体外培养脐血单个核细胞与CD34+富集细胞

对比MNC和CD34 +富集细胞在SCF +IL 3+IL 6 +FL +Tpo细胞因子组合下的体外扩增特性 ,发现 :CD34 +富集细胞具有很高的扩增潜力 ,在本实验条件下其总细胞持续扩增了 8周 ,扩增倍数达 312 70 9± 86 40 5倍 ;而MNC在培养至第 4周扩增就已呈现下降趋势 ,最大仅扩增了 5 3 3± 6 2倍。对比集落和CD34 +细胞的扩增发现 ,MNC的集落密度和CD34 +细胞含量由第 0天至第 7天有一个上升的过程 ,而CD34 +富集细胞在培养过程中 ,集落密度和CD34 +细胞含量却始终呈下降趋势。在体外培养过程中 ,CD34 +富集细胞的CFU GM和CD34 +细胞最大分别扩增了 185 7± 14 1和 191 7± 188 8倍 ,明显高于MNC的 12 4± 3 2和 5 0 6± 33 2倍 ;而CD34 +富集细胞和MNC的BFU E则只实现了少量扩增 ,分别为 7 2± 5 2和 10 1± 3 4倍。结果显示 ,从CD34 +富集细胞出发扩增造血干 祖细胞 ,可以得到更多的CD34 +细胞和CFU GM集落形成细胞

In vitro Culture of Umbilical Cord Blood MNC and CD34+ Selected Cells

For in vitro studies, both CD34+ selected cell and mononuclear cell (MNC) can be used to expand hematopoietic stem/progenitor cells. To investigate the expansion characteristics of mononuclear cells (MNC) and CD34+ selected cells the two cell fractions were cultured in the medium containing cytokine cocktails of SCF + IL-3 + IL-6 + FL + Tpo. It was found that the CD34+ selected cells had presented a high proliferation potential. The expansion of CD34+ selected cells could be maintained for 8 weeks while that of MNCs declined after 4 weeks. During the culture period, the maximum expansion of total cells in CD34+ selected cell culture achieved 31,270.9 +/- 8640.5 times, while that of MNC reached 50.9 +/- 8.2 times only. In the culture of MNCs, the colony density and the proportion of CD34+ cells increased from day 0 to day 7. However, in the culture of CD34+ selected cells, both the colony density and the proportion of CD34+ cells declined continuously during the whole culture period. During the ex vivo culture of CD34+ selected cells, the maximum expansion of CFU-GM and CD34+ cells achieved 185.7 +/- 14.1 fold and 191.7 +/- 188.8 fold, respectively. They are much higher than that of MNC, which were 12.4 +/- 3.2 fold and 50.6 +/- 33.2 fold only. While the BFU-E of both cell fractions only expanded by few times, which were 7.2 +/- 5.2 and 10.1 +/- 3.4 times, respectively. The results showed that the CD34+ selected cells culture could obtain more CFU-GM cells and CD34+ cells during the whole culture period.