The osteoimmunomodulatory effect of nanostructured TiF _x /TiO _x coating on osteogenesis induction

Abstract

Macrophages play a central role in the host response and the integration of implant materials. The nanostructured TiF x /TiO x coating (FOTi) on titanium surfaces has shown multiple properties, including antibacterial properties and bioactivity. However, little is known about the effects of these coatings on the regulation of macrophage activity and the subsequent immunomodulatory effects on osteogenesis. In this study, the behavior of macrophages on the FOTi samples was evaluated, and conditioned medium was collected and used to stimulate MC3T3-E1 cells in vitro. The results showed that the FOTi samples stimulated macrophage elongation and promoted the production of proinflammatory cytokines at 24 h, while induced macrophage polarization to the anti-inflammatory M2 phenotype at 72 h. Furthermore, the immune microenvironment generated by macrophage/ FOTi samples interactions effectively promoted the osteogenic differentiation of MC3T3-E1 cells, as evidenced by improved cell adhesion, enhanced alkaline phosphatase activity and extracellular matrix mineralization, and upregulated osteogenesis-related gene expression. In summary, the FOTi samples mediated macrophage phenotype behaviors and induced beneficial immunomodulatory effects on osteogenesis, which could be a potential strategy for the surface modification of bone biomaterials.

Implantable biomedical materials for treatment of bone infection

“…The titanium metal implant surface formed a nanostructure coating that stimulated macrophage elongation, promoted the production of proinflammatory cytokines, and induced macrophages to anti-inflammatory M2 phenotypes. This promote osteogenesis differentiation, such as cell adhesion, alkaline phosphatase activity, mineralization of the extracellular matrix, and raised the osteogenesis related gene expression ( Chen et al, 2021 ; Jiang et al, 2022 ). Zhao et al (2019) showed that the plasma electrolytic oxidation porous Mg-TiO 2 covered Ti surface not only promote osteoblast adhesion, proliferation, and differentiation, but also inhibited Staphylococcus engraftment and growth.…”