Moezzi L, Pourfathollah A A, Alimoghaddam K, Soleimani M, Ardjmand A R
Iranian Blood Transfusion Organization, Tehran, Iran.
Transplant Proc. 2005 Dec;37(10):4500-3. doi: 10.1016/j.transproceed.2005.10.107.
Umbilical cord blood progenitor cells have been demonstrated to possess significant advantages over bone marrow in terms of proliferative capacity and immunologic reactivity. But the low number of hematopoeitic stem cells (HSC) is the most important limitation of its use. The ex vivo expansion of cord blood progenitor cells is the current strategy to overcome this problem. Furthermore, among the factors that enable successful cord blood transplantation is the ability to store and subsequently recover a sufficient number of viable cells. Since it would be costly to expand umbilical cord blood (UCB) progenitor cells, it is important to determine the feasibility and reproducibility of progenitor cell expansion after cryopreservation. We evaluated whether cryopreservation procedures might impair the clonogenic capacity and in vitro expansion of UCB.
We evaluated the cell viability, clonogenic capacity, CD34+38- content and in vitro expansion potential of progenitor cells from UCB (n = 10) separated mononuclear cells (MNC), before and after 1 month of cryopreservation by programmed rate freezing.
Although cell viability decreased after cryopreservation (P < .05), there was no significant difference in CD34+ or CD34+38- absolute count, colonogenic capacity and in vitro expansion potential of cord blood progenitor cells (P > .05).
Since the survival of CD34+ cells was greater than other elements, CD34+ cells seem more tolerant to cryopreservation than the other nucleated populations. Moreover in vitro expansion of UCB progenitor cells may be obtained following cryopreservation. Our results suggest that cryopreservation procedures do not impair the clonogenic capacity and in vitro expansion potential of cord blood stem/progenitor cells.
已证实脐带血祖细胞在增殖能力和免疫反应性方面比骨髓具有显著优势。但造血干细胞数量少是其应用的最重要限制。脐带血祖细胞的体外扩增是克服这一问题的当前策略。此外，成功进行脐带血移植的因素之一是能够储存并随后恢复足够数量的活细胞。由于扩增脐带血祖细胞成本高昂，因此确定冷冻保存后祖细胞扩增的可行性和可重复性很重要。我们评估了冷冻保存程序是否会损害脐带血的克隆形成能力和体外扩增能力。
我们评估了通过程序降温冷冻保存1个月前后，从脐带血（n = 10）分离的单个核细胞（MNC）中祖细胞的细胞活力、克隆形成能力、CD34 + 38 - 含量和体外扩增潜力。
尽管冷冻保存后细胞活力下降（P <.05），但脐带血祖细胞的CD34 + 或CD34 + 38 - 绝对计数、集落形成能力和体外扩增潜力没有显著差异（P >.05）。
由于CD34 + 细胞的存活率高于其他细胞成分，CD34 + 细胞似乎比其他有核细胞群体对冷冻保存更耐受。此外，冷冻保存后可实现脐带血祖细胞的体外扩增。我们的结果表明，冷冻保存程序不会损害脐带血干/祖细胞的克隆形成能力和体外扩增潜力。
