Macrophage proteome modulation induced by tribocorrosion of graphene oxide-hyaluronic acid-coated CoCr surfaces

Hip and knee implant components, such as femoral bearings, acetabulum liners, and stem taper junctions are subjected to mechanical stresses and undergo electrochemical processes that compromise their functionality. Cobalt-Chromium (CoCr) alloys are widely used as implants owing to their excellent mechanical properties, corrosion resistance, and biocompatibility. However, they are susceptible to simultaneous surface processes of wear and corrosion, known as tribocorrosion, which reduce their longevity and impact their performance. Our group has developed covalent multifunctional nanocoatings of graphene oxide (GO) and hyaluronic acid (HA) on CoCr surfaces providing chemical protection, reducing inflammatory response and enhancing wear-corrosion resistance. However, when the GO/HA nanocoating is disrupted by tribocorrosion, as takes place under in vivo conditions, macrophages, crucial cells for inflammation and healing, could exhibit a significantly different proteome. For this purpose, CoCr modified GO/HA surfaces were configured in a tribometer to simulate tribocorrosion of CoCrMo/CoCrMo joint implants, and the biological effects were studied in murine macrophages and analyzed via high-throughput proteomics. Simulated tribocorrosion testing revealed that metal degradation activates phagocytosis and increases endo-lysosomal membrane proteins, indicating enriched phagosomal compartment formation in macrophages. Additionally, macrophage exposure to worn CoCr-modified surfaces activates metal sensitization mechanisms and antigen presentation, leading to macrophage activation and polarization.