Tumor necrosis factor-α/nuclear transcription factor-κB signaling in periprosthetic osteolysis

The role of tumor necrosis factor-α/nuclear transcription factor-κB signaling in the proinflammatory response to titanium particles in vitro and in vivo was examined. Using the mouse macrophage cell line J774, these cells were shown to produce an amount of tumor necrosis factor-α in response to titanium particles smaller than that produced by human peripheral blood monocytes. The production of tumor necrosis factor-α was preceded by a drop in cellular levels of inhibitory factor-κBα protein and translocation of p50/p65 nuclear transcription factor-κB to the nucleus 30 minutes after stimulation. Levels of tumor necrosis factor-α and inhibitory factor-κBα mRNA increased 30 minutes after stimulation.