Kim Kyeong Mi, Huh Ji Young, Kim Jin Ju, Kang Myung Seo
Department of Laboratory Medicine, CHA Bundang Medical Center, CHA University, 59, Yatap-ro, Bundang-gu, Seongnam-si, Gyeonggi-do, South Korea.
Department of Laboratory Medicine, Inha University College of Medicine, 27, Inhang-ro, Jung-gu, Incheon, South Korea.
Cryobiology. 2017 Oct;78:65-69. doi: 10.1016/j.cryobiol.2017.07.001. Epub 2017 Jul 14.
Umbilical cord blood (CB) banks usually freeze and store CB for clinical transplantation using conventional controlled-rate freezer or the automated BioArchive system. The aim of this study is to compare the quality of CB cryopreserved with conventional and automated methods and to make clear the cause of the quality difference between the two methods. The experiment used 80 CB units: 40 were conventionally cryopreserved and the remainder were cryopreserved with a BioArchive. After thawing, the following measures of CB quality were compared: recovery rates of cell count, cell viability of total nucleated cells (TNCs), mononuclear cells (MNCs), and CD34+ cells, as well as colony-forming unit-granulocyte/macrophage (CFU-GM) content. Additionally, processing and storage records were reviewed to quantify the number of exposures of CB units at room temperature (transient warming event, TWE), which was analyzed in relation to CB quality. MNC and CD34+ cell viability were as follows: MNC, 78.2% ± 6.8% (conventional), 81.7% ± 7.2% (automated); CD34+ cell, 90.6% ± 6.9% (conventional), 94.7% ± 3.5% (automated). The absolute CFU-GM content per CB unit was 7.1 × 10 ± 5.9 × 10 with conventional cryopreservation and 12.3 × 10 ± 12.0 × 10 with automated cryopreservation. CBs cryopreserved with BioArchive showed significantly higher MNC and CD34+ cell viability, and CFU-GM content than those conventionally cryopreserved. The CB quality comparison depending on the amount of TWEs showed no significant quality difference between groups that were more exposed to TWEs and groups that were less exposed. CBs cryopreserved with BioArchive were of higher quality than conventionally cryopreserved CBs, and the cause of quality difference might be due to the difference of freezing conditions rather than the TWE effect.
脐带血（CB）库通常使用传统的程序降温冷冻机或自动BioArchive系统来冷冻和储存CB用于临床移植。本研究的目的是比较采用传统方法和自动方法冷冻保存的CB的质量，并明确两种方法之间质量差异的原因。该实验使用了80个CB样本：40个采用传统方法冷冻保存，其余的采用BioArchive系统冷冻保存。解冻后，比较了以下CB质量指标：细胞计数回收率、总核细胞（TNC）、单核细胞（MNC）和CD34+细胞的细胞活力，以及集落形成单位-粒细胞/巨噬细胞（CFU-GM）含量。此外，审查了处理和储存记录以量化CB样本在室温下的暴露次数（短暂升温事件，TWE），并分析其与CB质量的关系。MNC和CD34+细胞活力如下：MNC，78.2%±6.8%（传统方法），81.7%±7.2%（自动方法）；CD34+细胞，90.6%±6.9%（传统方法），94.7%±3.5%（自动方法）。每个CB样本的绝对CFU-GM含量在传统冷冻保存时为7.1×10±5.9×10，在自动冷冻保存时为12.3×10±12.0×10。采用BioArchive系统冷冻保存的CB显示出比传统冷冻保存的CB具有显著更高的MNC和CD34+细胞活力以及CFU-GM含量。根据TWE次数进行的CB质量比较显示，TWE暴露较多的组和暴露较少的组之间在质量上没有显著差异。采用BioArchive系统冷冻保存的CB质量高于传统冷冻保存的CB，质量差异的原因可能是冷冻条件的不同而非TWE效应。
