Bone graft substitutes and bone void fillers are predominantly used to treat bone defects and bone fusion in orthopaedic surgery. Some aragonite-based scaffolds of coralline exoskeleton origin exhibit osteoconductive properties and are described as useful bone repair scaffolds. The purpose of this study was to evaluate the in vitro osteogenic potential of the bone phase of a novel aragonite-based bi-phasic osteochondral scaffold (Agili-C™, CartiHeal Ltd.) using adult human bone marrow-derived mesenchymal stem cells (MSCs). Analyses were performed at several time intervals: 3, 7, 14, 21, 28 and 42 days post-seeding. Osteogenic differentiation was assessed by morphological characterisation using light microscopy after Alizarin red and von Kossa staining, and scanning electron microscopy. The transcript levels of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), bone gamma-carboxyglutamate (BGLAP), osteonectin (SPARC) and osteopontin (SPP1) were determined by quantitative PCR. Proliferation was assessed by a thymidine incorporation assay and proliferating cell nuclear antigen (PCNA) immunocytochemistry. Our results demonstrate that the bone phase of the bi-phasic aragonite-based scaffold supports osteogenic differentiation and enhanced proliferation of bone marrow-derived MSCs at both the molecular and histological levels. The scaffold was colonized by differentiating MSCs, suggesting its suitability for incorporation into bone voids to accelerate bone healing, remodelling and regeneration. The mechanism of osteogenic differentiation involves scaffold surface modification with de novo production of calcium phosphate deposits, as revealed by energy dispersive spectroscopy (EDS) analyses. This novel coral-based scaffold may promote the rapid formation of high quality bone during the repair of osteochondral lesions.

骨移植替代物和骨空隙填充剂主要用于骨科手术中的骨缺损和骨融合。珊瑚外骨骼起源的一些基于文石的支架表现出骨传导特性，并被描述为有用的骨修复支架。这项研究的目的是评估体外一种新型的基于文石的双相骨软骨支架（Agili-C™，CartiHeal Ltd.）使用成年人类骨髓源性间充质干细胞（MSC）的骨相的成骨潜力。在几个时间间隔内进行分析：播种后3、7、14、21、28和42天。在茜素红和von Kossa染色后，使用光学显微镜通过形态学特征评估成骨分化，并通过扫描电子显微镜进行评估。碱性磷酸酶（ALP），矮子相关转录因子2（RUNX2），骨γ-羧基谷氨酸（BGLAP），骨连接素（SPARC）和骨桥蛋白（SPP1）的转录水平通过定量PCR确定。通过胸苷掺入试验和增殖细胞核抗原（PCNA）免疫细胞化学评估增殖。我们的研究结果表明，基于两相文石的支架的骨相在分子和组织学水平上均支持成骨分化并增强了骨髓来源的MSC的增殖。该支架通过分化MSC进行定殖，表明其适合掺入骨腔以加速骨愈合，重塑和再生。成骨分化的机制涉及从头进行支架表面修饰能量分散光谱（EDS）分析显示，磷酸钙沉积物的产生。这种新颖的基于珊瑚的支架可以在骨软骨损伤的修复过程中促进高质量骨骼的快速形成。