Yamamura Y, Noda M, Ikawa Y
Department of Biochemistry, Tokyo Medical and Dental University School of Medicine, Japan.
Leukemia. 1994 Apr;8 Suppl 1:S107-10.
Erythropoietin (EPO) regulates proliferation and differentiation and prevents apoptosis of erythroid progenitor cells by binding to erythropoietin receptor (EPOR) expressed on the surface of those cells. The mechanism by which EPO signal is transmitted to the cells through EPOR is still unclear. In the present study, we introduced and expressed EPOR in an interleukin-3 (IL-3) dependent pro-B cell line, BAF-B03 and an interleukin-2 (IL-2)-dependent cytotoxic T cell line, CTLL-2 and analyzed their growth response to EPO and the DNA breakdown characteristic to apoptosis after deprivation of the growth factor. BAF-B03-derived cells expressing EPOR proliferated in response to EPO but CTLL-2-derived cells expressing EPOR (C/EPOR) did not. DNA from C/EPOR cells cultured in the absence of IL-2 with or without EPO had similar patterns of DNA breakdown. These results suggest that downstream signaling pathways for the cell proliferation and apoptosis-block are, at least, partially different between EPOR and IL-2 receptor (IL-2R).
促红细胞生成素（EPO）通过与红细胞生成素受体（EPOR）结合来调节红细胞祖细胞的增殖和分化，并防止其凋亡，EPOR表达于这些细胞的表面。EPO信号通过EPOR传递至细胞的机制仍不清楚。在本研究中，我们在依赖白细胞介素-3（IL-3）的前B细胞系BAF-B03和依赖白细胞介素-2（IL-2）的细胞毒性T细胞系CTLL-2中导入并表达了EPOR，并分析了它们对EPO的生长反应以及在生长因子缺失后凋亡的DNA降解特征。表达EPOR的BAF-B03来源细胞对EPO有增殖反应，但表达EPOR的CTLL-2来源细胞（C/EPOR）则没有。在有或没有EPO的情况下，在无IL-2条件下培养的C/EPOR细胞的DNA具有相似的DNA降解模式。这些结果表明，EPOR和白细胞介素-2受体（IL-2R）之间，至少在细胞增殖和凋亡阻断的下游信号通路部分存在差异。
