CD131基因在急性髓系白血病细胞的表达研究

Expression of CD131 Gene in Acute Myeloid Leukemic Cells

目的:检测急性髓系白血病细胞CD131基因表达水平及是否存在突变,分析CD131表达水平与急性髓系白血病临床特点的关系。方法:收集44例急性髓系白血病初治病人及25个正常人外周血单个核细胞,应用RTPCR比较二者CD131基因的表达水平;随机选取15例病人及5例正常人,采用PCR方法扩增CD131全长编码序列,连接到p GEM-T载体,转化Top10感受态细胞,筛选阳性克隆,序列分析检测二者CD131编码序列的突变情况。根据CD131的表达情况,将病例分为CD131阴性组和CD131阳性组,比较两组病例外周血白细胞数、CD34+细胞比例、化疗缓解率。结果:病例组的CD131基因表达水平显著低于正常对照组;序列分析检测到5种CD131的突变体,病例组的CD131的突变率为75.33%,显著高于正常对照组的突变率18.0%。CD131阴性组的CD34+细胞比例(69.1%±20.8%)显著高于CD131阳性组(27.7%±15.7%),化疗后完全缓解率(71.1%)低于CD131阳性组(33.3%)。两组外周血白细胞计数差别无统计学意义。结论:CD131基因在急性髓系白血病细胞中表达水平低且突变率高。不表达CD131的急性髓系白血病,其CD34+细胞比例高,化疗完全缓解率低。

Objective:To detect the expression level and the mutantion of CD131 in acute myeloid leukemic(AML)cells,and to analyze the relationship of CD131 expression level with clinical features.Methods:The peripheral blood mononuclear cells(PBMNC) from 44 AML patients and 25 healthy donors were collected,and the expression level of CD131 mRNA was detected by RT-PCR.The full length coding sequence of CD131 from 15 patients and 5 healthy donors was amplified by RT-PCR,and linked to pGEM-T vector to clone TA,10 positive recombinant clones of each sample were analyzed by DNA sequencing.The AML patients were divided into CD131 negative and CD131 positive groups according the expression level of CD131,and white blood cell counts,CD34 + cells percentage,complete remission rate of patients were compared.Results:CD131 was expressed at a lower level in AML than that in healthy donor.Five kinds of CD131 mutantions could be detected in both AML and healthy donor groups,but the mutation rate in AML(75.33%) was higher than that in healthy donors(18.0%).CD131 negative group showed a higher CD34 +cells percentage(69.1%± 20.8%),and lower complete remission rate(33.3%) than that in CD131 positive group(69.1%± 20.8%,33.3%).No statistically significant difference of WBC counts was found between 2 groups.Conclusion:CD131 is expressed at a low level and shows high frequency of mutation in acute myeloid leukemic cells.CD131 negative AML correlats with high proportion of CD34 + cells,and showed insensitive to chemotherapy.