Rapid Manufacturing Engineering Center, Shanghai University , Shanghai 200444, People's Republic of China.
Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University , Shanghai 200072, People's Republic of China.
ACS Appl Mater Interfaces. 2016 Sep 28;8(38):25096-103. doi: 10.1021/acsami.6b07725. Epub 2016 Sep 16.
Despite considerable advances in tissue engineering over the past two decades, solutions to some crucial problems remain elusive. Vascularization is one of the most important factors that greatly influence the function of scaffolds. Many research studies have focused on the construction of a vascular-like network with prevascularization structure. Sacrificial materials are widely used to build perfusable vascular-like architectures, but most of these fabricated scaffolds only have a 2D plane-connected network. The fabrication of three-dimensional perfusable branched networks remains an urgent issue. In this work, we developed a novel sacrificial molding technique for fabricating biocompatible scaffolds with a three-dimensional perfusable branched network. Here, 3D-printed poly(vinyl alcohol) (PVA) filament was used as the sacrificial material. The fused PVA was deposited on the surface of a cylinder to create the 3D branched solid network. Gelatin was used to embed the solid network. Then, the PVA mold was dissolved after curing the hydrogel. The obtained architecture shows good perfusability. Cell experiment results indicated that human umbilical vein endothelial cells (HUVECs) successfully attached to the surface of the branched channel and maintained high viability after a few days in culture. In order to prevent deformation of the channel, paraffin was coated on the surface of the printed structure, and hydroxyapatite (HA) was added to gelatin. In conclusion, we demonstrate a novel strategy toward the engineering of prevasculature thick tissues through the integration of the fused PVA filament deposit. This approach has great potential in solving the issue of three-dimensional perfusable branched networks and opens the way to clinical applications.
尽管在过去的二十年中组织工程取得了相当大的进展，但一些关键问题的解决方案仍然难以捉摸。血管化是影响支架功能的最重要因素之一。许多研究都集中在构建具有预先血管化结构的类似血管的网络上。牺牲材料被广泛用于构建可灌注的类似血管的结构，但大多数这些制造的支架仅具有 2D 平面连接网络。制造三维可灌注分支网络仍然是一个紧迫的问题。在这项工作中，我们开发了一种新的牺牲模塑技术，用于制造具有三维可灌注分支网络的生物相容性支架。在这里，3D 打印的聚乙烯醇（PVA）纤维用作牺牲材料。熔融的 PVA 沉积在圆柱体的表面上以形成 3D 分支固体网络。明胶用于嵌入固体网络。然后，在水凝胶固化后溶解 PVA 模具。所获得的结构显示出良好的可灌注性。细胞实验结果表明，人脐静脉内皮细胞（HUVEC）在培养几天后成功附着在分支通道的表面上，并且保持高活力。为了防止通道变形，在打印结构的表面涂覆石蜡，并在明胶中添加羟基磷灰石（HA）。总之，我们通过融合 PVA 纤维沉积展示了一种用于预先血管化厚组织工程的新策略。该方法在解决三维可灌注分支网络问题方面具有很大的潜力，并为临床应用开辟了道路。
