Kang Jennifer H, Gimble Jeffrey M, Kaplan David L
Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA.
Tissue Eng Part A. 2009 Aug;15(8):2227-36. doi: 10.1089/ten.tea.2008.0469.
The clinical need for both three-dimensional (3D) soft tissue replacements and in vitro adipose tissue models continues to grow. In this study, we evaluated structural and functional characteristics of an in vitro 3D coculture model of vascularized adipose tissue. Tomato red-infected human adipose tissue-derived mesenchymal stem cells (hASCs) and green fluorescence protein-infected human umbilical vein endothelial cells were cocultured on 3D aqueous-derived silk scaffolds for 2 weeks. Confocal microscopy images demonstrated viability of cocultures and organization of both cell types over time. Endothelial cells aligned with time, and further histological analyses revealed continuous endothelial lumen formation in both differentiated and undifferentiated cocultures. Differentiated adipose cocultures secreted significantly higher levels of leptin than undifferentiated cocultures at 1 and 2 weeks. Additionally, lipid accumulation was demonstrated with Oil Red O staining, where positive staining was higher in the differentiated cocultures. A promising in vitro approach for the vascularization of tissue-engineered adipose tissue, and the ability to vascularize a construct containing hASCs was demonstrated. The strategy outlined provides a basis for the formation of other in vitro vascularized tissues as well as a path forward for the sustainable formation of soft tissue due to the use of slowly degrading silk scaffolds.
对三维（3D）软组织替代物和体外脂肪组织模型的临床需求持续增长。在本研究中，我们评估了血管化脂肪组织的体外3D共培养模型的结构和功能特征。将番茄红素感染的人脂肪组织来源的间充质干细胞（hASCs）和绿色荧光蛋白感染的人脐静脉内皮细胞在3D水衍生丝支架上共培养2周。共聚焦显微镜图像显示了共培养物的活力以及两种细胞类型随时间的组织情况。内皮细胞随时间排列，进一步的组织学分析显示在分化和未分化的共培养物中均有连续的内皮管腔形成。在第1周和第2周时，分化的脂肪共培养物分泌的瘦素水平明显高于未分化的共培养物。此外，用油红O染色显示有脂质积累，其中分化的共培养物中的阳性染色更高。证明了一种用于组织工程化脂肪组织血管化的有前景的体外方法，以及使含有hASCs的构建体血管化的能力。所概述的策略为其他体外血管化组织的形成提供了基础，也为由于使用缓慢降解的丝支架而实现软组织的可持续形成提供了一条前进的道路。
