Studies of differentiation mechanisms of hematopoietic stem cells using cytokine-receptor transgenic mice

利用细胞因子受体转基因小鼠研究造血干细胞分化机制

基本信息

批准号：
10307020
负责人：
NAKAHATA Tatsutoshi
金额：
$ 24.83万
依托单位：
KYOTO UNIVERSITY (1999)The University of Tokyo (1998)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

Granulocyte-macrophage colony stimulating factor (GM-CSF) stimulates proliferation and maturation of myeloid progenitor cells through cell surface receptors expressed on target cells. To analyze the relationship between receptor expression and differentiation of hemopoietic cells, transgenic mice (Tg mice) which express hGMR at all stages of hemopoitic cell development were generated using hGMR α and β cDNAs. hGM-CSF supported colony formation of various types including blast cell, erythroid (E), megakaryocyte (Meg), and mixed hematopoietic colonies. Administration of hGM-CSF to Tg mice resulted in increase of not only neutrophils, monocyte, eosinophils, NK cells but also erythrocytes in their peripheral blood. To clalify whether GM-CSFR signaling can compensate erythropoietin receptor (EPOR) signaling in erythropoiesis, we next generated double mutant mice, hGM-CSFR+/+ and EPOR-/-. Although double mutant mice were embryonic lethal, hGM-CSF induced a large number of erythroid colonies from day 14 fetal liver cells of double mutant mice. We also generated Tg mice that had ubiquitous expressions of wild type human G-CSFR, wild type murine G-CSFR. In methylcellulose colony assay of bone marrow and spleen cells G-CSF have an effect on promoting the proliferation and differentiation of not only granulocyte but also macrophage, megakaryocyte, mast cells, erythroid and more primitive hematopoietic progenitors in both serum-containing and -free culture. These results shows that when functional GM-CSFR or G-CSFR are present on the cell surface, both cytokines does not induce exclusive commitment to the neutrophil and macrophage lineages. In vitro and in vivo studies using the Tg mice indicated that cytokines such as hGM-CSF or hG-CSF supported the growth of various hematopoietic progenitors when the receptor was expressed, but did not alter their commitment program, thus favoring the "stochastic model" rather than the "deterministic model".

粒细胞巨噬细胞集落刺激因子（GM-CSF）通过靶细胞上表达的细胞表面受体刺激骨髓祖细胞的增殖和成熟为了分析受体表达与造血细胞分化之间的关系，表达hGMR的转基因小鼠（Tg小鼠）。使用 hGMR α 和 β cDNA 生成造血细胞发育的所有阶段，支持各种类型的集落形成，包括母细胞、红细胞 (E)、巨核细胞（Meg）和混合造血集落给 Tg 小鼠施用 hGM-CSF 不仅导致其外周血中中性粒细胞、单核细胞、嗜酸性粒细胞、NK 细胞的增加，还导致红细胞的增加，以阐明 GM-CSFR 信号传导是否可以补偿促红细胞生成素。红细胞生成中的受体（EPOR）信号传导，我们接下来生成了双突变小鼠，hGM-CSFR+/+ 和虽然双突变小鼠是胚胎致死的，但 hGM-CSF 从双突变小鼠的第 14 天胎儿肝细胞中诱导出大量红细胞集落。，野生型小鼠G-CSFR在骨髓和脾细胞的甲基纤维素集落测定中不仅具有促进粒细胞增殖和分化的作用，而且还具有促进巨噬细胞增殖和分化的作用。这些结果表明，当功能性 GM-CSFR 或 G-CSFR 存在于细胞表面时，两种细胞因子不会诱导对巨核细胞、肥大细胞、红细胞和更原始造血祖细胞的排他性承诺。使用 Tg 小鼠进行的中性粒细胞和巨噬细胞谱系研究表明，hGM-CSF 或 hG-CSF 等细胞因子支持各种造血细胞的生长。当受体表达时，祖细胞被表达，但没有改变它们的承诺程序，因此有利于“随机模型”而不是“确定性模型”。