Animal Models of P. Vera

维拉动物模型

• 批准号: 7113541
• 负责人: Jerry L Spivak
• 金额: $ 31.64万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-06 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7113541
• 关键词: CD34 molecule; JAK kinase; NOD mouse; SCID mouse; clinical research; disease /disorder model; embryonic stem cell; flow cytometry; gene expression profiling; genetic models; genetically modified animals; hematopoiesis; hematopoietic stem cells; human subject; immunophenotype; model design /development; myelofibrosis; polycythemia vera; xenotransplantation

Polycythemia vera (PV) is a clonal disorder of unknown etiology arising in a multipotent hematopoietic progenitor cell that is characterized by overproduction of phenotypically normal red cells, white cells and platelets in the absence of a definable cause. Impaired expression of the thrombopoietin receptor, Mpl. occurs in PV and to a lesser extent, idiopathic myelofibrosis (IM) and essential thrombocytosis (ET), while in African Americans, an Mpl point mutation (K39N) was associated with thrombocytosis. Recently, a JAK2 point mutation (V617F) was identified in the majority of PV patients and also in some IM and ET patients. The extent to which each of these molecular abnormalities contributes to the PV phenotype and their relationship to each other is unknown but we hypothesize that both contribute and are integrally related. Using gene expression profiling and unsupervised hierarchical clustering in PV peripheral blood CD34+ cells, we have also been able to segregate PV patients into two groups: those with an aggressive disease and those with a more indolent one. Whether these gene expression profiles reflect the functional behavior of the CD34+ cells and how they relate to the JAK2 V617F mutation is unknown. To address these questions, we plan to develop complementary murine models to study the in vitro and in vivo behavior of murine hematopoietic progenitor cells expressing PV variant Mpl or JAK2 V617F alone or together using the Mpl knockout mouse to dissect Mpl and JAK2 V617F interactions. To control for overexpression of either Mpl or JAK2 V617F, we also plan to examine their behavior using conditional expression in murine ES cells from the Mpl knockout mouse. To examine the functional significance of the gene expression profiles, we plan to study the engraftment kinetics of PV CD34+ cells, their lineage-specific commitment and the extent of extramedullary hematopoiesis after transplantation into NOD-SCID mice. Using flow cytometry and xenotransplantation, we also plan to define by immunophenotyping, the class of CD34+ cell involved in PV. PV is not a new disease but after 11 decades of investigation, its etiology remains unknown and there is no specific therapy for it. We propose to develop complementary animal models for PV that will lead to an understanding of the pathogenesis of PV, that will identify PV patients most at risk from disease complications, and provide a means for testing potential treatments for the disorder.

真性红细胞增多症 (PV) 是一种病因不明的克隆性疾病，发生于多能造血系统 祖细胞，其特征是表型正常的红细胞、白细胞和 血小板在没有明确原因的情况下。血小板生成素受体 Mpl 的表达受损。 发生于PV，并在较小程度上发生特发性骨髓纤维化（IM）和特发性血小板增多症（ET），而在 非裔美国人中，Mpl 点突变 (K39N) 与血小板增多症相关。最近，JAK2 在大多数 PV 患者以及一些 IM 和 ET 患者中发现了点突变 (V617F)。 这些分子异常对 PV 表型的影响程度及其 彼此之间的关系尚不清楚，但我们假设两者都有贡献并且是整体相关的。 在PV外周血CD34+细胞中使用基因表达谱和无监督层次聚类， 我们还能够将真性红斑狼疮患者分为两组：患有侵袭性疾病的患者和患有侵袭性疾病的患者 那些比较懒惰的人。这些基因表达谱是否反映了功能行为 CD34+ 细胞及其与 JAK2 V617F 突变的关系尚不清楚。为了解答这些问题，我们 计划开发互补的小鼠模型来研究小鼠的体外和体内行为 单独或使用 Mpl 一起表达 PV 变体 Mpl 或 JAK2 V617F 的造血祖细胞 敲除小鼠来剖析 Mpl 和 JAK2 V617F 相互作用。控制 Mpl 或 Mpl 的过度表达 JAK2 V617F，我们还计划使用小鼠 ES 细胞中的条件表达来检查它们的行为 Mpl 基因敲除小鼠。为了检查基因表达谱的功能意义，我们计划 研究 PV CD34+ 细胞的植入动力学、其谱系特异性承诺和程度 移植到 NOD-SCID 小鼠后的髓外造血。使用流式细胞术和 异种移植中，我们还计划通过免疫表型来定义参与 PV 的 CD34+ 细胞类别。 PV 并不是一种新疾病，但经过 11 年的研究，其病因仍不清楚， 没有针对它的具体疗法。我们建议开发 PV 的补充动物模型，这将导致 了解真性红斑狼疮的发病机制，从而确定最有患病风险的真性红斑狼疮患者 并发症，并提供一种测试该疾病潜在治疗方法的方法。