P4 - In Vitro Study of the Biological Response of Mononuclear Cells in the Presence of Metallic Ions

Physiological repair following tissue damage or surgery is characterised by an initial inflammatory reaction, non-infectious, followed by a process of regeneration involving different cell elements that, through processes of differentiation and proliferation, work to restore the integrity of the tissue. The implantation of prosthetic joints, however, can give rise to a pathological skeletal tissue response that can result in aseptic mobilisation and implant failure. These complications are due to the chemical-physical interaction between the biomaterial and the host tissue. The implanted material may undergo processes of electrochemical degradation as a result of contact with bodily fluids and wear-related corrosion leading to the release of metallic ions. These can be eliminated through catabolic processes, accumulate in the area of release, or spread via the vascular system and accumulate in organs such as the liver, spleen and heart. The presence of small quantities of debris is compatible with tolerance of the implant, while high concentrations can set up a persistent inflammatory process and cause local or systemic toxicity reactions. The aim of this study was to evaluate the biological response of mononuclear cells from peripheral blood in the presence of metallic ions, evaluating both the presence, in the cytoplasm, of internalised metallic particles and the production of inflammatory cytokines.