Cellular and molecular analysis of B lymphocyte development and selection

B 淋巴细胞发育和选择的细胞和分子分析

• 批准号: 9060869
• 负责人: JOAO PEREIRA
• 金额: $ 41.47万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-15 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9060869
• 关键词: Aging; Architecture; Attention; Autoimmune Diseases; Autoimmunity; B-Cell Development; B-Lymphocytes; Behavior; Binding; Bone Marrow; Bone Marrow Cells; CXCL12 gene; CXCR4 gene; Cell Death; Cell Differentiation process; Cell Lineage; Cell Maintenance; Cell Shape; Cells; Clonal Deletion; Common Lymphoid Progenitor; Complex; Cues; Data; Defect; Development; Generations; Goals; Grant; Health; Hematopoietic; Hematopoietic stem cells; Homing; Human; Immature B-Lymphocyte; Immune System Diseases; Immune response; Immune system; Immunologic Deficiency Syndromes; Interleukin-7; Knock-in Mouse; Laboratories; Learning; Left; Life; Ligands; Light; Lymphocyte; Lymphoid; Lymphopoiesis; Maintenance; Mediating; Mesenchymal; Mesenchymal Stem Cells; Microanatomy; Microscope; Microscopy; Modeling; Molecular; Molecular Analysis; Mouse Strains; Movement; Mus; Mutation; Names; Organ; Organism; Pertussis Toxin; Phenocopy; Play; Positioning Attribute; Process; Proteins; Receptors, Antigen, B-Cell; Research; Role; Shapes; Signal Transduction; Specificity; Staging; Stem cells; Stromal Cells; Systemic Lupus Erythematosus; Testing; Transgenic Organisms; Work; cell motility; central tolerance; chemokine receptor; environmental change; migration; molecular dynamics; mouse model; multi-photon; novel therapeutic intervention; pathogen; progenitor; receptor; receptor coupling; stem; stem cell differentiation; transcription factor; two-photon

DESCRIPTION (provided by applicant): The quest for understanding lymphocyte migration challenged multiple laboratories for several decades now. The development of multi-photon microscopes has shed light on the dynamics of lymphocyte movement in secondary lymphoid organs. In contrast, very little is understood about the dynamics and cellular interactions instructing hematopoietic cell differentiation in bone marrow (BM). B lymphocytes develop from hematopoietic stem and progenitor cells within essential, yet poorly characterized, BM stromal cell niches. A significant body of work has focused on the lymphocyte-intrinsic mechanisms critical for lymphocyte development. Despite their importance, these studies led to lymphoid-centric working models that are insufficient for understanding the complex interactions between hematopoietic precursors and the BM stromal cells that instruct cell lineage decisions. Furthermore, there are currently no conceptual or mechanistic frameworks explaining the development and maintenance of lymphoid-supportive stromal cell niches in BM. In this grant we provide groundbreaking preliminary evidence for a critical role played by the chemokine receptor CXCR4 in BM stromal cells for the development of B-lineage supportive stromal cell niches. In aim 1, we propose to fully characterize the impact of CXCR4-deficiency, exclusively in BM stromal cells, on the maintenance and differentiation of wild-type hematopoietic stem cells. We will also determine how CXCR4 signaling instructs stromal niches to support B cell development in BM. In aim 2, we provide compelling evidence that hematopoietic precursor positioning in lymphoid-supportive stromal niches is a highly regulated process vital for B lymphocyte development. We will characterize the stromal cell niches that are critical for B lymphocyte lineage development. Furthermore, we will define guidance mechanisms attracting lymphoid progenitors to such lymphoid-supportive stromal niches. In late stages of B cell development, immature B lymphocytes undergo stringent central tolerance checkpoints in BM niches that eliminate self-reactive B cells by allowing cells to change their receptor specificity a process named receptor editing) or by promoting cell death (a process known as clonal deletion). In aim 3, we describe a strategy for visualizing B-lymphocyte clonal deletion and receptor editing by intravital 2-photon microscopy. We will use this approach to test the hypothesis that B lymphocyte migration and interactions with stromal cell niches enable B cell central tolerance, using available B cell receptor transgenic and knock-in mouse strains as well as established mouse models of the human autoimmune disease systemic lupus erythematosus. Together, the proposed aims will provide a broad conceptual and mechanistic framework for understanding how guidance cues shape the BM stromal cell compartment and influence cell lineage decisions during hematopoietic cell differentiation.

描述（由申请人提供）：对了解淋巴细胞迁移的追求已经挑战了数十年的多个实验室。多光子显微镜的发展揭示了次级淋巴器官中淋巴细胞运动的动力学。相反，关于指导骨髓（BM）中造血细胞分化的动力学和细胞相互作用的了解很少。 B淋巴细胞是由造血干和祖细胞在必不可少但表征较差的BM基质细胞壁ches中发展而来的。一项重要的工作集中在淋巴细胞内部机制上对淋巴细胞发育至关重要的机制。尽管它们的重要性，但这些研究导致了以淋巴样的工作模型，这些模型不足以理解造血前体和BM基质细胞之间的复杂相互作用，而BM基质细胞指导了细胞谱系的决策。此外，目前尚无概念或机械框架来解释BM中淋巴间基细胞壁细胞壁细胞的发展和维持。在这笔赠款中，我们提供了开创性的初步证据，证明了趋化因子受体CXCR4在BM基质细胞中发挥的关键作用，以开发B-linege辅助辅助性基质细胞壁ni。在AIM 1中，我们建议完全表征CXCR4缺陷的影响（仅在BM基质细胞中），对野生型造血干细胞的维持和分化。我们还将确定CXCR4信号传导如何指示基质生态位支持BM中的B细胞发育。在AIM 2中，我们提供了令人信服的证据，表明淋巴管支持的基质壁ches中的造血前体位置是对B淋巴细胞发育至关重要的高度调节过程。我们将表征对B淋巴细胞谱系发育至关重要的基质细胞壁ni。此外，我们将定义吸引淋巴祖细胞的引导机制，以这种淋巴管的基质壁ri。在B细胞发育的后期，未成熟的B淋巴细胞在BM壁ches中经历严格的中央耐受性检查点，通过允许细胞更改其受体特异性，从而消除了自反应B细胞，或通过促进细胞死亡（一种称为克隆删除的过程）。在AIM 3中，我们描述了一种可视化B-淋巴细胞克隆缺失和受体编辑的策略。我们将使用这种方法来测试B淋巴细胞迁移和与基质细胞壁细胞壁细分的相互作用的假说，可以使用可用的B细胞受体转基因和敲击小鼠菌株以及人类自身免疫性疾病全身性lupus reyythematosus的小鼠模型。拟议的目标将共同提供一个广泛的概念和机械框架，以了解指导如何塑造BM基质细胞室并影响造血细胞分化过程中细胞谱系决策。