Kim Min Sung, Lee Byungjun, Kim Hong Nam, Bang Seokyoung, Yang Hee Seok, Kang Seong Min, Suh Kahp-Yang, Park Suk-Hee, Jeon Noo Li
School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, Republic of Korea.
Biofabrication. 2017 Mar 23;9(1):015029. doi: 10.1088/1758-5090/aa64a0.
We present a novel approach for assembling 3D tissue by layer-by-layer stacking of cell sheets formed on aligned nanofiber mesh. A rigid frame was used to repeatedly collect aligned electrospun PCL (polycaprolactone) nanofiber to form a mesh structure with average distance between fibers 6.4 µm. When human umbilical vein endothelial cells (HUVECs), human foreskin dermal fibroblasts, and skeletal muscle cells (C2C12) were cultured on the nanofiber mesh, they formed confluent monolayers and could be handled as continuous cell sheets with areas 3 × 3 cm or larger. Thicker 3D tissues have been formed by stacking multiple cell sheets collected on frames that can be nested (i.e. Matryoshka dolls) without any special tools. When cultured on the nanofiber mesh, skeletal muscle, C2C12 cells oriented along the direction of the nanofibers and differentiated into uniaxially aligned multinucleated myotube. Myotube cell sheets were stacked (upto 3 layers) in alternating or aligned directions to form thicker tissue with ∼50 µm thickness. Sandwiching HUVEC cell sheets with two dermal fibroblast cell sheets resulted in vascularized 3D tissue. HUVECs formed extensive networks and expressed CD31, a marker of endothelial cells. Cell sheets formed on nanofiber mesh have a number of advantages, including manipulation and stacking of multiple cell sheets for constructing 3D tissue and may find applications in a variety of tissue engineering applications.
我们提出了一种通过在排列好的纳米纤维网上逐层堆叠细胞片来组装三维组织的新方法。使用一个刚性框架反复收集排列好的电纺聚己内酯（PCL）纳米纤维，以形成纤维平均间距为6.4 µm的网状结构。当人脐静脉内皮细胞（HUVECs）、人包皮真皮成纤维细胞和骨骼肌细胞（C2C12）在纳米纤维网上培养时，它们形成汇合的单层细胞，并且可以作为面积为3×3 cm或更大的连续细胞片进行处理。通过堆叠收集在可嵌套（即俄罗斯套娃）框架上的多个细胞片，无需任何特殊工具即可形成更厚的三维组织。当在纳米纤维网上培养时，骨骼肌C2C12细胞沿纳米纤维方向排列，并分化为单轴排列的多核肌管。将肌管细胞片以交替或对齐的方向堆叠（最多3层），以形成厚度约为50 µm的更厚组织。用人真皮成纤维细胞片夹在中间的人脐静脉内皮细胞片形成了血管化的三维组织。人脐静脉内皮细胞形成了广泛的网络并表达了内皮细胞标志物CD31。在纳米纤维网上形成的细胞片具有许多优点，包括用于构建三维组织的多个细胞片的操作和堆叠，并且可能在各种组织工程应用中找到应用。
