Based on these preliminary results, we decided to investigate in vitro the effect of PD on (1) the release of inflammatory mediators and VEGF, (2) the release of CCL-23, a chemochine that acts through the CCR1 receptor and with properties similar to MIP-1γ, and finally (3) the migration induced by chemotactic stimuli and synovial fluids from patients with pyrophosphate crystal-induced arthritis. This evidence concerns the gene CCL23 and arthritic joint disease.