Helmers SB, et al. - In symptomatic and asymptomatic muscle tissues of patients with polymyositis (PM) and dermatomyositis (DM), researchers gauged the expression of IL-18 and the impact of conventional immunosuppressive treatment on such expression. Among symptomatic, asymptomatic and healthy muscles, they noted no difference in the number of IL-18 positive capillaries. In biopsies from patients receiving and improving with immunosuppressive treatment, total IL-18 expression was lower, especially the number of IL-18 positive inflammatory cells, but not the number of IL-18 positive capillaries. The number of IL-18 positive capillaries was consistent with the significantly decreased expression of CD68⁺ macrophages. In muscle tissue, IL-18 is highly expressed in the context of inflammatory myopathies and a novel therapeutic target in future could be provided by it based on its plausible effector functions.