IL1B and infection: Prior studies have demonstrated that infections with EPEC, EHEC and Citrobacter rodentium could elicit inflammasomes in macrophages and epithelial cells [17,19], but our study is the first to show that A/E pathogens could actively suppress IL-1β production and that a T3SS-dependent effector, NleA, is used to inhibit host inflammasome formation in macrophage-like cells.