Behavior of Human Umbilical Vein Endothelial Cells on Titanium Surfaces Functionalized with VE-Cadherin Extracellular 1-4 Domains

Background: Angiogenesis is essential for the optimal functioning of orthopedic medical implants. Protein functionalization of implant surfaces can improve tissue integration through proper vascularization and prevent implant failure in patients lacking sufficient angiogenesis. Objective: The aim of this study was to evaluate the angiogenic activity of titanium surfaces functionalized with recombinant VE-cadherin extracelluar1-4 (VE-CADEC1-4) protein in human umbilical vein endothelial cells (HUVECs). Methods: After titanium discs were coated with recombinant VE-CADEC1-4 protein at appropriate concentrations, the behavior of HUVECs on the VE-CADEC1-4-functionalized titanium discs were evaluated by cell adhesion assay, proliferation assay, and real-time RT-PCR. Results: Recombinant VE-CADEC1-4–functionalized titanium surfaces improved the adhesion of HUVECs by 1.8-fold at the optimal concentration, and the proliferative activity was 1.3-fold higher than the control at 14 days. In addition, when angiogenesis markers were confirmed by real-time RT-PCR, PECAM-1 increased approximately 1.2-fold, TEK approximately 1.4-fold, KDR approximately 1.6-fold, and Tie-1 approximately 2.1-fold compared to the control. Conclusion: Recombinant VE-CADEC1-4–functionalized titanium surfaces improved cell adhesion, proliferation, and angiogenic differentiation of HUVECs, suggesting that the VE-CADEC1-4-functionalization of titanium surfaces can offer angiogenic surfaces with the potential to improve bone healing in orthopedic applications.