三种不同来源的CD_(34)^+细胞中的长期培养起始细胞含量的研究

LTC IC counts in CD + 34 cells from 3 different sourses in children

目的研究三种不同来源的长期培养起始细胞（ＬＴＣ－ＩＣ）是否存在含量区别。方法应用ｄｅｘｔｅｒ方法，在６种细胞因子刺激下，对正常骨髓、动员后的外周血以及脐带血的ＣＤ＋３４细胞中的ＬＴＣ－ＩＣ进行评价。结果ＣＤ＋３４细胞中的ＬＴＣ－ＩＣ含量以脐带血为最高，与外周血和骨髓相比差异有显著意义（Ｐ＜０．０１）。但将每毫升标本中所含的ＬＴＣ－ＩＣ绝对值相比，由于脐带血中单个核细胞（ＭＮＣ）和ＣＤ＋３４细胞率均较低，则ＬＴＣ－ＩＣ绝对值反而最低。经统计学处理，脐带血和外周血的ＣＤ＋３４细胞中的ＬＴＣ－ＩＣ的含量和每毫升中ＬＴＣ－ＩＣ的绝对值并无相关关系（经回归分析，脐带血ｒ＝０．１９８，外周血ｒ＝０．６８９，Ｐ值均＞０．０５）。但正常骨髓中二者却有显著相关关系（ｒ＝０．８９８，Ｐ＜０．０１）。从ＭＮＣ数、ＣＤ＋３４细胞率、ＣＦＣ（克隆形成细胞）以及ＬＴＣ－ＩＣ等方面对成人和小儿进行比较差异无显著意义。结论三种不同来源的定向和多能造血干细胞的比例不一致。

Objective To study whether there′s any difference in LTC IC counts from 3 different sources of the hematopoietic stem cells. Methods The authors studied LTC IC changes in CD + 34 cells from normal marrow, peripheral blood after mobilization and the cord blood under the stimulation of 6 kinds of cytokines with the Dexter cell long term culture assay. Results There was a significant difference in LTC IC counts in CD + 34 cells from the cord blood in comparison with those in the peripheral blood and bone marrow ( P < 0.01). But, if they analysed the absolute counts in each millilitre sample, due to the lower collection rate of the MNC and CD + 34 cells in cord blood, the absolute counts of LTC IC was the lowest. With the statistical treatment, there′s not any correlation between the LTC IC counts and the absolute counts of the LTC IC in each millilitre in the CD + 34 cells from cord blood or peripheral blood (regression analysis: r =0.198 in cord blood; r =0.689 in peripheral blood, P >0.05). But in normal marrow, there′s a significant association between LTC IC counts and the absolute counts of LTC LC in each millilitre. Conclusion The proportion of the progenitor and multi potential hematopoietic stem cells from those 3 different souces was not always accordant. Hence, attention must be paid to evaluate LTC IC counts and the absolute counts in CD + 34 cells in the clinical stem cells transplantation. So far, no significant difference has been found in the counts of MNC, the collection rate of CD + 34 cells, clone forming cells and LTC IC between adults and children.