Tissue engineering technology provides a promising approach for external ear reconstruction. Although the first clinical breakthrough of tissue engineered auricular reconstruction has been achieved based on polymer scaffold, the discrepant clinical efficacy among different patients triggered by residual scaffold mediated aseptic inflammatory reaction seriously hinders its further clinical application. A proper natural scaffold with low inflammatory reaction is urgently required to address this problem. Among all the natural materials, acellular cartilage matrix (ACM) is considered to be the ideal cartilage-specific microenvironmental biomimetic scaffold. However, no breakthroughs have been achieved for the regeneration of human-ear-shaped cartilage based on ACM so far. The main challenge is how to prepare ACM into a three-dimensional (3D) porous scaffold with precise human-ear shape and proper mechanical strength. In this study, ACM powder, prepared by freezing pulverization and decellularization, was successfully prepared into 3D porous scaffolds using gelatin as an auxiliary crosslinker. By optimizing proportion and concentration of ACM and gelatin, the scaffolds presented proper pore structure and degradation rate as well as good mechanical strength and biocompatibility. Furthermore, ACM/Gelatin could be fabricated into porous scaffolds with precise human-ear shape and proper mechanical strength by integrating 3D printing, polycaprolactone (PCL) inner core designing, cast molding, and freeze-drying technologies. Finally, human-ear-shaped cartilage with good elasticity and cartilage-specific extracellular matrices was successfully regenerated using the ACM/Gelatin-PCL scaffolds and auricular chondrocytes (elastic cartilage). All of these results provide important support for the application and clinical translation of human-ear-shaped cartilage.

组织工程技术为外耳重建提供了一种有前途的方法。尽管基于聚合物支架实现了组织工程性耳廓重建的第一个临床突破，但是由残余支架介导的无菌性炎症反应触发的不同患者之间的差异性临床疗效严重阻碍了其进一步的临床应用。迫切需要具有低炎症反应的合适的天然支架来解决该问题。在所有天然材料中，无细胞软骨基质（ACM）被认为是理想的软骨特异性微环境仿生支架。然而，到目前为止，基于ACM的人耳形软骨再生还没有突破。主要挑战是如何将ACM制成具有精确的人耳形状和适当的机械强度的三维（3D）多孔支架。在这项研究中，通过使用明胶作为辅助交联剂，将通过冷冻粉碎和脱细胞制备的ACM粉末成功制备为3D多孔支架。通过优化ACM和明胶的比例和浓度，该支架具有合适的孔结构和降解速率，并具有良好的机械强度和生物相容性。此外，通过整合3D打印，聚己内酯（PCL）内芯设计，浇铸成型和冷冻干燥技术，可以将ACM /明胶制成具有精确人耳形状和适当机械强度的多孔支架。最后，使用ACM /明胶-PCL支架和耳软骨细胞（弹性软骨）成功地再生了具有良好弹性的人耳形软骨和特定于软骨的细胞外基质。所有这些结果为人耳形软骨的应用和临床翻译提供了重要的支持。