... fluid from RA patients contain increased concentrations of sev-eral chemokines, such as interleukin (IL)-8) ⁄ CXCL8,interferon-c (IFN-c)-inducible protein-10 ⁄ CXCL10,monokine induced by interferon-c ... anadditional 0–120 min. In addition, FLSs were incubated in the presence of recombinant human MCP-4 (100 ngÆmL)1)for 20 min with or without a specific inhibitor of MAPkinase kinase, PD98059 (Calbiochem, ... might haveroles not only in the proliferation of synovial cells butalso in the invasion of synovial cells, resulting in pan-nus formation and destruction of joints in RA. Takentogether with...