Mesenchymal Stem Cells Differentiation on Hierarchically Micro/Nano-Structured Titanium Substrates

Surface topography of a biomaterial plays an essential role in the regulation of cell adhesion, proliferation, and differentiation. To investigate the influence of hierarchically micro/nano-structured substrates on the differentiation of mesenchymal stem cells (MSCs), a series of micro-, nano-, and micro/nano-structured titanium substrates were fabricated via dual acid etching and/or anodic oxidation. The morphologies of titanium substrates were characterized by field emission scanning electron microscopy (FE-SEM) and contact angle measurement, respectively. The differentiation of MSCs adhered to different substrates was investigated in vitro. Compared to native titanium, micro/nano-structured titanium substrates improved the alkaline phosphatase (ALP) production and mineralization of MSCs. More importantly, micro/nano-structured titanium substrates demonstrated great potential to induce the differentiation of MSCs, which was revealed by the expressions of osteocalcin (OCN) and osteopontin (OPN). The study provides a potential alternative to generate hierarchically micro/nano-structured titanium-based implant for enhanced osseointegration.