CASP1 and infection: We investigated whether infection with the P. aeruginosa strain, PAO1, induced expression of components of the NLRP3 inflammasome and found that a 6-h infection significantly increased expression of NLRP3, the adapter protein ASC, caspase-1, IL-1β, and IL-18 in BEAS-2B bronchial epithelial cells (Figure 1A,B).