Engineering Complex Anisotropic Scaffolds beyond Simply Uniaxial Alignment for Tissue Engineering

• Published in: Advanced functional materials 2022-04, Vol.32 (15), p.n/a
• Main Authors: Xing, Jiyao, Liu, Ning, Xu, Nannan, Chen, Wujun, Xing, Dongming
• Format: Article
• Language: English
• Subjects: 3D printing; Alignment; Bioengineering; complex anisotropy; Computer architecture; Materials science; modular assembly; Modular construction; Muscles; Scaffolds; Three dimensional printing; Tissue engineering
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202110676

Anisotropic microarchitectures arising from an aligned organization of threadlike extracellular matrix (ECM) components or cells are ubiquitous in the human body, such as skeletal muscle, corneal stroma, and meniscus, for executing tissue‐specific physiological functions. It is widely recognized that tissue engineering, whereby growing the implanted or endogenous cells in anisotropic scaffolds with geometrical resemblance to the ECM of targeted tissues, represents a promising solution for the structural and functional restoration of these anisotropic tissues. However, remarkable challenges remain in recapitulating the anisotropic complexities of native tissues beyond simply uniaxial alignment. Through unremitting endeavors over the past decade, some innovative bioengineering approaches are developed to tackle these challenges. This review focuses on the recent progress in modular assembly and 3D printing techniques exploited to construct complex anisotropic scaffolds with a key highlight on their accessibility and features for different types of anisotropies, based on understanding the whole picture of anisotropies beyond simply uniaxial alignment in native tissues, which are geometrically divided into three categories. Finally, the applications of these complex scaffolds in anisotropic tissue engineering, either in vitro modeling or in vivo regeneration, are explored. Complex anisotropic microarchitectures are ubiquitous in the human body for executing tissue‐specific physiological functions. This review outlines modular assembly and 3D printing techniques developed to construct complex anisotropic scaffolds, presenting a new classification of the tissue anisotropies, highlighting their accessibility and features for different types of anisotropies, and summarizing their applications in anisotropic tissue engineering.