School of Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
Macromol Biosci. 2022 Jun;22(6):e2200071. doi: 10.1002/mabi.202200071. Epub 2022 Apr 11.
The surface of metal implants serves as a powerful signaling cue for cells. Its properties play an essential role in stabilizing the bone-implant interface and facilitating the early osseointegration by encouraging bone deposition on the surface. However, effective strategies to deliver cells to the metal surfaces are yet to be explored. Here, a bioprinting process, called reactive jet impingement (ReJI), is used to deposit high concentrations (4 × 10 cells mL ) of mesenchymal stromal cells (MSCs) within hydrogel matrices directly onto the titanium alloy surfaces that vary in surface roughness and morphology. In this proof-of-concept study, cell-hydrogel-metal systems are fabricated with the aim of enhancing bioactivity through delivering MSCs in hydrogels at the bone-implant interface. These results show that the high cell concentrations encourage quick cell-biomaterial interactions at the hydrogel-metal surface interface, and cell morphology is influenced by the surface type. Cells migrate from the hydrogels and deposit mineralized matrix rich in calcium and phosphorus on the titanium alloy surfaces. The authors demonstrate that ReJI bioprinting is a promising tool to deliver cells in a 3D environment before implantation that can be used when developing a new generation of medical devices for bone tissue engineering.
金属植入物的表面是细胞的一个强大信号提示。其特性在稳定骨-植入物界面和促进早期骨整合方面起着至关重要的作用，方法是鼓励在表面进行骨沉积。然而，将细胞递送到金属表面的有效策略仍有待探索。在这里，使用一种称为射流冲击反应（ReJI）的生物打印工艺，将高浓度（4×10^6 个细胞 mL^-1）的间充质基质细胞（MSCs）直接沉积在钛合金表面的水凝胶基质中，这些钛合金表面的表面粗糙度和形态有所不同。在这项概念验证研究中，制造了细胞-水凝胶-金属系统，旨在通过在骨-植入界面的水凝胶中递送至 MSC 来提高生物活性。这些结果表明，高细胞浓度可促进水凝胶-金属表面界面处的快速细胞-生物材料相互作用，并且细胞形态受表面类型的影响。细胞从水凝胶中迁移，并在钛合金表面沉积富含钙和磷的矿化基质。作者证明，ReJI 生物打印是一种在植入前在 3D 环境中递细胞的有前途的工具，可用于开发新一代用于骨组织工程的医疗设备。
