Insights into adhesion and osteogenesis of bone marrow stromal cells promoted by surface nanopatterns

The surface property of biomaterials has a profound influence on the adhesion and biofunction of mesenchymal stem cells, which is vital for successful implantation and regeneration. Nanotopological surface is capable of mimicking bone's extracellular matrix (ECM) to regulate cell behavior, the understanding of which however remains elusive. In this study, we decoupled the effect of nanotopological cues from two perspectives: nanostructure and specific surface area. Bone marrow-derived mesenchymal stem cells (BMSCs) displayed stable and organized F-actin fibers, forming intricate myosin networks on the poly (ε-caprolactone) (PCL) substrate decorated with a well-defined nanopattern that was formed by the PCL lamellae. The cell spreading and myosin activation were limited when the specific surface area of the nanopattern was reduced. These findings illustrate that the specific surface area of the nanopatterned surface is a dominant regulator for cell mechanosensing. Our results highlight the potential of optimizing biomaterial interfaces to enhance cell adhesion and functionality for bone regeneration.