Mechanisms of human pre-B cell differentiation

人类前B细胞分化的机制

• 批准号: 9102627
• 负责人: KATIA GEORGOPOULOS
• 金额: $ 24.64万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-15 至 2018-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9102627
• 关键词: Adhesions; Adult; Anoikis; B cell differentiation; B cell repertoire; B-Cell Acute Lymphoblastic Leukemia; B-Lymphocytes; Bone Marrow; Cell Adhesion; Cell Death; Cell surface; Chromatin; Data; Dependence; Development; Developmental Process; Disease; Drug resistance; Event; Fibronectins; Gene Expression; Gene Expression Profile; Gene Mutation; Generations; Genes; Genetic Recombination; Genetic Transcription; Goals; Heavy-Chain Immunoglobulins; Hematological Disease; Hematopoietic; Hematopoietic System; Human; IL7R gene; Immune; Immunologic Deficiency Syndromes; In Vitro; Integrins; Investigation; Knowledge; Ligands; Light; Lymphoid; Malignant - descriptor; Malignant Neoplasms; Mature B-Lymphocyte; Modeling; Molecular; Mus; Mutation; Pathway interactions; Phase; Phenotype; Process; Property; Receptor Signaling; Receptors, Antigen, B-Cell; Regulation; Role; Sampling; Signal Pathway; Signal Transduction; Site; Staging; System; Testing; Transplantation; Umbilical Cord Blood; Work; fetal; follow-up; genome editing; high risk; human disease; humoral immunity deficiency; in vivo; leukemia; mutant; novel strategies; pre-B cell receptor; prevent; progenitor; public health relevance; self-renewal; transcription factor

 DESCRIPTION (provided by applicant): Regulated transitions through early B cell differentiation are of great importance for the generation and selection of the mature B cell repertoire. We have recently described a transitional phase in early mouse B cell differentiation that in addition to pre-BCR and IL7R signaling also displays integrin-dependent stromal adhesion, strong proliferative capacity and self-renewal. Loss in the transcriptional regulator Ikaros causes arrest at this stromal- adherent pre-B cell stage with a profound increase in integrin signaling, stromal adhesion and self-renewal and loss in pre-BCR differentiation signaling. Although this stage of early B cell differentiation is also important for the developmen of human hematological disorders, including immunodeficiencies and leukemias, little is known of this process in the human hematopoietic system and is the focus of our current investigation. In the first aim, we will evaluate the hierarchy of human B cell precursors that arise in a bone marrow stromal-dependent system. We will examine the in vitro stromal dependence of early human B cell precursors for proliferative expansion and differentiation and identify the signaling pathways and transcriptional factors associated with these events. The differentiation properties of human B cell precursors generated in vivo in immune-deficient NSG mice will be evaluated in a similar fashion. In the second aim, we will examine the role of IKAROS in human pre-B cell differentiation. The IKZF1 locus will be disrupted by genome editing in human B cell precursors to model mutations in human disease. IKAROS mutant B cell precursors will be tested for differentiation, proliferation and adhesion properties in in vitro stromal cultures and in vivo aftr transplantation in NSG mice. Cellular and molecular data generated from IKAROS deficient human pre-B cell precursors and its normal counterparts can serve as baselines to which hematological disorders can be compared. Together these studies will generate critical new knowledge on the molecular pathways that drive the human developmental process and its aberrant manifestations. This work will enable us to move seamlessly between the mouse and human to discover better approaches for treating hematological disorders.

 描述（由申请人提供）：通过早期 B 细胞分化进行的调节转变对于成熟 B 细胞库的生成和选择非常重要。我们最近描述了小鼠早期 B 细胞分化的一个过渡阶段，除了前 BCR 和 IL7R 信号传导外，还表现出整合素依赖性基质粘附、强大的增殖能力和自我更新能力。转录调节因子 Ikaros 的缺失会导致细胞停滞在基质粘附的前 B 细胞阶段，并导致整合素信号、基质粘附和自我更新显着增加，以及前 BCR 分化信号的丧失。尽管早期 B 细胞分化的这一阶段对于人类血液疾病（包括免疫缺陷和白血病）的发展也很重要，但人们对人类造血系统中的这一过程知之甚少，这也是我们当前研究的重点。第一个目标是，我们将评估骨髓基质依赖性系统中产生的人类 B 细胞前体的层次结构。我们将检查早期人类 B 细胞前体的体外基质依赖性增殖扩张和分化，并确定与这些事件相关的信号传导途径和转录因子。免疫缺陷 NSG 小鼠体内产生的人类 B 细胞前体的分化特性将以类似的方式进行评估。第二个目标是研究 IKAROS 在人类前 B 细胞分化中的作用。 IKZF1 基因座将通过人类 B 细胞前体中的基因组编辑来破坏，以模拟人类疾病的突变。 IKAROS 突变 B 细胞前体将在体外基质培养物和 NSG 小鼠移植后的体内进行分化、增殖和粘附特性测试。从 IKAROS 缺陷的人类前 B 细胞前体及其正常对应物产生的细胞和分子数据可以作为血液疾病比较的基线。这些研究将共同​​产生关于驱动人类发育过程及其异常表现的分子途径的重要新知识。这项工作将使我们能够在小鼠和人类之间无缝移动，以发现治疗血液疾病的更好方法。