多潜能造血祖细胞向红系分化中GM-CSF受体和红细胞生成素受体的表达

CHANGES IN ERYTHROPOIETIN RECEPTOR AND GRANULOCYTEMACROPHAGE COLONY-STIMULATING FACTOR RECEPTOR EXPRESSIONS DURING ERYTHROID DIFFERENTIATION OF PLURIPOTENT CELL LINE UT-7

目的：了解多潜能造血祖细胞向红系分化过程中造血因子受体的改变。方法；应用受体结合实验和Northern杂交技术分别测定了依赖Epo和GM－CSF增殖的造血相细胞株UT－7在Epo存在下向红系分化过程中Epo受体（EpoR）和GM－CSF受体（GM－CSF－R）及其mRNA的表达水平。结果；UT－7分化至红系阶段Epo－R表达明显上调，而高亲合力和中亲和力GM－CSF－R明显下调。结论：UT－7分化至红系阶段丧失对GM－CSF反应性是由于Epo促使GM－CSF－R-α和β亚单位表达下调所致。提示增加Epo－R和减少GM－CSF－R表达是Epo诱导髓系相细胞向红系分化的重要原因。

Objective: To understand the changes in hematopoietic growth factor receptors during erythroid differentiation of pluripotent cells. Methods: Expressions of erythropoietin receptor (Epo-R)and granulocyte-macrophage colony-stimulating factor receptor(GM-CSF-R) were examined using receptor binding assay and Northern blot analysis during erythroid differentiation of the pluripotent cell line UT7 in the presence of Epo. Results: Epo-R expression was up-regulated, but the high and intermediate affinity GM-CSF-Rs were down-regulated when UT-7 differentiates to early erythroblasts. Conclusion:Loss of responsiveness to GM-CSF in this cell line may be due to down-regulation of α and β subunits and result in less GM-CSF-R formation. Thus, up-regulation of Epo-R and down-regulation of GMCSF-R expressions may play an important role in erythroid differentiation of pluripotent cells induced by Epo.