In this study, we evaluated the use of graphene oxide (GO) mixed with methyl methacrylate gelatin (GelMA) for the construction of a microenvironmental implant to repair bone defects in orthopedic surgery. A scaffold containing a GelMA/GO composite with mesenchymal stem cells (MSCs) was constructed using three-dimensional bioprinting. The survival and osteogenic capacity of MSCs in the composite bioink were evaluated using cell viability and proliferation assays, osteogenesis-related gene expression analysis, and implantation under the skin of nude mice. The printing process had little effect on cell viability. We found that GO enhanced cell proliferation but had no significant effect on cell viability. In vitro experiments suggested that GO promoted material–cell interactions and the expression of osteogenesis-related genes. In vivo experiments showed that GO decreased the degradation time of the material and increased calcium nodule deposition. In contrast to pure GelMA, the addition of GO created a suitable microenvironment to promote the differentiation of loaded exogenous MSCs in vitro and in vivo, providing a basis for the repair of bone defects.

中文翻译：

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三维生物打印 GelMA/GO 复合水凝胶用于体外和体内干细胞成骨分化

在这项研究中，我们评估了使用氧化石墨烯（GO）与甲基丙烯酸甲酯明胶（GelMA）混合构建微环境植入物来修复骨科手术中的骨缺损。使用三维生物打印构建了包含 GelMA/GO 复合材料和间充质干细胞 (MSC) 的支架。通过细胞活力和增殖测定、成骨相关基因表达分析以及裸鼠皮下植入来评估复合生物墨水中间充质干细胞的存活和成骨能力。印刷过程对细胞活力影响不大。我们发现GO增强了细胞增殖，但对细胞活力没有显着影响。体外实验表明，GO 促进材料-细胞相互作用以及成骨相关基因的表达。体内实验表明，GO 缩短了材料的降解时间并增加了钙结节沉积。与纯GelMA相比，GO的添加创造了合适的微环境，促进加载的外源MSC在体外和体内的分化，为骨缺损的修复提供基础。