Initial CD34+ Cell-Enrichment of Cord Blood Determines Hematopoietic Stem/Progenitor Cell Yield Upon Ex Vivo Expansion
Initial CD34+ Cell-Enrichment of Cord Blood Determines Hematopoietic Stem/Progenitor Cell Yield Upon Ex Vivo Expansion
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DOI：
10.1002/jcb.23099
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发表时间：
2011-07-01
影响因子：
4
通讯作者：
Cabral, Joaquim M. S.
中科院分区：
文献类型：
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作者：
Andrade, Pedro Z.;da Silva, Claudia Lobato;Cabral, Joaquim M. S.
由于脐带血 (UCB) 含有有限的造血干细胞/祖细胞 (HSC) 数量，因此需要成功的扩增方案来克服与收集用于移植的 HSC 数量不足相关的障碍。使用基于人基质的无血清培养系统进行 UCB 培养，以评估不同的初始 CD34(+) 细胞富集（低：24 +/- 1.8%，中：46 +/- 2.6%，高：91 +/- 1.5%）对培养动态和 HSC 扩增结果的影响。通过将 PKH 追踪染料与 CD34(+) 和 CD34(+)CD90(+) 表达相结合，我们发现在细胞分裂之前（第 1 天分别为 35 +/- 4.7% 和 55 +/- 4.1% CD34(+) 细胞），低和中条件下 CD34(-) 细胞上 CD34 表达的早期激活，影响增殖/细胞周期状态并最终确定扩增 7 天后，CD34(+)/CD34(+)CD90(+) 细胞产量（高：14 +/- 1.0/3.5 +/- 1.4 倍；中：22 +/- 2.0/3.4 +/- 1.0 倍；低：31 +/- 3.0/4.4 +/- 1.5 倍）。考虑到在移植中使用扩增的 UCB HSC 的潜在好处，这里我们以单个 UCB 单位量化了使用一/两个免疫磁性分选周期（对应于中和高初始祖细胞含量）的影响，以及每种策略的平均 CD34(+) 细胞回收率对总体 CD34(+) 细胞扩增的影响。一个分选周期中较高的细胞回收率导致扩增 7 天后 CD34(+) 细胞数量较高（30 +/- 2.0 与 13 +/- 1.0 x 10(6) 细胞）。特别是，高（> 90％）的初始祖细胞含量并不是成功扩增HSC所必需的，因为具有中等富集水平的细胞群很容易在体外增加CD34表达，从而产生更高的干/祖细胞产量。总体而言，我们的研究结果强调了在细胞增殖潜力和纯化后细胞恢复之间建立平衡的重要性，以实现有效且经济有效地扩展 HSC 用于细胞治疗。 J.细胞。生物化学。 112: 1822-1831, 2011。(C) 2011 Wiley-Liss, Inc.
Since umbilical cord blood (UCB), contains a limited hematopoietic stem/progenitor cells (HSC) number, successful expansion protocols are needed to overcome the hurdles associated with inadequate numbers of HSC collected for transplantation. UCB cultures were performed using a human stromal-based serum-free culture system to evaluate the effect of different initial CD34(+) cell enrichments (Low: 24 +/- 1.8%, Medium: 46 +/- 2.6%, and High: 91 +/- 1.5%) on the culture dynamics and outcome of HSC expansion. By combining PKH tracking dye with CD34(+) and CD34(+)CD90(+) expression, we have identified early activation of CD34 expression on CD34(-) cells in Low and Medium conditions, prior to cell division (35 +/- 4.7% and 55 +/- 4.1% CD34(+) cells at day 1, respectively), affecting proliferation/cell cycle status and ultimately determining CD34(+)/CD34(+)CD90(+) cell yield (High: 14 +/- 1.0/3.5 +/- 1.4-fold; Medium: 22 +/- 2.0/3.4 +/- 1,0-fold; Low: 31 +/- 3.0/4.4 +/- 1.5-fold) after a 7-day expansion. Considering the potential benefits of using expanded UCB HSC in transplantation, here we quantified in single UCB units, the impact of using one/two immunomagnetic sorting cycles (corresponding to Medium and High initial progenitor content), and the average CD34(+) cell recovery for each strategy, on overall CD34(+) cell expansion. The higher cell recovery upon one sorting cycle lead to higher CD34(+) cell numbers after 7 days of expansion (30 +/- 2.0 vs. 13 +/- 1.0 x 10(6) cells). In particular, a high (>90%) initial progenitor content was not mandatory to successfully expand HSC, since cell populations with moderate levels of enrichment readily increased CD34 expression ex-vivo, generating higher stem/progenitor cell yields. Overall, our findings stress the importance of establishing a balance between the cell proliferative potential and cell recovery upon purification, towards the efficient and cost-effective expansion of HSC for cellular therapy. J. Cell. Biochem. 112: 1822-1831, 2011. (C) 2011 Wiley-Liss, Inc.