Manipulation of Oxygenation and Flow-Induced Shear Stress Can Increase the In Vitro Yield of Platelets from Cord Blood
Manipulation of Oxygenation and Flow-Induced Shear Stress Can Increase the In Vitro Yield of Platelets from Cord Blood
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DOI：
10.1089/ten.tec.2011.0108
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发表时间：
2011-11-01
影响因子：
3
通讯作者：
Sullenbarger, Brent
中科院分区：
文献类型：
--
作者：
Lasky, Larry C.;Sullenbarger, Brent
一种在体外生产临床上有用的血小板的方法将有助于克服频繁的短缺、供体延期、疾病传播以及使用志愿者供体来源的血小板进行同种免疫的问题。使用 CD34 阳性选择的脐带血细胞，我们研究了在三维模块化灌注生物反应器系统中提高血小板质量和产量的方法。我们发现，仅当培养过程的早期阶段在 5% 氧气下进行时，与在整个培养期间使用 20% 氧气时相比，产生的血小板数量增加了两到三倍 (p < 0.05)，并且比在整个培养过程中使用 5% 氧气时要多得多。当培养基流过细胞支架结构时，与在结构下方和上方流动或仅使用间歇性补料相比，血小板数量增加了两到三倍（p < 0.05），并增强了胶原蛋白诱导的聚集。培养过程早期的 5% 氧气模拟了早期祖细胞增殖的骨骼附近的骨髓。通过细胞支架结构的流动产生模拟骨髓中央静脉窦流动的剪切力，并增强前血小板的血小板生成。使用改变的氧气水平和错流增强了血小板数量和质量，并将有助于最终用于临床的体外血小板生产。
A method to produce clinically useful platelets in vitro would help overcome the frequent shortages, donor deferrals, disease transmission, and alloimmunization with volunteer donor-derived platelets. Using CD34 positively selected cord blood cells, we investigated ways to increase platelet quality and yield in a three-dimensional modular perfusion bioreactor system. We found a two-to threefold increase in platelet numbers produced only when the early phases of the culture process were carried out at 5% oxygen, versus when 20% oxygen was used throughout the culture period (p < 0.05), and much more than when 5% oxygen was used throughout. When the medium was routed through the cell-scaffold construct, versus when it flowed under and over the construct, or just intermittent feeding was used, the number of platelets increased two-to threefold (p < 0.05), and enhanced collagen-induced aggregation. The 5% oxygen early in the culture process mimics the marrow adjacent to the bone where early progenitors proliferate. Flow through the cell-scaffold construct creates shear forces that mimic the flow in central venous sinuses of the marrow and enhances platelet production from proplatelets. The use of altered oxygen levels and cross flow enhanced platelet numbers and quality, and will contribute to eventual in vitro platelet production for clinical use.