Shi Yang, Wang Fanlu, Tiwari Sanjay, Yesilbas Meran, Steubesand Nadine, Weitkamp Jan-Tobias, Klüter Tim, Lippross Sebastian, Eglin David, Seekamp Andreas, Fuchs Sabine
Experimental Trauma Surgery, Arnold-Heller-Straße 3, University Medical Center Schleswig-Holstein, UKSH, 24105, Kiel, Germany.
Molecular Imaging North Competence Center (MOINCC), Kiel, Germany.
J Orthop Res. 2016 Nov;34(11):1922-1932. doi: 10.1002/jor.23222. Epub 2016 Mar 14.
Engineering of a vascularized bone construct is a highly challenging task which needs to take into account the impact of different components on the bone regeneration process. Bone repair influencing factors in such constructs range from the material properties and scaffold design, to the interaction of different cell types contributing to bone formation and remodeling or neovascularization, respectively. In this context, early endothelial progenitor cells (EPC), mononuclear cells isolated from the peripheral blood, express the endothelial marker CD31 but also a series of myeloid markers and have been shown to support the formation of vessel-like structures. These cells are also characterized by a highly adaptable phenotype influenced by other cells creating an instructive niche. The present study was designed to investigate the impact of EPC on bone formation or remodeling using a co-culture system of outgrowth endothelial cells, mature endothelial cells isolated from the peripheral blood cell cultures, and mesenchymal stem cells grown on hydroxyapatite poly(ester-urethane) scaffolds. The formation of vessel-like structures in these constructs was shown by CLSM and immunohistochemistry and further evaluated by real time RT-PCR. Osteogenic differentiation in these constructs was investigated by von Kossa, Alizarin Red, and real time PCR. Data indicated that osteogenic differentiation occurred within the constructs after 14 days of culture but without a direct influence by EPC in this process. Finally, although we observed a series of osteoclast related makers in the constructs when EPC were included, no indications for an increased osteoclast-like activity, which might lead to increased bone resorption, were observed. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1922-1932, 2016.
构建带血管化的骨组织是一项极具挑战性的任务，需要考虑不同组件对骨再生过程的影响。此类构建物中影响骨修复的因素范围广泛，从材料特性和支架设计，到分别促成骨形成、重塑或新血管形成的不同细胞类型之间的相互作用。在这种情况下，早期内皮祖细胞（EPC），即从外周血中分离出的单核细胞，表达内皮标志物CD31，但也表达一系列髓系标志物，并且已被证明能支持血管样结构的形成。这些细胞还具有受其他细胞影响的高度适应性表型，这些细胞创造了一个具有指导作用的微环境。本研究旨在使用从外周血细胞培养物中分离出的迁出内皮细胞、成熟内皮细胞与在羟基磷灰石聚（酯 - 聚氨酯）支架上生长的间充质干细胞的共培养系统，研究EPC对骨形成或重塑的影响。通过共聚焦激光扫描显微镜（CLSM）和免疫组织化学显示了这些构建物中血管样结构的形成，并通过实时逆转录 - 聚合酶链反应（RT - PCR）进一步评估。通过冯·科萨染色、茜素红染色和实时聚合酶链反应（PCR）研究了这些构建物中的成骨分化。数据表明，培养14天后构建物内发生了成骨分化，但在此过程中EPC没有直接影响。最后，尽管当包含EPC时我们在构建物中观察到了一系列与破骨细胞相关的标志物，但未观察到破骨细胞样活性增加的迹象，而破骨细胞样活性增加可能导致骨吸收增加。©2016年矫形外科学研究协会。由威利期刊公司出版。《矫形外科学研究杂志》34:1922 - 1932，2016年。
