Notably, the elevated expression and production of caspase-4, IL-1β, and IL-18 were not observed in other asthma types, such as eosinophilic and paucigranulocytic asthma [33], which strongly suggests that the caspase-4 noncanonical inflammasome plays a pivotal role in neutrophilic asthma rather than in eosinophilic or paucigranulocytic asthma. Here, CASP4 is linked to asthma.