Molecular Pathways Regulating Tissue-resident Memory T cells in the Gut

调节肠道组织驻留记忆 T 细胞的分子途径

基本信息

批准号：
10426457
负责人：
Michael Lawrence Dougan
金额：
$ 61.22万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-03-01 至 2027-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10426457
关键词：
Address Adrenal Cortex Hormones Advanced Malignant Neoplasm Adverse event Affect Antibodies Antibody Therapy Autoimmune Diseases Back Bar Codes Biopsy Biopsy Specimen Blocking Antibodies CD8-Positive T-Lymphocytes CTLA4 blockade CTLA4 gene Cancer Patient Cell Communication Cell physiology Cells Cellular Immunity Clinical Clinical Data Clinical Trials Clonal Expansion Colitis Colon Colonic inflammation Combined Modality Therapy Cytotoxic T-Lymphocytes DNA Data Development Diagnosis Diagnostic Dietary Proteins Enrollment Epithelial Cells FOXP3 gene Fc Receptor Formalin Funding Gene Expression Profile Goals Gut Mucosa Homeostasis Human Imaging Techniques Immune Immune checkpoint inhibitor Immunity Immunofluorescence Immunologic Immunologics Immunology Individual Inflammatory Intestinal Mucosa Invaded Lead Lung Memory Molecular Monoclonal Antibodies Mucous Membrane Mus Myeloid Cells Paraffin Embedding Pathogenesis Pathway interactions Patients Phase II Clinical Trials Physiological Population Pulmonary Inflammation Randomized Regulation Regulatory T-Lymphocyte Reporting Role Signal Transduction Small Intestines Specimen Stromal Cells Surface Suspensions T memory cell T-Cell Receptor T-Lymphocyte TNF gene Techniques Technology Therapeutic Therapeutic Agents Time Tissue Embedding Tissues anti-PD1 antibodies base checkpoint inhibition chemokine chemokine receptor commensal microbes cytokine cytotoxic cytotoxic CD8 T cells enteritis high dimensionality human model imaging approach immune checkpoint blockade immunoregulation insight intestinal homeostasis mouse model pathogen programmed cell death protein 1 receptor receptor function response single cell analysis single-cell RNA sequencing therapeutic target tool tumor-immune system interactions

项目摘要

Abstract The intestinal mucosa has a rich immune microenvironment capable of responding rapidly to invading pathogens while maintaining a regulated homeostatic state to commensal microbiota and dietary proteins. Tissue-resident memory T cells are critical for immune homeostasis at mucosal surfaces based on their ability to rapidly respond to invading pathogens. The CTLA-4 and PD-1 receptors inhibit T cell function and have become major therapeutic targets for boosting T cell-mediated immunity in cancer patients. However, targeting of these inhibitory receptors frequently induces inflammatory adverse events, and colitis is one of the most common and severe inflammatory adverse events induced by checkpoint inhibition (CPI). We recently reported an in-depth single cell analysis of immune cells in the mucosa of CPI colitis patients and healthy subjects. This analysis demonstrated dramatic accumulation of CD8 T cell populations with highly proliferative and cytotoxic states in all studied CPI colitis patients. We used the T cell receptor (TCR) sequences of CD8 T cells to investigate the origin of these clonally expanded T cells. Interestingly, we discovered that a large fraction of colitis-associated cytotoxic CD8 T cells had the same TCR sequences as tissue-resident memory CD8 T cells. We therefore hypothesize that the CTLA-4 and PD-1 inhibitory receptors hold tissue-resident memory T cells (Trm) in check, and that loss of these inhibitory signals can induce massive clonal expansion of Trm, a major step in the development of CPI colitis. Antibody blockade of CTLA-4 and PD-1 receptors in individuals with immunologically normal mucosa thus provides insight into the physiological function of these receptors in humans. In Aim 1, we will investigate how the CTLA-4 and PD-1 receptors regulate the function of Trm cells, both in humans and murine models. We will investigate whether targeting of inflammatory pathways may revert T cells from highly proliferative, cytotoxic states back into a Trm state by performing an in-depth single cell analyses on colon biopsies from CPI colitis patients enrolled in a separately funded randomized phase 2 clinical trial that evaluates TNFα blockade versus corticosteroids. Our single cell analysis demonstrated upregulated TNF gene expression signatures in CPI colitis, and retrospective clinical data indicate that TNFα blockade is efficacious in CPI colitis. We will also investigate this hypothesis in murine models by evaluating the impact of CTLA-4 and PD-1 antibodies on the activation and cytotoxic states of CD8 T cells in the gut mucosa. In Aim 2 we will study the spatial interactions of T cell populations with immune, epithelial and stromal cells in the intestinal mucosa using the CODEX technology that enables highly multiplexed immunofluorescence analysis of tissue sections using panels of DNA-barcoded mAbs. This high-dimensional imaging approach affords an opportunity to study the cell – cell interactions in the healthy gut mucosa and in CPI colitis, including biopsy specimens from the clinical trial described in Aim 1. This project thus addresses a fundamental question is mucosal immunology. 1

