The cytokine IFN gamma could protect cells from viral infections and belongs to the family of interferons. A lot of studies have shown that IFN gamma secreted by antigen triggered cell types, including T cells, naive CD4+ T cells, macrophages, dendritic cells, and B cells. IFN gamma plays an important role to trigger the macrophage act against a diverse group of microbial targets, and the pleiotropic molecule associated with antiproliferative, pro-apoptotic and antitumor mechanisms. Based on the effector cytokine considered as a major effector of immunity, it has been used in the treatment of several diseases.