Laboratory of Bioregenerative Medicine & Surgery, Department of Surgery, Division of Plastic Surgery, Weill Cornell Medical College, New York, NY, USA.
Department of Breast Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.
Cartilage. 2021 Dec;13(2_suppl):1780S-1789S. doi: 10.1177/19476035211049556. Epub 2021 Oct 12.
A major obstacle in the clinical translation of engineered auricular scaffolds is the significant contraction and loss of topography that occur during maturation of the soft collagen-chondrocyte matrix into elastic cartilage. We hypothesized that 3-dimensional-printed, biocompatible scaffolds would "protect" maturing hydrogel constructs from contraction and loss of topography.
External disc-shaped and "ridged" scaffolds were designed and 3D-printed using polylactic acid (PLA). Acellular type I collagen constructs were cultured for up to 3 months. Collagen constructs seeded with bovine auricular chondrocytes (BAuCs) were prepared in 3 groups and implanted subcutaneously for 3 months: preformed discs with ("Scaffolded/S") or without ("Naked/N") an external scaffold and discs that were formed within an external scaffold via injection molding ("Injection Molded/SInj").
The presence of an external scaffold or use of injection molding methodology did not affect the acellular construct volume or base area loss. , the presence of an external scaffold significantly improved preservation of volume and base area at 3 months compared to the naked group ( < 0.05). Construct contraction was mitigated even further in the injection molded group, and topography of the ridged constructs was maintained with greater fidelity ( < 0.05). Histology verified the development of mature auricular cartilage in the constructs within external scaffolds after 3 months.
Custom-designed, 3D-printed, biocompatible external scaffolds significantly mitigate BAuC-seeded construct contraction and maintain complex topography. Further refinement and scaling of this approach in conjunction with construct fabrication utilizing injection molding may aid in the development of full-scale auricular scaffolds.
在工程化耳廓支架的临床转化中，一个主要障碍是在软胶原蛋白-软骨细胞基质成熟为弹性软骨的过程中，会发生显著的收缩和形貌损失。我们假设 3D 打印的生物相容性支架将“保护”成熟水凝胶结构免受收缩和形貌损失。
使用聚乳酸（PLA）设计并 3D 打印了外盘状和“脊状”支架。培养细胞外 I 型胶原构建体长达 3 个月。将牛耳软骨细胞（BAuC）接种的胶原构建体分为 3 组，皮下植入 3 个月：具有（“有支架/S”）或不具有（“无支架/N”）外部支架的预制盘，以及通过注塑成型在外部支架内形成的盘（“注塑成型/SInj”）。
外部支架的存在或使用注塑成型方法并不影响无细胞构建体的体积或基底面积损失。然而，与裸组相比，外部支架的存在显著改善了 3 个月时的体积和基底面积保留（<0.05）。即使在注塑成型组中，构建体的收缩也得到了进一步缓解，并且脊状构建体的形貌得到了更精确的保留（<0.05）。组织学验证了在外部支架内的构建体中 3 个月后成熟耳廓软骨的发育。
定制设计、3D 打印、生物相容性的外部支架可显著减轻 BAuC 接种构建体的收缩并保持复杂的形貌。与利用注塑成型进行构建体制造相结合，进一步改进和扩展这种方法可能有助于开发全尺寸耳廓支架。
