Yang Jun, Qin Hanjun, Chai Yu, Zhang Ping, Chen Yirong, Yang Ke, Qin Min, Zhang Yifang, Xia Hong, Ren Ling, Yu Bin
Department of Orthopaedics, Nanfang Hospital, Southern Medical University; Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong, China.
Department of Orthopaedics, Guangzhou General Hospital of Guangzhou Military Command of PLA, Guangdong Key Lab of Orthopaedic Technology and Implant Materials, Key Laboratory of Trauma & Tissue Repair of Tropical Area of PLA, Guangzhou 510010, China.
J Orthop Translat. 2020 Dec 28;27:77-89. doi: 10.1016/j.jot.2020.10.004. eCollection 2021 Mar.
The antibacterial activity of copper (Cu)-alloy biomaterials has shown a great potential in clinical application. Here, we evaluated the osteogenesis and antibacterial effects of Ti6Al4V-6.5wt%Cu alloy in an in vivo model of infected bone defects and determine their responsible proteins and pathways using proteomics.
After bone defects were filled with Ti6Al4V and Ti6Al4V-6.5wt%Cu implants for 6 week, the tissue and bone samples around the implants were harvested for radiographic, micro-CT, histological, and bone-related gene expression analyses. An iTRAQ-based protein identification/quantification approach was used to analyze the osteogenic and antibacterial effects of Ti6Al4V-6.5wt%Cu alloy.
Imaging and histological results showed Ti6Al4V alloy induced a stronger inflammatory response than Ti6Al4V-6.5wt%Cu alloy; imaging results and osteogenic protein levels showed Ti6Al4V-6.5wt%Cu alloy exerted a stronger osteogenic effect. In vitro experiment, we found the Ti6Al4V-6.5wt%Cu had significant antibacterial effects and inhibited the activity of Staphylococcus aureus in the early stage. In addition, the bacterial biofilm formed in Ti6Al4V-6.5wt%Cu group was significantly lower than that in Ti6Al4V group. Proteomic screening of 4279 proteins resulted in 35 differentially expressed proteins for further examination which were mainly associated with the cellular process, metabolic process, stimulus response, and cellular component organization. In further exploration of the mechanism of osteogenic mineralization of Ti6Al4V-6.5wt%Cu alloy, we found out SDC4 and AGRN were the top two target proteins associated with osteogenic differentiation and bone mineralization.
Ti6Al4V-6.5wt%Cu alloy shows a great potential as a bone implant material due to its positive effects against bacterial infection and on bone formation.
At present, titanium alloys and other non-antibacterial metal materials are used in orthopedic internal fixation operations. Our study demonstrates that Ti6Al4V-6.5wt%Cu alloy has good antibacterial and osteogenic effects in vivo and in vitro. This means that Ti6Al4V-6.5wt%Cu alloy may become a new kind of antimicrobial metallic material as internal fixation material to continuously exert its antimicrobial effects and reduce the infection rate after clinical internal fixation.
铜（Cu）合金生物材料的抗菌活性在临床应用中显示出巨大潜力。在此，我们在感染性骨缺损的体内模型中评估了Ti6Al4V - 6.5wt%Cu合金的成骨作用和抗菌效果，并使用蛋白质组学确定其相关蛋白和途径。
将Ti6Al4V和Ti6Al4V - 6.5wt%Cu植入物植入骨缺损处6周后，采集植入物周围的组织和骨样本进行影像学、显微CT、组织学和骨相关基因表达分析。采用基于iTRAQ的蛋白质鉴定/定量方法分析Ti6Al4V - 6.5wt%Cu合金的成骨和抗菌效果。
影像学和组织学结果显示，Ti6Al4V合金比Ti6Al4V - 6.5wt%Cu合金诱导更强的炎症反应；影像学结果和成骨蛋白水平显示，Ti6Al4V - 6.5wt%Cu合金具有更强的成骨作用。体外实验发现，Ti6Al4V - 6.5wt%Cu具有显著的抗菌效果，并在早期抑制金黄色葡萄球菌的活性。此外，Ti6Al4V - 6.5wt%Cu组形成的细菌生物膜明显低于Ti6Al4V组。对4279种蛋白质进行蛋白质组学筛选，得到35种差异表达蛋白质以供进一步研究，这些蛋白质主要与细胞过程、代谢过程、刺激反应和细胞成分组织有关。在进一步探索Ti6Al4V - 6.5wt%Cu合金成骨矿化的机制时，我们发现SDC4和AGRN是与成骨分化和骨矿化相关的前两个靶蛋白。
Ti6Al4V - 6.5wt%Cu合金因其对细菌感染和骨形成的积极作用，作为骨植入材料具有巨大潜力。
目前，骨科内固定手术中使用钛合金等非抗菌金属材料。我们的研究表明，Ti6Al4V - 6.5wt%Cu合金在体内外均具有良好的抗菌和成骨效果。这意味着Ti6Al4V - 6.5wt%Cu合金可能成为一种新型抗菌金属材料作为内固定材料，在临床内固定后持续发挥抗菌作用，降低感染率。
