基因激活钛表面促进体外成骨。
Gene-Activated Titanium Surfaces Promote In Vitro Osteogenesis.
出版信息
Int J Oral Maxillofac Implants. 2017 Mar/Apr;32(2):e83–e96. doi: 10.11607/jomi.5026. Epub 2016 Oct 5.
PURPOSE
Commercially pure titanium (CpTi) and its alloys possess favorable mechanical and biologic properties for use as implants in orthopedics and dentistry. However, failures in osseointegration still exist and are common in select individuals with risk factors such as smoking. Therefore, in this study, a proposal was made to enhance the potential for osseointegration of CpTi discs by coating their surfaces with nanoplexes comprising polyethylenimine (PEI) and plasmid DNA (pDNA) encoding bone morphogenetic protein-2 (pBMP-2).
MATERIALS AND METHODS
The nanoplexes were characterized for size and surface charge with a range of N/P ratios (the molar ratio of amine groups of PEI to phosphate groups in pDNA backbone). CpTi discs were surface characterized for morphology and composition before and after nanoplex coating using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRD). The cytotoxicity and transfection ability of CpTi discs coated with nanoplexes of varying N/P ratios in human bone marrow-derived mesenchymal stem cells (BMSCs) was measured via MTS assays and flow cytometry, respectively.
RESULTS
The CpTi discs coated with nanoplexes prepared at an N/P ratio of 10 (N/P-10) were considered optimal, resulting in 75% cell viability and 14% transfection efficiency. Enzyme-linked immunosorbent assay results demonstrated a significant enhancement in BMP-2 protein secretion by BMSCs 7 days posttreatment with PEI/pBMP-2 nanoplexes (N/P-10) compared to the controls, and real-time PCR data demonstrated that the BMSCs treated with PEI/pBMP-2 nanoplex-coated CpTi discs resulted in an enhancement of Runx-2, alkaline phosphatase, and osteocalcin gene expressions on day 7 posttreatment. In addition, these BMSCs demonstrated enhanced calcium deposition on day 30 posttreatment as determined by qualitative (alizarin red staining) and quantitative (atomic absorption spectroscopy) assays.
CONCLUSION
It can be concluded that PEI/pBMP-2 nanoplex (N/P-10)-coated CpTi discs have the potential to induce osteogenesis and enhance osseointegration.
目的
商用纯钛（CpTi）及其合金具有理想的机械和生物学性能，可用作骨科和牙科植入物。然而，在某些存在风险因素（如吸烟）的个体中，仍存在骨整合失败的情况，且较为常见。因此，在这项研究中，我们提出通过在 CpTi 圆盘表面涂覆包含聚乙烯亚胺（PEI）和编码骨形态发生蛋白-2（pBMP-2）的质粒 DNA（pDNA）的纳米复合物来增强 CpTi 圆盘的骨整合潜力。
材料和方法
使用一系列 N/P 比（PEI 的胺基团与 pDNA 主链中磷酸基团的摩尔比）对纳米复合物的粒径和表面电荷进行了表征。使用扫描电子显微镜（SEM）、原子力显微镜（AFM）、X 射线光电子能谱（XPS）和 X 射线粉末衍射（XRD）对涂覆纳米复合物前后的 CpTi 圆盘的形貌和组成进行了表面特征分析。通过 MTS 测定法和流式细胞术分别测量了涂覆不同 N/P 比纳米复合物的 CpTi 圆盘对人骨髓间充质干细胞（BMSCs）的细胞毒性和转染能力。
结果
当 N/P 比为 10（N/P-10）时，CpTi 圆盘涂覆的纳米复合物被认为是最佳的，其细胞活力为 75%，转染效率为 14%。酶联免疫吸附试验结果表明，与对照组相比，BMSCs 在经 PEI/pBMP-2 纳米复合物（N/P-10）处理 7 天后，BMP-2 蛋白的分泌显著增加，实时 PCR 数据表明，经 PEI/pBMP-2 纳米复合物涂覆的 CpTi 圆盘处理的 BMSCs 在处理后第 7 天，Runx-2、碱性磷酸酶和骨钙素基因表达增强。此外，通过定性（茜素红染色）和定量（原子吸收光谱法）检测，在处理后第 30 天，这些 BMSCs 显示出增强的钙沉积。
结论
可以得出结论，PEI/pBMP-2 纳米复合物（N/P-10）涂覆的 CpTi 圆盘具有诱导成骨和增强骨整合的潜力。
Zotero 插件