Porous titanium scaffolds with modified surface: in vitro cell biology assessment

Interaction of host cells with a biomaterial surface is important for biocompatibility and thus is essential for biomedical applications. Therefore investigations are undertaken to scrutinize for an appropriate surface coating with physical and chemical properties minimizing undesirable activation of immunological response. For this the current study was aimed at examining the effects of different surface modifications of titanium by its coating with ceramic materials - hydroxyapatite, bioglass and CaO-SiO2on osteoblast morphology and secretory activity. Titanium is known for its excellent mechanical properties but its surface has low bioactivity. We report that CaO-SiO2coating decreased a number of attached osteoblasts and altered their morphology. Moreover, the ceramic coatings temporarily upregulated release of pro-inflammatory cytokines IL-6 (all of them) and TNF-α (CaO-SiO2). However, overall the levels of the cytokines were low. In contrast, levels of neutrophil-attracting chemokine IL-8 were the highest. IL-8 was produced mostly by cells incubated with hydroxyapatite titanium coating in contrary to those incubated with either bioglass or CaO-SiO2titanium modifications. In conclusion, the titanium coated with ceramics such as hydroxyapatite or bioglass had the best effect on cell adhesion; however, hydroxyapatite might potentially stimulate destructive neutrophils while CaO-SiO2-coating has a negative effect on cell adhesion.