Mechanisms of bone resorption: analysis of proinflammatory cytokines in peritoneal macrophages from titanium implant--an experimental design.

Cytokines, and interleukin-6 in particular, are inflammatory peptide mediators that are extensively studied as regulators of bone tissue homeostasis. They seem to be involved in osteoclast activation and bone resorption and probably play a role in osseointegrated implant rejection. In this study we investigate the ability of titanium implants to cause an imbalance in the homeostatic equilibrium of cytokines using the peritoneal cavity of DB-A2 mice as a model. The inflammatory response was evaluated as a messenger ribonucleic acid expression determined by the semiquantitative reverse transcriptase--polymerase chain reaction technique in peritoneal macrophages from titanium-implanted mice. Interleukin-6 release was detected by a specific quantitative enzyme-linked immunosorbent assay. Our results have shown that titanium implants do not significantly stimulate the proinflammatory cytokine system compared to the control group. The enzyme-linked immunosorbent assay test confirms, after a peak in secretion at day 1 compared with basal levels, a clear decrease in interleukin-6 at basal levels on following control at 6 and 9 days after implantation. The study of the interaction between implanted biomaterials and inflammatory mediators seems to be very promising. Perhaps a better understanding of the mechanisms of bone resorption could lead to finding a new clinical solution for patients with osseointegrated implant rejection.