Objective
Interleukin-12 is a pleiotropic cytokine that is produced by mononuclear phagocytes, dendritic cells and B cells, and it promotes the growth of activated T cells and NK cells. IL-12 selectively generates the development of naïve T cells into Th1 cells. IL-12 is effectively produced by macrophages upon stimulation with LPS, several bacteria and intracellular parasites. The goal of the present was to determine whether local overexpression of IL-12 converts an acute joint inflammation to a chronic destructive arthritis.