Proteomics of regenerated tissue in response to a titanium implant with a bioactive surface in a rat tibial defect model

Background: Due to their excellent mechanical and biocompatibility properties, titanium-based implants are successfully used as biomedical devices. However, when new bone formation fails for different reasons, impaired fracture healing will become a clinical problem and will affect the patient's quality of life. This study proposes to design a new bioactive surface of titanium implants with a synergetic PEG biopolymer-based composition for gradual delivery of growth factors (FGF2, VEGF, and BMP4) during bone healing. Methods: The optimal architecture of non-cytotoxic polymeric coatings deposited by dip coating under controlled parameters was assessed both in cultured cells and on rat in vivo animal model (100% viability). Results: Notably, the titanium adsorbed polymer matrix induced an improved healing process when compared with the individual action of each biomolecules. High-performance mass spectrometry analysis demonstrated that recovery after a traumatic event is governed by specific differentially regulated proteins, acting in a coordinated response to the external stimulus. Predicted protein interactions shown by STRING analysis were well organized in hub-based networks related with response to chemical, wound healing and response to stress pathways. Conclusions: The described functional polymer coatings of the titanium implants demonstrated the significant improvement of bone healing process after injury.