RIG-I-like receptors and autoimmune diseases

•RIG-I-like receptors (RLRs) play an essential role in triggering antiviral IFN responses by the recognition of viral RNAs.•Aberrant and sustained activation of RLRs can cause autoimmune diseases.•SNPs in IFIH1 have been reported in T1D, MS, psoriasis, selective IgA deficiency, dilated cardiomyopathy and SLE.•Mutations in IFIH1 have been reported in SLE, AGS and SMS patients.•MDA5 G821S mutant mice develop lupus-like nephritis.

Type I interferon (IFN) plays an essential role in antiviral innate immune responses and also in adaptive immune responses. Defects in the production of IFN markedly increase susceptibility to viral invasion and attenuate the acquired immunity. Recently an increased expression of type I IFN, also termed IFN signature, has been reported in patients with autoimmune diseases such as systemic lupus erythematosus (SLE) and Aicardi–Goutières syndrome (AGS). The evidence clearly shows that the initiation and termination of IFN production should be tightly controlled. RIG-I-like receptors (RLRs) are viral RNA sensors and are essential for type I IFN induction. We herein summarize recent reports on RLR mutations in patients and MDA5 mutant mice, and discuss possible mechanisms by which aberrant activation of RLRs can cause autoimmunity.