Furthermore, inflammatory activities of IL-18, together with the induction of Th1 cytokine IFN-γ and the activation of Th cells, natural killer cells (NK), and cytotoxic T lymphocytes-inflammatory chemokines, may even enhance the Th1-mediated inflammatory process, the activation of NK and T cells, and the migration of macrophages for initiating and perpetuating the Th1 immune response in SLE. This evidence concerns the gene IFNG and systemic lupus erythematosus.