Bolander J, Ji W, Geris L, Bloemen V, Chai Y C, Schrooten J, Luyten F P
Skeletal Biology and Engineering Research Center, O&N I Herestraat 49 - box 7003 13, 3000 Leuven,
Eur Cell Mater. 2016 Jan 5;31:11-25. doi: 10.22203/ecm.v031a02.
When combining osteogenic progenitor cells such as human periosteum derived cells (hPDCs) with osteoconductive biomaterials like calcium phosphate (CaP)-scaffolds, in vivo bone formation can be achieved. This process is dependent on the early activation of Bone morphogenetic protein (BMP)-signalling. However, the bone forming process is slow and routinely only a limited amount of bone and bone marrow is formed. Therefore, we hypothesised that a robust clinically relevant outcome could be achieved by adding more physiological levels of potent BMP-ligands to these cell- and CaP-based constructs. For this, hPDCs were characterised for their responsiveness to BMP-ligands upon in vitro 2D stimulation. BMP-2, -4, -6 and -9 robustly induced osteochondrogenic differentiation. Subsequently, these ligands were coated onto clinically approved CaP-scaffolds, BioOss® and CopiOs®, followed by hPDC-seeding. Protein lysates and conditioned media were investigated for activation of BMP signalling pathways. Upon in vivo implantation, the most abundant bone formation was found in BMP-2 and BMP-6-coated scaffolds. Implanted cells actively contributed to the newly formed bone. Remnants of cartilage could be observed in BMP-coated CopiOs®-constructs. Computational analysis displayed that the type of BMP-ligand as well as the CaP-scaffold affects skeletal tissue formation, observed in a qualitative as well as quantitative manner. Furthermore, the in vitro mechanism appears to predict the in vivo outcome. This study presents further evidence for the potential of BMP-technology in the development of clinically relevant cell-based constructs for bone regenerative strategies.
当将诸如人骨膜来源细胞（hPDCs）等成骨祖细胞与磷酸钙（CaP）支架等骨传导生物材料相结合时，可在体内实现骨形成。这一过程依赖于骨形态发生蛋白（BMP）信号的早期激活。然而，骨形成过程缓慢，通常仅形成有限量的骨和骨髓。因此，我们假设通过向这些基于细胞和CaP的构建体中添加更接近生理水平的强效BMP配体，可以实现强大的临床相关结果。为此，对hPDCs在体外二维刺激下对BMP配体的反应性进行了表征。BMP-2、-4、-6和-9强烈诱导骨软骨分化。随后，将这些配体包被在临床批准的CaP支架BioOss®和CopiOs®上，然后接种hPDCs。对蛋白质裂解物和条件培养基进行研究，以检测BMP信号通路的激活情况。在体内植入后，在包被BMP-2和BMP-6的支架中发现了最丰富的骨形成。植入的细胞积极参与了新形成的骨。在包被BMP的CopiOs®构建体中可观察到软骨残留。计算分析表明，BMP配体的类型以及CaP支架以定性和定量方式影响骨骼组织的形成。此外，体外机制似乎可以预测体内结果。本研究为BMP技术在开发用于骨再生策略的临床相关基于细胞的构建体方面的潜力提供了进一步的证据。
