Department of Veterinary Medicine, Institute of Veterinary Anatomy, Freie Universitaet Berlin, Koserstraße 20, 14195 Berlin, Germany.
Department of Veterinary Medicine, Institute of Veterinary Epidemiology and Biostatistics, Freie Universitaet Berlin, Koenigsweg 67, 14163 Berlin, Germany.
Int J Mol Sci. 2017 Dec 1;18(12):2590. doi: 10.3390/ijms18122590.
Increasing the complexity of in vitro systems to mimic three-dimensional tissues and the cellular interactions within them will increase the reliability of data that were previously collected with in vitro systems. In vivo vascularization is based on complex and clearly defined cell-matrix and cell-cell interactions, where the extracellular matrix (ECM) seems to play a very important role. The aim of this study was to monitor and visualize the subcellular and molecular interactions between endothelial cells (ECs), fibroblasts, and their surrounding microenvironment during vascular morphogenesis in a three-dimensional coculture model.
Quantitative and qualitative analyses during the generation of a coculture tissue construct consisting of endothelial cells and fibroblasts were done using transmission electron microscopy and immunohistochemistry.
Dynamic interactions were found in cocultures between ECs, between fibroblasts (FBs), between ECs and FBs, and between the cells and the ECM. Microvesicles were involved in intercellular information transfer. FBs took an active and physical part in the angiogenesis process. The ECM deposited by the cells triggered endothelial angiogenic activity. Capillary-like tubular structures developed and matured. Moreover, some ECM assembled into a basement membrane (BM) having three different layers equivalent to those seen in vivo. Finally, the three-dimensional in vitro construct mirrored the topography of histological tissue sections.
Our results visualize the importance of the physical contact between all cellular and acellular components of the cocultures.
增加体外系统的复杂性以模拟三维组织和其中的细胞相互作用将提高以前使用体外系统收集的数据的可靠性。体内血管生成基于复杂且明确定义的细胞-基质和细胞-细胞相互作用，其中细胞外基质（ECM）似乎起着非常重要的作用。本研究旨在监测和可视化在三维共培养模型中血管发生过程中内皮细胞（ECs）、成纤维细胞及其周围微环境之间的亚细胞和分子相互作用。
使用透射电子显微镜和免疫组织化学对由内皮细胞和成纤维细胞组成的共培养组织构建体的生成过程进行定量和定性分析。
在 ECs 之间、FBs 之间、ECs 和 FBs 之间以及细胞和 ECM 之间的共培养中发现了动态相互作用。微泡参与细胞间信息传递。FBs 在血管生成过程中发挥积极的物理作用。细胞分泌的 ECM 触发内皮血管生成活性。毛细血管样管状结构发育并成熟。此外，一些 ECM 组装成具有与体内所见相当的三层的基底膜（BM）。最后，三维体外构建体反映了组织学切片的拓扑结构。
我们的结果可视化了共培养中所有细胞和无细胞成分之间物理接触的重要性。
