Direct 3D bioprinting of cardiac micro-tissues mimicking native myocardium
Direct 3D bioprinting of cardiac micro-tissues mimicking native myocardium
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DOI：
10.1016/j.biomaterials.2020.120204
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发表时间：
2020-10-01
期刊：
影响因子：
14
通讯作者：
Chen, Shaochen
中科院分区：
文献类型：
--
作者：
Liu, Justin;Miller, Kathleen;Chen, Shaochen
心脏拥有复杂的三维（3D）层状肌纤维组织；但是，由于工程与生理相关的3D组织仍然是一项技术挑战，因此尚未系统地研究心肌细胞对齐对激发量耦合，缩短和力发育的影响。 3D中的细胞形状和方向可以通过工程脚手架微观结构并封装在这些几何提示附近的细胞来控制。 Here, we show that a novel method of cell encapsulation in 3D methacrylated gelatin (GelMA) scaffolds patterned via Microscale Continuous Optical Printing (mu COP) can rapidly micropattern neonatal mouse ventricular cardiomyocytes (NMVCMs) in photocrosslinkable hydrogels.封装的心肌细胞优先与工程的微体系结构保持一致，并可以在体内显示心肌的形态和肌原纤维比对表型。使用MU COP系统，直接印刷了一种不对称的，多物质的基于悬臂的支架，因此微动物产生的力被传输到单个可变形支柱上。与对齐的2D种子样品相比，对齐的3D封装NMVCM支架产生了近2倍。为了进一步强调MU COP的灵活性，以几种模式封装了NMVCM，以比较不同程度比对对组织位移和同步性的影响。良好的肌化培养模式对齐的培养模式产生了4-10倍的收缩力，这些收缩力较少。最后，NMVCM封装的结构的归一化氟-4荧光显示出特征性的钙瞬态波形，在用100 nm异丙肾上腺素治疗期间的幅度和下降速率增加。这款新型的仪器3D心脏微动物是一种在生理上相关的体外模型系统，具有巨大的心脏病建模和药物筛查潜力。
The heart possesses a complex three-dimensional (3D) laminar myofiber organization; however, because engineering physiologically relevant 3D tissues remains a technical challenge, the effects of cardiomyocyte alignment on excitation-contraction coupling, shortening and force development have not been systematically studied. Cellular shape and orientations in 3D can be controlled by engineering scaffold microstructures and encapsulating cells near these geometric cues. Here, we show that a novel method of cell encapsulation in 3D methacrylated gelatin (GelMA) scaffolds patterned via Microscale Continuous Optical Printing (mu COP) can rapidly micropattern neonatal mouse ventricular cardiomyocytes (NMVCMs) in photocrosslinkable hydrogels. Encapsulated cardiomyocytes preferentially align with the engineered microarchitecture and can display morphology and myofibril alignment phenotypic of myocardium in vivo. Utilizing the mu COP system, an asymmetric, multi-material, cantilever-based scaffold was directly printed, so that the force produced by the microtissue was transmitted onto a single deformable pillar. Aligned 3D encapsulated NMVCM scaffolds produced nearly 2 times the force compared to aligned 2D seeded samples. To further highlight the flexibility of mu COP, NMVCMs were encapsulated in several patterns to compare the effects of varying degrees of alignment on tissue displacement and synchronicity. Well aligned myofiber cultured patterns generated 4-10 times the contractile force of less anisotropically patterned constructs. Finally, normalized fluo-4 fluorescence of NMVCM-encapsulated structures showed characteristic calcium transient waveforms that increased in magnitude and rate of decline during treatment with 100 nM isoproterenol. This novel instrumented 3D cardiac microtissue serves as a physiologically relevant in vitro model system with great potential for use in cardiac disease modeling and drug screening.