tfh) and B cells and subsequent humoral immunity. Therefore, we propose to examine the molecular mechanisms and functional outputs of human DC subsets exposed to combination adjuvants ex vivo and in vivo. The focus on human DCs is essential given the substantial differences in innate immune receptor distribution and function between the mouse and the human. Our goal is to select a combination adjuvant using functional assays, followed by in-depth investigation of molecular pathways accounting for enhanced immunogenicity. Our collaboration with industry will enable the transition of the selected combination adjuvant to further studies of human vaccination. Our Specific Aims are built towards this goal. Thus, first we will screen adjuvant combinations by assessing the capacity of adjuvant-activated human DC subsets to skew the differentiation of naïve CD4+T cells into Tfh cells that secrete IL-21 and induce B cells to produce IgG and IgA antibodies (Aim 1). Promising combinations will be further studied in DCs using validated, sensitive and high-throughput transcriptomic epigenomic, proteomic and metabolomic methods, and by functional knockdown in vitro, to determine the underlying molecular pathways of adjuvant efficacy (Aim 2). We will then validate the identified molecular pathways through functional knockdown studies in vivo using humanized mice carrying a functionally reconstituted human immune system, which will also enable the examination of possible side effects (Aim 3). The proposed research program will leverage cutting-edge epigenetic (ATAC-seq), transcriptional, gene editing (CRISPR/Cas9) and metabolomic technologies; innovative humanized mouse models; a powerful computational and bioinformatics infrastructure at The Jackson Laboratory; and the complementary expertise of a dynamic team of investigators. Our deliverable is a combination adjuvant for enhanced humoral immunity and molecular pathways that are essential for its efficacy.