脐血CD34^＋细胞分离方法比较

目的：比较不同方法分离脐血单个核细胞（MNC）及纯化CD34＋细胞效果。方法：采集脐血48份，在室温下保存12、24、48小时，分别用密度离心法和羟乙基淀粉（HES）沉淀法分离脐血MNC，再用免疫磁珠法纯化CD34^＋细胞，以台盼蓝拒染法检测细胞存活率。结果：脐血在室温下保存48小时分离MNC和CD34^＋细胞数最多．其次为12小时，在24小时分离所得最低（P〈0．05）；HES沉淀法较密度离心法分离所得MNC和CD34^＋细胞数明显增多（P〈0．05）；6组细胞存活率差异无统计学意义（P〉0．05）；免疫磁珠法纯化CD34^＋细胞可达（88±5）％的纯度。结论：HES沉淀法优于密度离心法，且48小时分离为优，免疫磁珠法纯化CD34＋细胞可提高纯度：各种方法对细胞存活率无明显影响。

Comparison on Methods of Separating CD34+ Cells from Umbilical Cord Blood

Objective: To compare the effects of separating mononuclear cells and purifying CD34+ cells with different methods. Methods: Collecting 48 cord blood units, separating mononuclear cells from cord blood by density centrifugal method and hydroxyethyl starch precipitation method after being stored for 12h, 24 h and 48h at room temperature(RT), purifying CD34+ cells with immunomagnetic beads, and assessing cell viability by typan blue staining. Results: The numbers of MNC and CD34+ cells were the largest when being separated after being stored for 48h at RT, smaller after being stored for 12h, and the smallest after being stored for 24h(P<0.05); more MNC and CD34+ cells could be separated by HES precipitation method than by density centrifugal method(P<0.05); there was no significant difference between the cell survival rates of the six groups(P>0.05); the purity of CD34+ cells could get to(88±5)% after being purified by immunomagnetic beads. Conclusions: Different separation methods have different effects; purifying CD34+ cells with immunomagnetic beads is convenient and reliable; there is no significant difference between the cell survival rates.