Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India.
Tissue Eng Part C Methods. 2012 Nov;18(11):890-902. doi: 10.1089/ten.TEC.2011.0482. Epub 2012 Oct 1.
Endothelial progenitor cells (EPCs) play a significant role in multiple biological processes such as vascular homeostasis, regeneration, and tumor angiogenesis. This makes them a promising cell of choice for studying a variety of biological processes, toxicity assays, biomaterial-cell interaction studies, as well as in tissue-engineering applications. In this study, we report the generation of two clones of SV40-immortalized EPCs from umbilical cord blood. These cells retained most of the functional features of mature endothelial cells and showed no indication of senescence after repeated culture for more than 240 days. Extensive functional characterization of the immortalized cells by western blot, flow cytometry, and immunofluorescence studies substantiated that these cells retained their ability to synthesize nitric oxide, von Willebrand factor, P-Selectin etc. These cells achieved unlimited proliferation potential subsequent to inactivation of the cyclin-dependent kinase inhibitor p21, but failed to form colonies on soft agar. We also show their enhanced growth and survival on vascular biomaterials compared to parental cultures in late population doubling. These immortalized EPCs can be used as a cellular model system for studying the biology of these cells, gene manipulation experiments, cell-biomaterial interactions, as well as a variety of tissue-engineering applications.
内皮祖细胞（EPCs）在多种生物学过程中发挥着重要作用，如血管稳态、再生和肿瘤血管生成。这使得它们成为研究多种生物学过程、毒性测定、生物材料-细胞相互作用研究以及组织工程应用的有前途的细胞选择。在这项研究中，我们报告了从脐带血中生成的两个 SV40 永生化 EPC 克隆。这些细胞保留了成熟内皮细胞的大部分功能特征，并且在重复培养超过 240 天后没有衰老的迹象。通过 Western blot、流式细胞术和免疫荧光研究对永生化细胞进行了广泛的功能表征，证实这些细胞保留了合成一氧化氮、血管性血友病因子、P 选择素等的能力。这些细胞在细胞周期依赖性激酶抑制剂 p21 失活后获得了无限增殖的潜力，但未能在软琼脂上形成菌落。我们还表明，与亲本培养物相比，它们在晚期群体倍增时在血管生物材料上的生长和存活得到了增强。这些永生化的 EPC 可用于研究这些细胞的生物学、基因操作实验、细胞-生物材料相互作用以及各种组织工程应用的细胞模型系统。
