High-resolution single cell profiling of vaccine responsiveness in the elderly

项目摘要 本项目的目标是了解衰老相关的免疫细胞基因组和功能的变化， 影响流感疫苗接种反应的细胞。衰老的免疫系统的能力下降， 对疫苗的保护性反应是对老年人健康、独立和生存的主要威胁。多 关于这种下降机制的知识已经从集中于一种或几种免疫抑制剂的研究中获得。 细胞亚群或批量转录组学。然而，这项工作没有产生两个关键信息： 1)随着衰老，相关免疫细胞群体的集体变化的综合视图，以及2） 将特异性免疫细胞亚群与其潜在的细胞表型/转录谱联系起来的能力，以及 以比较这些表型和概况作为年龄和对疫苗的反应性的函数。单细胞 分析，我们使用的术语包括流式细胞术和质谱术以及单细胞RNAseq（scRNAseq）， 独特地定位于去卷积免疫系统异质性并鉴定新的独特免疫细胞 健康和疾病的子集。因此，单细胞分析将使我们能够解析免疫细胞亚群 与老年人对来自PBMC的疫苗的免疫应答相关的缺陷， 细胞群，但具有临床可及性、高度代表性和 最终不带偏见的数据生成和分析的目的。我们已经证明我们可以识别 从PBMC中分离出衰老的细胞类型特异性免疫特征，即使当这些免疫亚群代表 总PBMC池的一小部分，并且具有来自老年PBMC的初步单细胞谱数据， 强调可行性。在这里，我们将在单细胞水平上分析老年供体的PBMC， 接种疫苗后（目标1），以及有或没有特异性免疫亚群的体外活化（目标2），以了解 作为年龄和疫苗的函数， 响应能力。该提案基于我们在人类免疫学方面公认的专业知识， 细胞计数和单细胞转录组学分析（JAX-GM）方面的基本专业知识，以及对老年人群的访问 （乔治库切尔，康州大学老龄化中心）。影响：这些研究将以前所未有的分辨率产生 细胞类型特异性免疫特征，区分流感疫苗的应答者和非应答者， 为成功的疫苗免疫反应的机制和生物标志物提供了关键线索。 此外，这些研究将产生大量的转录和功能数据， 参与老年人流感疫苗应答的关键先天免疫和T/B细胞亚群的输出 个体这些数据将成为未来研究老年人免疫系统的重要资源， 疾病

PROJECT SUMMARY The goal of this project is to understand the aging-related genomic and functional changes in immune cells that affect responses to flu vaccination. The declining ability of the aging immune system to mount protective responses to vaccines is a major threat to the health, independence and survival of older adults. Much knowledge into the mechanisms of this decline has been gained from studies focused on one or a few immune cell subsets, or on bulk transcriptomics. However, this work has not produced two critical pieces of information: 1) an integrated view of the collective changes across relevant immune cell populations with aging, and 2) the ability to link specific immune cell subsets with their underlying cellular phenotypes/transcriptional profiles, and to compare these phenotypes and profiles as a function of age and responsiveness to vaccines. Single cell profiling, a term we use to encompass flow and mass cytometry together with single cell RNAseq (scRNAseq), is uniquely positioned to deconvolve immune system heterogeneity and identify novel distinct immune cell subsets in health and disease. Single cell profiling will therefore enable us to resolve the immune cell subset deficits relevant to the elderly immune response to vaccines from PBMCs, a highly heterogeneous starting population of cells, but one that offers the advantages of being clinically accessible, highly representative and ultimately unbiased for the purposes of data generation and analysis. We have shown that we can identify discreet cell-type-specific immune signatures of aging from PBMCs, even when such immune subsets represent a small fraction of the total PBMC pool, and have preliminary single cell profiling data from elderly PBMCs, underscoring feasibility. Here, we will analyze PBMCs at the single cell level from elderly donors before and after vaccination (Aim 1), and with or without in vitro activation of specific immune subsets (Aim 2), to understand the coordinated transcriptional and functional changes that occur, or fail to, as a function of age and vaccine responsiveness. This proposal builds on our recognized expertise in human immunology and incorporates essential expertise in cytometry and single cell transcriptomic analysis (JAX-GM), and access to elderly cohorts (George Kuchel, UConn Center on Aging). Impact: These studies will yield, with unprecedented resolution, the cell-type-specific immune signatures that distinguish responders to flu vaccine from non-responders, and will provide critical clues into the mechanisms and biomarkers of a successful vaccine immune response. Furthermore, these studies will generate a considerable amount of transcriptional and functional data related to the outputs of key innate immune and T/B-cell subsets involved in the influenza vaccine response of elderly individuals. The data will be an important resource for future studies of the elderly immune system in health and disease.