Adami V, Malangone W, Falasca E, Marini L, Risso A, Crini S, Toniutti E, Passoni Ferraro E, Del Frate G, Pittino M, Biffoni F, Rinaldi C, Degrassi A
Consorzio Fenice, University of Udine, Italy.
Blood Cells Mol Dis. 2005 Nov-Dec;35(3):389-97. doi: 10.1016/j.bcmd.2005.07.008. Epub 2005 Aug 19.
Umbilical cord blood (UCB) is a source of hematopoietic progenitor cells and is used as an alternative to the bone marrow or peripheral blood for treatment of several onco-hematological diseases. Because of the limited number of CD34+ hematopoietic stem cells present in UCB units and of the elevated costs of cryopreservation, it is of paramount importance to select the UCB units that are clinically useful before storage and optimize banking efficiency by designing reliable procedures to process and freeze the selected units. Among the different parameters characterizing UCB, nucleated cell (NC) and CD34+ cell content provides useful criteria to select UCB units since clinical data documented that the infused cell load (both NC and CD34+ cells) plays an important role in the successful outcome of transplants. By evaluating volume, CD34+ cell content, NC total amount, and NC density of 117 UCB units, we found a significant association between CD34+ cell content and NC density and total amount, indicating these parameters as useful to decide UCB clinical utility. Furthermore, we set up a fast procedure to process UCB units for storage. A system for NC separation and volume reduction of UCB samples in a dedicated, germ-free, closed circuit was developed, where plasma and red blood cells (RBC) depletion was obtained by sedimentation in the presence of a 3.5% Polygeline solution. By this separation system, both RBC depletion and high NC and CD34+ cell recoveries were achieved in 60 min, and the yield was comparable to the one obtained by other separation methods. Since Polygeline has been clinically used as a plasma expander and no toxic effects on patients were reported, the protocol can be applied in the large-scale banking of UCB.
脐带血（UCB）是造血祖细胞的一个来源，被用作治疗多种血液肿瘤疾病的骨髓或外周血的替代物。由于脐带血单位中存在的CD34+造血干细胞数量有限以及冷冻保存成本高昂，在储存前选择具有临床实用性的脐带血单位并通过设计可靠的程序来处理和冷冻所选单位以优化储存效率至关重要。在表征脐带血的不同参数中，有核细胞（NC）和CD34+细胞含量为选择脐带血单位提供了有用的标准，因为临床数据表明输入的细胞负荷（NC和CD34+细胞）在移植的成功结果中起着重要作用。通过评估117个脐带血单位的体积、CD34+细胞含量、NC总量和NC密度，我们发现CD34+细胞含量与NC密度和总量之间存在显著关联，表明这些参数有助于确定脐带血的临床实用性。此外，我们建立了一种快速处理脐带血单位以供储存的程序。开发了一种在专用的无菌封闭回路中进行脐带血样本NC分离和体积减少的系统，其中通过在3.5%聚明胶溶液存在下沉淀来实现血浆和红细胞（RBC）的去除。通过该分离系统，在60分钟内实现了RBC去除以及高NC和CD34+细胞回收率，并且产量与通过其他分离方法获得的产量相当。由于聚明胶已在临床上用作血浆扩容剂且未报告对患者有任何毒性作用，该方案可应用于脐带血的大规模储存。
