The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen, 361005, China.
Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, 909 S Wolcott Ave, Chicago, IL, 60612, United States.
Small. 2022 Sep;18(36):e2202196. doi: 10.1002/smll.202202196. Epub 2022 Aug 16.
4D bioprinting techniques that facilitate formation of shape-changing scaffold-free cell condensates with prescribed geometries have yet been demonstrated. Here, a simple 4D bioprinting approach is presented that enables formation of a shape-morphing cell condensate-laden bilayer system. The strategy produces scaffold-free cell condensates which morph over time into predefined complex shapes. Cell condensate-laden bilayers with specific geometries are readily fabricated by bioprinting technologies. The bilayers have tunable deformability and microgel (MG) degradation, enabling controllable morphological transformations and on-demand liberation of deformed cell condensates. With this system, large cell condensate-laden constructs with various complex shapes are obtained. As a proof-of-concept study, the formation of the letter "C"- and helix-shaped robust cartilage-like tissues differentiated from human mesenchymal stem cells (hMSCs) is demonstrated. This system brings about a versatile 4D bioprinting platform idea that is anticipated to broaden and facilitate the applications of cell condensation-based 4D bioprinting.
目前已经展示了一些 4D 生物打印技术，这些技术可以方便地形成具有预定几何形状的、无需支架的形状变化的细胞凝聚体。在这里，我们提出了一种简单的 4D 生物打印方法，能够形成一种形状可变形的细胞凝聚体负载双层系统。该策略产生了无支架的细胞凝聚体，这些凝聚体随着时间的推移逐渐变成预先定义的复杂形状。通过生物打印技术可以很容易地制造出具有特定几何形状的细胞凝聚体负载双层。双层具有可调节的变形能力和微凝胶 (MG) 降解能力，能够实现可控的形态转变和按需释放变形的细胞凝聚体。利用该系统，获得了具有各种复杂形状的大型细胞凝聚体负载结构。作为概念验证研究，展示了由人间充质干细胞（hMSCs）分化而来的字母“C”形和螺旋形坚固软骨样组织的形成。该系统提出了一种通用的 4D 生物打印平台理念，有望拓宽和促进基于细胞凝聚的 4D 生物打印的应用。
