Signaling via MHC: engineering immune cells with new capabilities

通过 MHC 发出信号：改造免疫细胞使其具有新功能

• 批准号: 10472922
• 负责人: Alok joglekar
• 金额: $ 138.38万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-07 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10472922
• 关键词: Adaptive Immune System; Antigen-Presenting Cells; Antigenic Specificity; Antigens; Autoimmune Diseases; Biological Models; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; Cells; Communicable Diseases; Complex; Disease; Effectiveness; Engineering; Epitopes; Experimental Models; Genes; Immune; Immunity; Immunologic Monitoring; Lead; Length; Link; Major Histocompatibility Complex; Malignant Neoplasms; Modality; Molecular; Natural Killer Cells; Organ Transplantation; Outcome; Peptide/MHC Complex; Peptides; Play; Role; Signal Transduction; Specificity; Surface; Synthetic immunology; T cell response; T-Cell Receptor; T-Lymphocyte; Therapeutic; Tissues; arm; autoreactivity; cancer transplantation; cellular engineering; combat; combinatorial; cytotoxic CD8 T cells; diagnostic tool; extracellular; frontier; immunoengineering; novel; novel diagnostics; novel therapeutics; pathogen; receptor; response; tool; tumor

ABSTRACT T cells constitute an essential arm of the adaptive immune system, protecting against pathogens and tumors, while tolerating self-tissues. Dysregulation of T cell responses can lead to infectious diseases, cancers, or autoimmune disorders. The key to the effectiveness of T cells is their exquisite antigenic specificity, which can be harnessed to combat diseases. T cells use their surface T cell receptor (TCR) to recognize peptide epitopes on Major Histocompatibility Complex (MHC) molecules (pMHC). While signaling through the TCR and its consequences have been studied extensively, pMHC is conventionally seen as merely a ‘flag’ on target cells for recognition by T cells. MHC molecules do not have canonical intracellular signaling domains, and therefore do not elicit any function into the cells presenting them, making TCR-pMHC interaction a ‘one-way street’ in terms of functional response. This presents a unique engineering opportunity: can TCR-pMHC interactions become ‘two-way streets’? Here, we hypothesize that if pMHC complexes are augmented with signaling domains, they can elicit signaling cascades, leading to expression of response genes that will cause cell-intrinsic functional changes, ultimately leading to cell-extrinsic functional changes. To that end, we will use the engineering platform developed by my group: Signaling and Antigen-presenting Bifunctional Receptors (SABRs). SABRs consist of extracellular full-length MHC complexes with genetically (and hence covalently) linked epitopes, fused with intracellular signaling domains. SABRs can present epitopes to T cells and elicit intracellular signaling upon successful recognition, thereby converting TCR-pMHC interactions into ‘two-way streets. In this proposal, we aim to wield SABRs to impart novel functional capabilities to immune and non-immune cells, thereby opening a new frontier of immune engineering and synthetic immunology. We will first lay out a framework for developing SABRs as a cellular engineering platform to empower combinatorial engineering of immune and non-immune cells to achieve desired immune outcome. We will describe three immune applications of SABRs: 1) engineering of cytotoxic CD8+ T cells or Natural Killer (NK) cells to eliminate autoreactive CD4+ T cells, 2) engineering professional Antigen-Presenting Cells (APCs) to modulate self-reactive or anti-tumor CD8+ T cell responses, 3) engineering CD8+ T cells to sense endogenous immunity to specific antigens and induce a secondary function, leading to a ‘read-and-react’ molecular circuit. These studies will create cellular therapeutic modalities, immune monitoring and perturbation tools, experimental model systems and uncover new immune phenomena. These studies will have profound implications on study and treatment of a wide range of diseases – autoimmune disorders, infectious diseases, cancers, and organ transplantations. 1

抽象的 T 细胞构成适应性免疫系统的重要组成部分，可防御病原体和肿瘤， 同时容忍自体组织。 T 细胞反应失调可能导致传染病、癌症或 自身免疫性疾病。 T细胞发挥功效的关键在于其精湛的抗原特异性，可以 可以用来对抗疾病。 T 细胞利用其表面 T 细胞受体 (TCR) 识别肽表位 主要组织相容性复合体 (MHC) 分子 (pMHC)。通过 TCR 及其信号发出信号时 其后果已被广泛研究，pMHC 传统上仅被视为靶细胞上的“标志” T细胞识别。 MHC 分子不具有典型的细胞内信号传导结构域，因此 不会对呈现它们的细胞产生任何功能，使得 TCR-pMHC 相互作用成为一条“单向街” 的功能反应。这提供了一个独特的工程机会：TCR-pMHC 相互作用能否成为 ‘双向街道’？在这里，我们假设如果 pMHC 复合物通过信号传导域增强，它们 可以引发信号级联反应，导致反应基因的表达，从而引起细胞内在功能 变化，最终导致细胞外在功能的变化。为此，我们将使用工程平台 由我的团队开发：信号和抗原呈递双功能受体（SABR）。 SABR 包括 细胞外全长 MHC 复合物，具有遗传（因此共价）连接的表位，并与 细胞内信号传导域。 SABR 可以向 T 细胞呈递表位并引发细胞内信号传导 成功识别，从而将 TCR-pMHC 相互作用转化为“双向街道”。在这个提案中，我们 旨在利用 SABR 为免疫和非免疫细胞赋予新的功能能力，从而开启 免疫工程和合成免疫学的新领域。我们首先会制定一个开发框架 SABR 作为细胞工程平台，支持免疫和非免疫的组合工程 细胞以达到预期的免疫结果。我们将描述 SABR 的三种免疫应用：1）工程 细胞毒性 CD8+ T 细胞或自然杀伤 (NK) 细胞以消除自身反应性 CD4+ T 细胞，2) 工程 专业抗原呈递细胞 (APC) 调节自身反应或抗肿瘤 CD8+ T 细胞反应，3) 改造 CD8+ T 细胞以感知针对特定抗原的内源性免疫并诱导次级功能， 形成“读取并反应”的分子电路。这些研究将创建细胞治疗方式、免疫治疗 监测和扰动工具、实验模型系统并发现新的免疫现象。这些 研究将对多种疾病的研究和治疗产生深远的影响——自身免疫性疾病 疾病、传染病、癌症和器官移植。 1