Department of Orthopedic, Spinal Pain Research Institute, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200072, P. R. China.
Institute of Translational Medicine, Shanghai University, Shanghai 200444, P. R. China.
ACS Appl Mater Interfaces. 2022 Aug 17;14(32):36315-36330. doi: 10.1021/acsami.2c05794. Epub 2022 Aug 4.
The formation and metabolic balance of bone tissue is a controllable process of biomineralization, which is regulated by various cells, biomolecules, and ions. Enzyme molecules play an important role in this process, and alkaline phosphatase (ALP) is one of the most critical factors. In this study, inspired by the process of bone biomineralization, a biomimetic strategy is achieved for the preparation of mineralized ALP nanoparticles (MALPNs), by taking advantages of the unique reaction between ALP and calcium ions in Dulbecco's modified Eagle's medium. Benefiting from the mild biomineralization reaction, the MALPN system highly maintains the activity of ALP. Furthermore, the in vitro studies show that the MALPN system significantly enhances the proliferation of bone marrow mesenchymal stem cells and upregulates their osteogenic differentiation. When evaluated as synthetic graft materials for bone regeneration, the MALPN-incorporated gelatin methacryloyl graft shows excellent mechanical properties, a sustained release profile of ALP, and high biocompatibility and efficacy in guiding bone regeneration and vascularization for critical-sized rat calvarial defect. Moreover, we also demonstrate that the biomimetic mineralization strategy can be adopted for other proteins such as acid phosphatase, bovine serum albumin, fibrinogen, and gelatin, suggesting its universality for constructing mineralized protein-/enzyme-based bioactive materials for the application of tissue regeneration.
骨组织的形成和代谢平衡是一个可控制的生物矿化过程，由各种细胞、生物分子和离子调节。酶分子在这个过程中起着重要的作用，其中碱性磷酸酶（ALP）是最关键的因素之一。在这项研究中，受骨生物矿化过程的启发，我们采用了一种仿生策略来制备矿化 ALP 纳米颗粒（MALPNs），利用 ALP 和钙在 Dulbecco 改良 Eagle 培养基中的独特反应。得益于温和的生物矿化反应，MALPN 系统高度保持了 ALP 的活性。此外，体外研究表明，MALPN 系统显著促进了骨髓间充质干细胞的增殖，并上调了其成骨分化。当作为骨再生的合成移植物材料进行评估时，MALPN 掺入的明胶甲基丙烯酰基接枝显示出优异的机械性能、ALP 的持续释放特性以及高度的生物相容性和功效，可促进骨再生和血管化，用于治疗大鼠颅骨临界大小缺损。此外，我们还证明了这种仿生矿化策略可以应用于其他蛋白质，如酸性磷酸酶、牛血清白蛋白、纤维蛋白原和明胶，这表明它在构建基于矿化蛋白质/酶的生物活性材料以应用于组织再生方面具有普遍性。
