The inflammasome proteins nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 1 (NLRP1), NLRP3, and nucleotide-binding oligomerization domain (NOD)-like receptor C4 (NLRC4) were associated with neutrophilic asthma and with sputum IL-1β protein levels, whereas eosinophilic asthma was associated with an IL-13-induced T<sub>H</sub>2 signature and IL-1 receptor-like 1 (IL1RL1) mRNA expression.
Caspase-8 was required for the production of IL-1 cytokines to promote Th2 immune response, which promotes the development of pulmonary eosinophilia and inflammation.