Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708-0281, USA.
Tissue Eng Part A. 2009 Nov;15(11):3575-87. doi: 10.1089/ten.TEA.2008.0444.
Endothelial progenitor cells isolated from umbilical cord blood (CB-EPCs) represent a promising source of endothelial cells for synthetic vascular grafts and tissue-engineered blood vessels since they are readily attainable, can be easily isolated, and possess a high proliferation potential. The objective of this study was to compare the functional behavior of late outgrowth CB-EPCs with human aortic endothelial cells (HAECs). CB-EPCs and HAECs were cultured on either smooth muscle cells in a coculture model of a tissue-engineered blood vessels or fibronectin adsorbed to Teflon-AF-coated glass slides. Late outgrowth CB-EPCs expressed endothelial cell-specific markers and were negative for the monocytic marker CD14. CB-EPCs have higher proliferation rates than HAECs, but are slightly smaller in size. CB-EPCs remained adherent under supraphysiological shear stresses, oriented and elongated in the direction of flow, and expressed similar numbers of alpha(5)beta(1) and alpha(v)beta(3) integrins and antithrombotic genes compared to HAECs. There were some differences in mRNA levels of E-selectin and vascular cell adhesion molecule 1 between CB-EPCs and HAECs; however, protein levels were similar on the two cell types, and CB-EPCs did not support adhesion of monocytes in the absence of tumor necrosis factor-alpha stimulation. Although CB-EPCs expressed significantly less endothelial nitric oxide synthase protein after exposure to flow than HAECs, nitric oxide levels induced by flow were not significantly different. These results suggest that late outgrowth CB-EPCs are functionally similar to HAECs under flow conditions and are a promising cell source for cardiovascular therapies.
从脐带血中分离出来的内皮祖细胞（CB-EPCs）是一种很有前途的合成血管移植物和组织工程血管内皮细胞的来源，因为它们很容易获得、易于分离，并且具有很高的增殖潜力。本研究的目的是比较晚期生长的 CB-EPCs 与人类主动脉内皮细胞（HAECs）的功能行为。CB-EPCs 和 HAECs 分别在平滑肌细胞共培养的组织工程血管模型或纤维连接蛋白吸附到特氟隆-AF 涂层玻片上进行培养。晚期生长的 CB-EPCs 表达内皮细胞特异性标志物，并且不表达单核细胞标志物 CD14。CB-EPCs 的增殖率高于 HAECs，但体积略小。CB-EPCs 在超生理剪切力下仍保持附着，沿流动方向定向伸长，并表达相似数量的α(5)β(1)和α(v)β(3)整合素和抗血栓基因，与 HAECs 相似。CB-EPCs 和 HAECs 之间的 E-选择素和血管细胞黏附分子 1 的 mRNA 水平存在一些差异；然而，两种细胞类型的蛋白水平相似，CB-EPCs 在没有肿瘤坏死因子-α刺激的情况下不支持单核细胞的黏附。尽管暴露于流动条件下的 CB-EPCs 表达的内皮型一氧化氮合酶蛋白明显少于 HAECs，但流动诱导的一氧化氮水平没有显著差异。这些结果表明，晚期生长的 CB-EPCs 在流动条件下的功能与 HAECs 相似，是心血管治疗的一种有前途的细胞来源。
