Adhesion and Proliferation of Human Adipose-Derived Stem Cells on Titania Nanotube Surfaces

Abstract

When a biomaterial is implanted, the body reacts similar to an injury and stem cells are recruited to the implant site. Since, stem cells play an important role in tissue repair in the body, their interaction with biomaterials is critical for long-term success of medical devices. Surfaces with nanostructured features have been shown to alter cellular functionality in vitro and even improve fixation of the implant to the surrounding bone tissues in vivo. In this study, the effect of titania nanotube (NT) size and cell density on the adhesion and proliferation of human adipose-derived stem cells (ASCs) was evaluated. Although many studies have evaluated mesenchymal stem cells response on nanostructured surfaces, very few studies have explored the response of adipose-derived stem cells on titanium nanotube surfaces and none have explored the effect of cell density concurrent with nanotube size on ASC proliferation. Proliferation behavior of ASCs on NT surfaces and titanium control were investigated for a week using three different cell densities. The optimal cell density was 2500 cells/well and the smaller diameter NT exhibited higher ASC proliferation. This study confirms that NT surfaces promote ASC adhesion and proliferation. By more fully understanding the effect of nanostructure size on adhesion and proliferation of stem cells, implants could be specifically designed to achieve the optimal stem cell response from the tissue in which they are implanted. Additionally, the favorable response of ASC to these NT surfaces and determination of optimal cell density suggests a potential use in orthopedic tissue regeneration. When a biomaterial is implanted, the body reacts similar to an injury and stem cells are recruited to the implant site. Since, stem cells play an important role in tissue repair in the body, their interaction with biomaterials is critical for long-term success of medical devices. This study confirms that nanotube surfaces promote stem cell adhesion and proliferation.