Interferon alpha and its contribution to autoimmunity

It is now well accepted that interferon (IFN) alpha plays a critical role in the pathogenesis and perpetuation of specific autoimmune diseases, including systemic lupus erythematosus (SLE), autoimmune thyroid disease and type 1 diabetes. IFN alpha-based treatments are widely used for the treatment of chronic viral infections, particularly chronic hepatitis C virus infection; however, several case reports have emerged describing autoimmune conditions that have developed during IFN alpha therapy. The data support the pathogenic potential of IFN alpha in autoimmunity, although it is clear that genetic and environmental factors are also key to the development of autoimmune conditions. Several points of interaction between IFN alpha and immune effector cells have been experimentally defined, the functional consequences of many of which remain poorly understood. This review describes the most recent data in support of an important role for IFN alpha in autoimmunity, particularly SLE, and the potential mechanisms by which IFN alpha contributes to immune dysfunction. Future approaches to IFN alpha modulation as a therapeutic strategy for use in the treatment of autoimmune diseases are also discussed.