School of Biological and Health Systems Engineering, Arizona State University.
School of Biological and Health Systems Engineering, Arizona State University; Biodesign Virginia G. Piper Center for Personalized Diagnostics, Arizona State University;
J Vis Exp. 2021 Jun 15(172). doi: 10.3791/62539.
The leading cause of death worldwide persists as cardiovascular disease (CVD). However, modeling the physiological and biological complexity of the heart muscle, the myocardium, is notoriously difficult to accomplish in vitro. Mainly, obstacles lie in the need for human cardiomyocytes (CMs) that are either adult or exhibit adult-like phenotypes and can successfully replicate the myocardium's cellular complexity and intricate 3D architecture. Unfortunately, due to ethical concerns and lack of available primary patient-derived human cardiac tissue, combined with the minimal proliferation of CMs, the sourcing of viable human CMs has been a limiting step for cardiac tissue engineering. To this end, most research has transitioned toward cardiac differentiation of human induced pluripotent stem cells (hiPSCs) as the primary source of human CMs, resulting in the wide incorporation of hiPSC-CMs within in vitro assays for cardiac tissue modeling. Here in this work, we demonstrate a protocol for developing a 3D mature stem cell-derived human cardiac tissue within a microfluidic device. We specifically explain and visually demonstrate the production of a 3D in vitro anisotropic cardiac tissue-on-a-chip model from hiPSC-derived CMs. We primarily describe a purification protocol to select for CMs, the co-culture of cells with a defined ratio via mixing CMs with human CFs (hCFs), and suspension of this co-culture within the collagen-based hydrogel. We further demonstrate the injection of the cell-laden hydrogel within our well-defined microfluidic device, embedded with staggered elliptical microposts that serve as surface topography to induce a high degree of alignment of the surrounding cells and the hydrogel matrix, mimicking the architecture of the native myocardium. We envision that the proposed 3D anisotropic cardiac tissue-on-chip model is suitable for fundamental biology studies, disease modeling, and, through its use as a screening tool, pharmaceutical testing.
全球范围内的主要死亡原因仍然是心血管疾病（CVD）。然而，对心肌这种心脏肌肉的生理和生物复杂性进行建模非常困难，这在体外是众所周知的。主要障碍在于需要具有成人或表现出成人样表型的人类心肌细胞（CM），并且能够成功复制心肌的细胞复杂性和复杂的 3D 结构。不幸的是，由于伦理问题和缺乏可用的原发性患者来源的人心肌组织，加上 CM 的增殖有限，因此获得可行的人类 CM 一直是心脏组织工程的一个限制步骤。为此，大多数研究已经转向人类诱导多能干细胞（hiPSC）的心脏分化作为人类 CM 的主要来源，从而使 hiPSC-CM 广泛纳入体外心脏组织建模的测定中。在此项工作中，我们展示了在微流控装置中开发成熟的 3D 干细胞衍生人心肌组织的方案。我们特别解释并直观地展示了从 hiPSC 衍生的 CM 产生 3D 体外各向异性心脏组织芯片模型的过程。我们主要描述了一种用于选择 CM 的纯化方案，通过将 CM 与人类成纤维细胞（hCF）以特定比例混合进行细胞共培养，以及将共培养物悬浮在基于胶原蛋白的水凝胶中。我们进一步展示了将细胞负载水凝胶注入我们定义明确的微流控装置中，该装置中嵌入了交错的椭圆形微柱，作为表面形貌，以诱导周围细胞和水凝胶基质的高度对齐，模拟天然心肌的结构。我们设想所提出的 3D 各向异性心脏组织芯片模型适合于基础生物学研究、疾病建模，并且通过将其用作筛选工具，还适合药物测试。
