IL18 and chronic obstructive pulmonary disease: As well-increased gene expression of NLRP3, IL-1β, and IL-18 has been found in PBMCs from COPD patients compared to smokers (92), while no differences of NLRP3, IL-1β, and IL-18 in bronchial epithelial were observed in severe stable COPD patients compared to current smokers (93), see also Table 3.