Sivarapatna Amogh, Ghaedi Mahboobe, Le Andrew V, Mendez Julio J, Qyang Yibing, Niklason Laura E
Department of Anesthesiology, Yale University, New Haven, CT 06519, USA; Department Biomedical Engineering, Yale University, New Haven, CT 06519, USA.
Department of Medicine, Section of Cardiovascular Medicine, Yale University, New Haven, CT 06519, USA.
Biomaterials. 2015;53:621-33. doi: 10.1016/j.biomaterials.2015.02.121. Epub 2015 Mar 24.
Endothelial cells (ECs) exist in different microenvironments in vivo, including under different levels of shear stress in arteries versus veins. Standard stem cell differentiation protocols to derive ECs and EC-subtypes from human induced pluripotent stem cells (hiPSCs) generally use growth factors or other soluble factors in an effort to specify cell fate. In this study, a biomimetic flow bioreactor was used to subject hiPSC-derived ECs (hiPSC-ECs) to shear stress to determine the impacts on phenotype and upregulation of markers associated with an anti-thrombotic, anti-inflammatory, arterial-like phenotype. The in vitro bioreactor system was able to efficiently mature hiPSC-ECs into arterial-like cells in 24 h, as demonstrated by qRT-PCR for arterial markers EphrinB2, CXCR4, Conexin40 and Notch1, as well protein-level expression of Notch1 intracellular domain (NICD). Furthermore, the exogenous addition of soluble factors was not able to fully recapitulate this phenotype that was imparted by shear stress exposure. The induction of these phenotypic changes was biomechanically mediated in the shear stress bioreactor. This biomimetic flow bioreactor is an effective means for the differentiation of hiPSC-ECs toward an arterial-like phenotype, and is amenable to scale-up for culturing large quantities of cells for tissue engineering applications.
内皮细胞（ECs）在体内存在于不同的微环境中，包括动脉与静脉中不同水平的剪切应力环境下。从人诱导多能干细胞（hiPSCs）中衍生出ECs和EC亚型的标准干细胞分化方案通常使用生长因子或其他可溶性因子来确定细胞命运。在本研究中，使用了一种仿生流动生物反应器，使hiPSC衍生的ECs（hiPSC-ECs）受到剪切应力作用，以确定其对表型以及与抗血栓、抗炎、动脉样表型相关标志物上调的影响。体外生物反应器系统能够在24小时内有效地将hiPSC-ECs成熟为动脉样细胞，这通过对动脉标志物EphrinB2、CXCR4、连接蛋白40和Notch1的qRT-PCR以及Notch1细胞内结构域（NICD）的蛋白质水平表达得以证明。此外，可溶性因子的外源添加无法完全重现由剪切应力暴露赋予的这种表型。这些表型变化的诱导是在剪切应力生物反应器中通过生物力学介导的。这种仿生流动生物反应器是使hiPSC-ECs向动脉样表型分化的有效手段，并且适合扩大规模以培养大量细胞用于组织工程应用。
