Project 4: APOB-specific CD4 and CD8 T cells exacerbate atherosclerosis

项目4摘要 本PPG中的项目4有4个项目和3个核心，重点关注T细胞对载脂蛋白B（Apo B）的应答， 一种动脉粥样硬化抗原。核心假设是自身免疫反应 最初具有动脉粥样硬化保护作用，但随着动脉粥样硬化的进展而变为促动脉粥样硬化（转变）。 我们将在有和没有冠状动脉疾病的人中解决这个问题（弗吉尼亚州心血管评估 [CAVA]和CT-CAVA组）和新产生的Apoe-/-FoxP3-ERT2-Cre-GFP ROSA 26-fl-STOP-fl- RFP谱系追踪小鼠。我们提出三个具体目标。目的1：确定ApoB特异性CD4和CD8 T细胞 来自CAD病例和对照的PBMC中的细胞。这包括T细胞转录组、TCR α和β序列、细胞 通过Ab-Seq检测表面表型，并找到它们应答的免疫显性ApoB表位。的 主要的方法有单细胞（sc）RNA-Seq、抗体（Ab）-Seq和T细胞受体（TCR）-Seq。找到 免疫显性表位，与基于细胞的和免疫调节疗法的关键相关性，我们将使用一种 208个MHC结合人ApoB肽的megapool，然后通过Elispot测试系统解卷积， 细胞内细胞因子染色（ICS）、细胞因子捕获测定（CCA）和抗原诱导的标志物（AIM）测定。 目的2是通过将新的小鼠模型与ApoB特异性T细胞结合来测试ApoB特异性T细胞如何发育。 四聚体。我们的初步数据支持这样的假设，即一些ApoB特异性CD4 T细胞已经存在于 非常年轻的老鼠。这些细胞中的一些是效应T细胞（非T细胞）。小鼠中的其他FoxP3 + CD4 + T细胞 随着动脉粥样硬化进展，其转录组从动脉粥样硬化保护性转变为促动脉粥样硬化性。 从机制上讲，我们将测试Treg到exTreg开关的代谢和表观遗传假设。目标3：测试 假设患有心血管疾病的人中的ApoB特异性T细胞包括TcB、exTcB和 使用scRNA-Seq和去卷积（CIBERSORT）方法，在非THBE中进行。当提议的工作完成后， 我们将知道人ApoB中主要的MHC-II限制性表位和应答T细胞的极化， 通过scRNA-Seq、Ab-Seq和TCR-Seq检测细胞。我们将了解Treg表型转换的机制以及Treg表型转换的机制。 PBMC中TcB、exTcB和其他ApoB特异性T细胞的比例（CAVA和CT-CAVA队列），以及 动脉内膜切除术转录组（BIKE队列）。

Project 4 Summary Project 4 in this PPG with 4 projects and 3 cores is focused on the T cell response to apolipoprotein B (ApoB), an atherosclerosis antigen, in humans and mice. The central hypothesis is that the autoimmune response is initially atheroprotective, but becomes pro-atherogenic (switches) as atherosclerosis progresses. We will address this in humans with and without coronary artery disease (Cardiovascular Assessment Virginia [CAVA] and CT-CAVA cohorts) and in newly generated Apoe-/- FoxP3-ERT2-Cre-GFP ROSA26-fl-STOP-fl- RFP lineage tracker mice. We propose 3 specific aims. Aim 1 is to define the ApoB-specific CD4 and CD8 T cells in PBMCs from CAD cases and controls. This includes T cell transcriptomes, TCRα and β sequences, cell surface phenotypes by Ab-Seq, and finding the immunodominant ApoB epitopes to which they respond. The main methods are single cell (sc) RNA-Seq, antibody (Ab)-Seq and T cell receptor (TCR)-Seq. To find the immunodominant epitopes, of key relevance for cell-based and immunomodulatory therapeutics, we will use a megapool of 208 MHC-binding human ApoB peptides, followed by systematic deconvolution tested by Elispot, intracellular cytokine staining (ICS), cytokine capture assays (CCA) and antigen-induced marker (AIM) assays. Aim 2 is to test how ApoB-specific T cells develop by combining the new mouse model with ApoB-specific tetramers. Our preliminary data support the hypothesis that some ApoB-specific CD4 T cells already exist in very young mice. Some of these cells are effector T cells (non-Tregs). Other FoxP3+ CD4+ Tregs in mice switch their transcriptomes from atheroprotective to pro-atherogenic with progression of atherosclerosis. Mechanistically, we will test the metabolic and epigenetic hypotheses of Treg to exTreg switch. Aim 3 is to test the hypothesis that ApoB-specific T cells in humans with cardiovascular disease include Tregs, exTregs and non-Tregs, using scRNA-Seq and deconvolution (CIBERSORT) methods. When the proposed work is done, we will know the dominant MHC-II-restricted epitopes in human ApoB and the polarization of responding T cells by scRNA-Seq, Ab-Seq and TCR-Seq. We will know the mechanism of Treg phenotype switching and the proportion of Tregs, exTregs and other ApoB-specific T cells in PBMCs (CAVA and CT-CAVA cohorts) and endarteriectomy transcriptomes (BIKE cohort).