Adhesion of Human Osteoblast-like Cells (Saos-2 cells) on Micro/nanopatterned Structures Sputter-Coated with Titanium

Abstract

Various designs are used for surface textures of implants to achieve bone osseointegration on the implant for clinical success. In this in vitro study, Ti sheets with groove and pillar shapes of 500 nm, 1 μm, and 2 μm were made by a nanoimprinting method. Osteoblast-like cells (Saos-2 cells) were seeded on the Ti sheets at a density of 5000 cells/cm² and cultured in DMEM containing 10% FBS. Cell viability was evaluated by calculating the number of cells that had proliferated and by observing vinculin formation to determine the presence of focal contacts 24 hours after seeding. On the groove and pillar structures, cells were growing at 1 hour and the number of cells at 24 hours was approximately twice that on smooth surfaces as a control. The number of cells on the 500-nm grooves and pillars was higher than that on the other patterns. After incubation for 24 hours, vinculin formation had extended to the ridges of the groove and pillar structures as an evidence of cell adhesion. The increase in vinculin was correlated with cell differentiation. The results indicate the importance of the biological effect of surface modification on Ti sheets and the potential use of surface modification to improve osseointegration.