Investigation of Type I Interferon Excess in Patients With Systemic Autoimmune Diseases and Genetic Type I Interferonopathies

Systemic autoimmune diseases associated with type I interferon (IFN-I) dysregulation, such as systemic lupus erythematosus, systemic sclerosis, myositis, and mixed or undifferentiated connective tissue diseases, and genetic type 1 interferonopathies are characterized by chronic and excession IFN-I signaling and production contributing to disease pathogenesis. Aberrant IFN-I production can be triggered through the activation of multiple signaling pathways, particularly those involving intracellular and extracellular RNA and DNA sensing receptors. We hypothesize that excessive IFN-I production results from an increased tonic activation state of nucleic acid sensors and/or an enhanced responsiveness of these sensors to endogenous nucleic acids, thereby sustaining pathological IFN-I signaling and chronic inflammation. The aim of this study is to characterize the type I interferon (IFN-I) response, defined by both the IFN-I gene signature and plasma IFN-α levels, following stimulation with a panel of ligands specific for DNA- and RNA-sensing pathways.