Zhai Qiong-li, Qiu Lu-gui, Li Qian, Zhou Yu, Yu Zhen, Meng Heng-xing, Han Jun-ling, Ying Hong-guang, Han Zhong-chao
Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, China.
Zhonghua Yi Xue Za Zhi. 2003 Jul 25;83(14):1262-5.
To study the effect of ex vivo expansion on the adhesion activities and chemotactic function of umbilical cord blood (UCB) hematopoietic stem and progenitor cells (HSPCs).
CD34(+) cells isolated from fresh UCB samples were cultured in serum-free and stroma-free culture system. After 7, 10 and 14 days' culture, CD34(+) cells were re-selected from the expanded products. Stromal cell- derived factor-1 (SDF-1) 100 ng/ml was added into the experimental CD34(+) cells and the absorbance at 570 nm of all groups was examined. 20 micro g/ml fibronectin (Fn) was added and the spontaneous adhesion between CD34(+) and FN was detected by MTT method. The homing-related functions including expression of homing-related adhesion molecules (CAM), adhesion activity and chemotactic function of the re-selected CD34(+) cells were evaluated and compared with those of the initial fresh CD34(+) cells.
(1) The expression of CD49d, CD44, CD11a and CD49e on expanded CD34(+) cells increased or sustained the same levels as those of the fresh isolated UCB CD34(+) cells, while the expression of CD62L, CD54 and CD31 on expanded CD34(+) cells declined during the culture. (2) The spontaneous adhesion between CD34(+) and FN and SDF-1-induced adhesion continuously increased in the course of the first 10-day culture. The spontaneous adhesion rate and SDF-1-induced adhesion rate on day 0, day 7 and day 10 were 28% and 63%, 60% and 70%, 63% and 90% respectively. (3) The migration efficiency of re-selected CD34(+) cells on day 7 was almost the same compared to that of fresh CD34(+) cells.
The expanded HSPCs sustain most of the homing-related characteristics and activities during one-week culture while extended culture may partly impair their intrinsic homing potential.
研究体外扩增对脐血造血干细胞和祖细胞（HSPCs）黏附活性及趋化功能的影响。
从新鲜脐血样本中分离出的CD34(+)细胞在无血清、无基质的培养体系中培养。培养7、10和14天后，从扩增产物中重新筛选出CD34(+)细胞。向实验性CD34(+)细胞中加入100 ng/ml基质细胞衍生因子-1（SDF-1），检测所有组在570 nm处的吸光度。加入20 μg/ml纤连蛋白（Fn），采用MTT法检测CD34(+)与Fn之间的自发黏附。评估重新筛选出的CD34(+)细胞的归巢相关功能，包括归巢相关黏附分子（CAM）的表达、黏附活性和趋化功能，并与初始新鲜CD34(+)细胞进行比较。
（1）扩增后的CD34(+)细胞上CD49d、CD44、CD11a和CD49e的表达增加或维持与新鲜分离的脐血CD34(+)细胞相同的水平，而扩增后的CD34(+)细胞上CD62L、CD54和CD31的表达在培养过程中下降。（2）在培养的前10天内，CD34(+)与Fn之间的自发黏附以及SDF-1诱导的黏附持续增加。第0天、第7天和第10天的自发黏附率和SDF-1诱导的黏附率分别为28%和63%、60%和70%、63%和90%。（3）第7天重新筛选出的CD34(+)细胞的迁移效率与新鲜CD34(+)细胞几乎相同。
扩增后的HSPCs在一周培养期间维持了大部分归巢相关特征和活性，而延长培养可能会部分损害其内在归巢潜能。
