Thus, cell-to-cell interactions between inflammatory cells and TMJ SCs, mediated by TMJ SCs and soluble factors on the surface of inflammatory cells (such as MCP-1 or adhesion molecules such as ICAN-1 and LFA-1), may exacerbate the symptoms of synovitis or facilitate its transition to chronic inflammation in TMJ (Table 1) [94]. The gene discussed is CCL2; the disease is synovitis.