In the peripheral lung tissue of COPD patients (n = 12) and control smokers (n = 12) (Table 4), we measured semi-quantitatively the immune expression of RIG1, MDA5, LGP2, STING, DAI, FOXA3, IFNα, and IFNβ in bronchiolar epithelium, bronchiolar lamina propria, alveolar septa, and alveolar macrophages. Here, RIGI is linked to chronic obstructive pulmonary disease.