NLRP3 and infection: To test the hypothesis that inflammasome activation restricts Salmonella within human macrophages, we infected WT, NAIP-/-, and NLRC4-/- THP-1 macrophages with WT Stm in the presence or absence of the NLRP3 inhibitor MCC950 and determined the bacterial colony forming units (CFUs) at various timepoints post-infection to assay bacterial burdens.