In addition, recent findings demonstrated that IL-6 presented both anti- and proinflammatory functions in “normal” and “stimulated” peripheral blood mononuclear cells, respectively, suggesting different roles of circulating IL-6 in different stages of disease.[45] Therefore, it is possible that serum IL-6 can act as both an inflammatory cytokine (high levels of which was observed in RA patients) and an antiinflammatory factor (genetically induced decrease of which could cause increased risk of RA in normal populations). The gene discussed is IL6; the disease is rheumatoid arthritis.