Enhancing the Effectiveness of Immunotherapies by T Cell Epigenetic Reprogramming

通过 T 细胞表观遗传重编程增强免疫疗法的有效性

• 批准号: 10737264
• 负责人: Hazem E. Ghoneim
• 金额: $ 64.01万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-05 至 2028-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10737264
• 关键词: Acceleration; Address; Adoptive Transfer; Agonist; Back; Biological Models; Breast Adenocarcinoma; CD8-Positive T-Lymphocytes; CRISPR/Cas technology; CTLA4 gene; Cancer Patient; Cell physiology; Cells; Chromatin; Chronic; Clinical; DNA Methylation; DNMT3a; Data; Effectiveness; Endowment; Enzymes; Epigenetic Process; Equilibrium; Failure; Functional disorder; Genes; Genetic Transcription; Glioma; Goals; Grant; Human; Immune response; Immunotherapy; In Vitro; Infection; Knowledge; Link; Lymphocytic choriomeningitis virus; Malignant Neoplasms; Mediating; Memory; Methods; Modeling; Molecular Target; Morbidity - disease rate; Mus; Nature; Pathway interactions; Patients; Pre-Clinical Model; Refractory; Rejuvenation; Reporting; Resistance; Role; Route; Signal Pathway; Signal Transduction; Specificity; System; T cell differentiation; T-Lymphocyte; Technology; Testing; Therapeutic; Transforming Growth Factor beta; Transgenic Organisms; Translating; Viral; Viral Cancer; Virus; Virus Diseases; antagonist; chromatin remodeling; chronic infection; cytotoxic; cytotoxic CD8 T cells; epigenome; exhaust; exhaustion; experimental study; functional restoration; immune checkpoint blockade; in vitro Model; in vivo; in vivo Model; insight; melanoma; mortality; novel; novel strategies; prevent; progenitor; programmed cell death protein 1; programs; receptor; refractory cancer; response; restraint; retroviral transduction; stem; stemness; success; synergism; tool; transcriptome; tumor

PROJECT SUMMARY Cancer and chronic virus infections are significant causes of morbidity and mortality. While cytotoxic CD8 T cells are the main killers of tumors or virus-infected cells, persistent stimulation of CD8 T cells during chronic infections or cancer results in a gradual loss of their cytotoxic function as T cells progress towards a fully- exhausted state. While immune checkpoint blockade (ICB) therapy allows partially-exhausted CD8 T cells to functionally recover by blocking inhibitory signals, terminally-exhausted T cells remain nonresponsive to this therapy. The inability of terminally-exhausted T cells to recover after ICB may explain why many cancer patients fail to mount durable responses to ICB. We recently showed that de novo DNA methylation programming is causally linked to the progression of T cells toward terminal exhaustion and poor response to ICB. Importantly, we discovered that targeting T cell-intrinsic epigenetic programs synergized the efficacy of ICB during chronic infection or cancer. Yet, the following questions represent major gaps in our current understanding of T cell exhaustion: (1) How are these epigenetic changes acquired in exhausted T cells? (2) What are the upstream signals that regulate the specificity of de novo DNA methylation programs in exhausted versus functional T cells? (3) Can we reverse the epigenetic programming in exhausted T cells to the functional state while avoiding transformation? Bridging these gaps will allow us to identify and target factors that apply “epigenetic brakes” to CD8 T cell function. To address these questions, we have developed a novel in-vitro model of stable human T cell dysfunction as a tractable tool that can guide our in-vivo experiments by providing first-line mechanistic studies. First, we will employ cutting-edge approaches, such as CRISPR-Cas9 gene editing and retroviral transduction, to test the hypothesis that specific tumor microenvironmental signals regulate epigenetic programming in persistently stimulated CD8 T cells, which promotes their resistance to ICB therapy. We aim to block and/or revert the progression toward the terminally-exhausted state by targeting components of this signaling pathway while promoting counteracting pathways. Second, we aim to rebalance specific microenvironmental signals to restore functionality and response in terminally-exhausted T cells. Using novel in- vitro model systems of T cell dysfunction and complementary in-vivo models of chronic viral infection and cancer, as well as cutting-edge technologies to profile DNA methylation, open chromatin landscape, and transcriptome in CD8 T cells, our proposed studies can determine if targeting specific factors can remodel chromatin back into an accessible state at effector and/or stemness-associated genes, leading to functionally-rejuvenated T cells. These proposed studies will provide insights into how epigenetic programming can be reversed during progression to T cell exhaustion that can be translated to reprogram terminally-exhausted T cells in clinical settings, ultimately enhancing the efficacy of T cell immunotherapies.

项目摘要 癌症和慢性病毒感染是发病率和死亡率的重要原因。而细胞毒性CD8 T 细胞是肿瘤或病毒感染细胞的主要杀手，在慢性期间持续刺激CD8 T细胞 感染或癌症导致其细胞毒性功能的年级丧失，因为T细胞朝着完全的发展 耗尽的状态。而免疫检查点阻滞（ICB）治疗允许部分竭尽全力的CD8 T细胞 在功能上通过阻止抑制信号恢复，终止尚竭尽全力的T细胞对此无反应 治疗。 ICB之后终端排定的T细胞无法恢复的能力可以解释为什么许多癌症患者 无法安装对ICB的持久响应。我们最近表明从头DNA甲基化编程是 因果关系与T细胞向终末疲劳的进展和对ICB的反应不佳。重要的是， 我们发现，针对T细胞中的表观遗传学程序的靶向使ICB的效率协同慢性 感染或癌症。但是，以下问题代表了我们当前对T细胞的理解中的主要差距 精疲力尽：（1）在耗尽的T细胞中如何获得这些表观遗传变化？ （2）上游是什么 在耗尽的T细胞和功能性T细胞中调节从头DNA甲基化程序的特异性的信号？ （3）我们可以将耗尽的T细胞中的表观遗传编程逆转到避免的功能状态 转型？桥接这些差距将使我们能够识别和针对应用“表观遗传制动”的因素 CD8 T细胞功能。为了解决这些问题，我们已经开发了一种新颖的体外模型稳定的人类T 细胞功能障碍是一种可拖动工具，可以通过提供一线机械来指导我们的体内实验 研究。首先，我们将采用尖端方法，例如CRISPR-CAS9基因编辑和逆转录病毒 转导，以测试特定肿瘤微环境信号调节表观遗传的假设 持续刺激CD8 T细胞的编程，从而促进了它们对ICB治疗的耐药性。我们的目标 通过针对此的组成部分，阻止和/或恢复向终端悬而未决的状态的进展 信号通路，同时促进抵抗路径。第二，我们的目标是重新平衡 微环境信号以恢复终末饮食T细胞中的功能和响应。使用新颖 T细胞功能障碍的体外模型系统和慢性病毒感染和癌症的完整体内模型， 以及介绍DNA甲基化，开放染色质景观和转录组的尖端技术 在CD8 T细胞中，我们提出的研究可以确定靶向特定因素是否可以重塑染色质 在效应子和/或与Stem相关的基因中可访问的状态，导致功能培养的T细胞。 这些拟议的研究将提供有关如何在期间如何逆转表观遗传编程的见解 可以将T细胞耗尽的进展转化为可以翻译成临床中终末悬而未决的T细胞 设置，最终提高了T细胞免疫疗法的效率。