Project 3 - Differential contribution of thymic APCs to central tolerance during the perinatal to adult transition

项目 3 - 胸腺 APC 在围产期到成人过渡期间对中枢耐受的不同贡献

• 批准号: 10251300
• 负责人: Lauren Ilyse Richie EHRLICH
• 金额: $ 50.94万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10251300
• 关键词: Activities of Daily Living; Adolescent; Adult; Affinity; Age; Agonist; Antigen Presentation; Antigen-Presenting Cells; Antigens; Autoantigens; Autoimmune; Autoimmunity; Bioinformatics; Biological Assay; Biometry; Cell Compartmentation; Cell Differentiation process; Cells; Cellularity; Characteristics; Conflict (Psychology); Data; Dendritic Cells; Environment; Gene Expression; Gene Expression Profiling; Generations; Genetic Models; Genetic Transcription; Goals; Growth; Hematopoietic; Human; Impairment; Life; Location; Maps; Mediating; Molecular; Molecular Profiling; Mus; Organizational Change; Output; Perinatal; Phenotype; Play; Process; Property; Regulatory T-Lymphocyte; Reporting; Role; Self Tolerance; Slice; Stromal Cells; T cell response; T-Lymphocyte; Testing; Therapeutic; Thymic epithelial cell; Thymocyte Selection; Thymus Gland; Tissue imaging; Tissues; autoreactive T cell; autoreactivity; central tolerance; experimental study; multiplexed imaging; pathogen; perinatal period; programs; response; single-cell RNA sequencing; thymocyte; two photon microscopy

ABSTRACT Project 3 The perinatal thymus plays a unique role in promoting central tolerance. Central tolerance results from negative selection of autoreactive conventional T cells (Tconv) and differentiation of regulatory T cells (Treg). Notably, Tregs selected during the perinatal period are more autoreactive and are uniquely required for life- long protection against autoimmunity. Perinatal Tconv cells are also more autoreactive and have unique molecular and functional properties compared with their juvenile/adult counterparts. Both negative selection and Treg induction occur when thymocytes encounter auto-antigens presented by medullary thymic epithelial cells (mTECs) or hematopoietic antigen presenting cells (HAPCs), including dendritic cells (DCs). TECs and thymic HAPCs undergo profound changes during the perinatal to juvenile transition. The rationale for RP3 is that thymic HAPCs are distinct in cellular composition and molecular profiles in the perinatal period, when thymic selection is critical for differentiation of the first wave of Tconv cells and establishment of self-tolerance. We will test the hypothesis that unique properties of mTECs and HAPCs in the perinatal period create an altered environment for central tolerance induction and are responsible for selection of Tconv and Treg cells with increased self-reactivity and age-specific functional properties. In Aim 1, we will use single cell transcriptional profiling (scRNA-seq) and multiplex imaging to identify the cellular, transcriptional, and organizational changes that occur in mouse and human HAPCs over the perinatal to juvenile transition which could impact central tolerance. In Aim 2, we will use phenotypic analyses, transcriptional profiling, genetic models, and functional assays to identify the APCs responsible for selecting tissue-protective Treg in the perinatal period. We will also determine whether CCR7-mediated cross-talk with TECs alters the DC compartment in perinatal mice, with downstream consequences for Treg selection. In Aim 3, we will determine if negative selection is impaired in perinates in response to antigens across a range of affinities. Live-cell 2- photon microscopy will be used to determine if distinct APCs induce negative selection in the perinatal period. RP3 has multiple points of intersection with all Projects and Cores. We will use scRNA-seq to identify altered molecular signatures of HAPCs in mice and humans (with Cores B and C) during the perinatal to juvenile transition that could impact central tolerance. Parallel data from RP1 and RP2 will provide a comprehensive map of changes in TECs and thymic stromal cells over the perinatal to juvenile transtition that could to alter central tolerance. We will also collaborate with the Manley lab (RP2) for MiCasa analysis to reveal organizational changes in the thymic environment during the perinatal to juvenile transition. Results generated in RP3 are integral to achieving the overall Program goals of elucidating mechanisms by which thymic stromal properties alter Treg and Tconv cell differentiation and selection in the perinatal period, with implications for devising rational therapeutic strategies to safely enhance T cell output.

摘要项目3 围产期胸腺在促进中央耐受性中起着独特的作用。中心公差来自 自动反应性常规T细胞（TCONV）和调节T细胞（Treg）的分化负面选择。 值得注意的是，在围产期期间选择的Tregs具有更大的自动反应性，并且是生命的独特所必需的 长期保护自身免疫。围产期TCONV细胞也更具自动反应性，并且具有独特的 与少年/成年人相比，分子和功能特性。两种负面选择 当胸腺上皮呈现的胸腺细胞遇到自动抗原时，就会发生Treg诱导 细胞（MTEC）或造血抗原呈递细胞（HAPC），包括树突状细胞（DCS）。 tecs和 胸腺HAPC在围产期向青少年过渡期间发生了深刻的变化。 RP3的理由是 胸腺HAPC在围产期的细胞组成和分子特征中是不同的，当 胸腺选择对于区分第一波TCONV细胞和建立自我耐受至关重要。 我们将测试以下假设：MTEC和HAPC在围产期的独特特性创建一个 中央耐受诱导环境的改变，并负责选择TCONV和TREG细胞 具有增加的自我反应性和特定年龄的功能特性。在AIM 1中，我们将使用单个单元格 转录分析（SCRNA-SEQ）和多重成像，以识别细胞，转录和 鼠标和人类HAPC中发生的组织变化是对少年过渡的围产期的 可能会影响中心容忍。在AIM 2中，我们将使用表型分析，转录分析，遗传 模型和功能测定法以识别负责选择组织保护Treg的APC 围产期。我们还将确定CCR7介导的与TECS是否改变了DC 围产小鼠的隔室，对Treg选择有下游后果。在AIM 3中，我们将确定 如果对围绕一系列亲和力的抗原响应抗原而受到负面选择损害。活细胞2- 光子显微镜将用于确定在围产期期间不同的APC是否诱导负选择。 RP3与所有项目和核心都有多个交点。我们将使用scrna-seq识别 在围产期期间，小鼠和人类中HAPC的分子特征改变了（核B和C） 少年过渡可能会影响中心容忍。 RP1和RP2的并行数据将提供 TECS和胸腺基质细胞在围产期到少年transtition的综合图表 可以改变中央耐受性。我们还将与Manley Lab（RP2）合作进行云母分析 揭示围产期过渡期间胸腺环境中的组织变化。结果 在RP3中产生的是实现阐明机制的总体计划目标不可或缺的一部分 胸腺基质特性在围产期改变Treg和TCONV细胞分化和选择，与 制定理性治疗策略以安全增强T细胞输出的含义。