Expression of pro-IL-1β in THP1 parental, THP1 NLRP3-KO and THP1 Caspase-1-KO monocytes after E. coli LPS treatment, H. pylori infection and NLRP3 inflammasome activation with Nigericin were shown in Western blots in comparison with control GAPDH as loading reference (A). GAPDH, a known target for active caspase-1 [69] is also cleaved in THP1 parental cells but not in NLRP3-KO or caspase-1-KO cells after Nigericin treatment, which suggests pyroptotic death (A). NLRP3 inflammasome activation is evident with cleavage of pro-IL-1β and secretion of high amount of mature IL-1β from THP1 parental monocytes but not in NLRP3-KO or caspase-1-KO cells after Nigericin treatment, however, both knockout cells secreted basic background secretion after H. pylori infection, which again confirms the inflammasome or caspase-1-independent secretion of IL-1β by H. pylori (B). * p ≤ 0.05; ** p ≤ 0.01.