The role of interleukin-15 in the spectrum of inflammatory diseases

IL-15 exerts its pathogenetic activity by the induction of a deregulated activation of innate and adaptive arms of the immune system, at the crossroad of autoimmune and autoinflammatory disorders. During RA, IL-15 mediates the production from T cells and macrophages of TNF, which may induce further production of IL-15 by synoviocytes via a vicious pathogenic loop. During Still's disease, together with IFN-I, IL-15 promotes the expansion of NK cells and of CD38+HLA-DR+ T cells, which are highly activated in disease life-threatening evolution. Thus, novel IL-15-targeted therapeutic strategies could be explored to improve the management of systemic inflammatory diseases.