Moser Caroline, Bardsley Katie, El Haj Alicia J, Alini Mauro, Stoddart Martin J, Bara Jennifer J
AO Research Institute Davos, Davos, Switzerland.
Laboratory for Translational Nutritional Biology, Department of Health Sciences and Technologies, Institute of Food Nutrition and Health, ETH Zürich, Zürich, Switzerland.
Front Bioeng Biotechnol. 2018 Nov 15;6:161. doi: 10.3389/fbioe.2018.00161. eCollection 2018.
Biomaterials development for bone repair is currently hindered by the lack of physiologically relevant testing systems. Here we describe the novel use of a bi-directional perfusion bioreactor to support the long term culture of human bone marrow stromal cells (BMSCs) differentiated on polylactic co-glycolic acid (PLGA). Primary human BMSCs were seeded onto porous PLGA scaffolds and cultured in static vs. perfusion culture conditions for 21 days in osteogenic vs. control media. PLGA scaffolds were osteoconductive, supporting a mature osteogenic phenotype as shown by the upregulation of Runx2 and the early osteocyte marker E11. Perfusion culture enhanced the expression of osteogenic genes Osteocalcin and Osteopontin. Extracellular matrix deposition and mineralisation were spatially regulated within PLGA scaffolds in a donor dependant manner. This, together with the observed upregulation of Collagen type X suggested an environment permissive for the study of differentiation pathways associated with both intramembranous and endochondral ossification routes of bone healing. This culture system offers a platform to assess BMSC behavior on candidate biomaterials under physiologically relevant conditions. Use of this system may improve our understanding of the environmental cues orchestrating BMSC differentiation and enable fine tuning of biomaterial design as we develop tissue-engineered strategies for bone regeneration.
目前，缺乏生理相关的测试系统阻碍了用于骨修复的生物材料的发展。在此，我们描述了一种双向灌注生物反应器的新用途，该反应器用于支持在聚乳酸 - 乙醇酸共聚物（PLGA）上分化的人骨髓基质细胞（BMSC）的长期培养。将原代人BMSC接种到多孔PLGA支架上，并在成骨培养基与对照培养基中，于静态与灌注培养条件下培养21天。PLGA支架具有骨传导性，支持成熟的成骨表型，如Runx2和早期骨细胞标志物E11的上调所示。灌注培养增强了成骨基因骨钙素和骨桥蛋白的表达。细胞外基质沉积和矿化在PLGA支架内以供体依赖的方式在空间上受到调节。这与观察到的X型胶原蛋白上调一起，提示了一个有利于研究与骨愈合的膜内和软骨内成骨途径相关的分化途径的环境。该培养系统提供了一个平台，用于在生理相关条件下评估BMSC在候选生物材料上的行为。使用该系统可能会增进我们对协调BMSC分化的环境线索的理解，并在我们开发骨再生的组织工程策略时，实现生物材料设计的微调。
