TF-1细胞增殖特性与信号蛋白JAK2/STAT3表达研究

The Proliferation and Expression of Signal Molecules JAK2/STAT3 in TF-1 Cell Line

目的 探索JAK/STAT途径活化与细胞增殖和凋亡之间的关系。方法 通过表达内源性GM CSF受体的TF 1细胞 ,观察细胞增殖与凋亡 ;建立免疫沉淀和Westernblot印迹方法 ,检测经GM CSF 10 0ng/ml瞬时诱导的TF 1细胞信号蛋白JAK2和STAT3酪氨酸磷酸化情况。结果 经过GM CSF刺激 ,细胞不但免于凋亡 ,TF 1细胞还呈现剂量与时间信赖性的增殖反应。当耗竭细胞因子 6～ 12h后 ,倒置显微镜下TF 1细胞呈现折光性改变 ,细胞开始凋亡 ,呈现凋亡特征性形态改变和出现DNA梯形条带 ,而加入 0 .1ng/ml的GM CSF ,TF 1细胞即开始进入增殖状态 ,提示GM CSF对细胞具有凋亡保护作用。经过 10 0ng/mlGM CSF的瞬时诱导 ,在分子量 130kd区域见到JAK2蛋白条带 ,显示GM CSF可诱导TF 1细胞磷酸化JAK2表达 ;而在分子量 90kd区域未见到STAT3蛋白条带 ,显示无磷酸化STAT3表达 ;而未经GM CSF诱导的TF 1细胞 ,既无磷酸化JAK2也无磷酸化STAT3表达。结论 GM CSF为TF 1细胞增殖诱导和凋亡保护所必需 ;GM CSF诱导的TF

Objective To investigate the relationship between the activated JAK/STAT proteins and the proliferation of myeloid leukemic cells.Methods In human myeloid TF 1 cell line expressing the endogenous GM CSF receptor,immunoprecipitation and Western blot analysis were used to determine if there ware tyrosine phosphorylated JAK2 and STAT3 stimulated by GM CSF;Simultaneously the apoptotic and proliferative status was observed on the due time. Results In TF 1 cell line,the activation of JAK2 but not STAT3 was detected induced by GM CSF;Moreover this cell line was observed to proliferate in a dose and time dependent manner induced by GM CSF;In addition,GM CSF could protect TF 1 cells from apoptosis demonstrated by morphological alteration and DNA fragmentization. Conclusion GM CSF was essential for the protection of cells from apoptosis and the promotion of proliferation of TF 1 cells; Moreover,GM CSF induced biological effect was associated with the activation of JAK2; In addition,activated JAK/STAT signal pathway may be involved in the apoptosis and proliferation,which further confirmed the autocrine or paracrine mechanism of leukemogenesis.