In addition, during infection with Yp-YopJCO92 orYp-YopJC172A, higher amounts of IL-1β were secreted fromIkkβΔ BMDMs as compared toIkkβF/F macrophages (Figure 4B), consistent with the idea that theNF-κB pathway negatively regulates processing and secretion of IL-1β viacontrol of caspase-1 activation [7]. This evidence concerns the gene IL1B and infection.