抽象的肠粘膜具有丰富的免疫环境，能够快速反应入侵病原体同时维持对共生微生物群和饮食蛋白的调节状态。组织居民记忆T细胞根据粘膜表面的免疫稳态至关重要入侵病原体。 CTLA-4和PD-1受体抑制T细胞功能，并已成为主要癌症患者中T细胞介导的免疫力的治疗靶标。但是，针对这些抑制受体经常诱发炎症性不良事件，结肠炎是最常见的事件之一，检查点抑制（CPI）引起的严重炎症性不良事件。我们最近报道了一个深入的 CPI结肠炎患者和健康受试者的粘膜中免疫细胞的单细胞分析。这个分析证明CD8 T细胞种群的急剧积累，具有高度增殖和细胞毒性状态所有研究的CPI结肠炎患者。我们使用CD8 T细胞的T细胞接收器（TCR）序列研究这些克隆扩展的T细胞的起源。有趣的是，我们发现大量与结肠炎相关的细胞毒性CD8 T细胞的TCR序列与组织驻留的记忆CD8 T细胞相同。因此，我们假设CTLA-4和PD-1抑制剂接收器将组织与居民记忆T细胞（TRM）保持在检查，这些抑制信号的丢失会诱导TRM的大规模克隆扩张，这是一个主要的踏上CPI结肠炎的发展。患有CTLA-4和PD-1受体的抗体阻断因此，免疫学上正常的粘膜可以深入了解这些受体在人类。在AIM 1中，我们将研究CTLA-4和PD-1受体如何调节TRM细胞的功能，在人类和鼠模型中。我们将调查针对炎症途径的靶向是否可能恢复通过执行深入的单细胞，来自高度增殖的细胞毒性状态的T细胞回到了TRM状态对分别资助的随机2阶段临床的CPI结肠炎患者的结肠活检的分析评估TNFα封锁与皮质类固醇的试验。我们的单细胞分析显示了更新 CPI结肠炎中的TNF基因表达特征以及回顾性临床数据，表明TNFαblocade是在CPI结肠炎中有效。我们还将通过评估鼠模型中的这一假设来评估肠粘膜中CD8 T细胞的激活和细胞毒性态的CTLA-4和PD-1抗体。在目标2中我们将研究T细胞群体与肠中免疫，上皮细胞和基质细胞的空间相互作用使用法典技术启用组织的高度多重免疫荧光分析的粘膜使用DNA-barcoded mabs面板的切片。这种高维成像方法提供了机会研究健康肠粘膜和CPI结肠炎中的细胞 - 细胞相互作用，包括来自 AIM 1中描述的临床试验。因此，该项目解决了一个基本问题是粘膜免疫学。 1