IL-6 during viral-induced chronic autoimmune myocarditis

Interleukin (IL)-6 is a pleiotropic cytokine that plays a key role in a wide variety of diseases. Based on a number of adjuvant-induced experimental models, IL-6 is critical to the development of autoimmune diseases including experimental autoimmune encephalomyelitis, adjuvant-induced arthritis, and experimental autoimmune myocarditis. However, whether it plays a pathogenic role in viral-induced autoimmune myocarditis has been less well defined. While experimental models of myocarditis have clearly linked IL-6 to the generation of pathogenic autoreactive T cells, IL-6 has exhibited a protective role in autoimmune disease development in viral-induced disease models. As pathogen infection has been linked to the majority of myocarditis patients, treatments aimed at decreasing IL-6 levels in the hopes of limiting the autoimmune response run the risk of increasing disease severity.