MX1 and viral infectious disease: The antibody against melanoma differentiation-associated gene 5 (MDA5), which is a member of the RIG-I family of proteins, which detect cytoplasmic viral infection and are associated with innate immunity and type I IFN similar to MX1 [42], was found to be positive in serum from patients with clinically amyopathic dermatomyositis (CADM) and rapidly progressive interstitial lung disease (ILD) [43, 44].