CASP1 and bacterial infectious disease: In 1997, Thirumalai et al. discovered that Shigella dysenteriae could activate caspase-1 in human monocyte-derived macrophages and release mature IL-1β (Hilbi et al., 1997), and in 2001, two labs found that the macrophage death caused by bacterial infection was a mode of death that was different from apoptosis and defined it as caspase-1-dependent programmed necrosis (Boise and Collins, 2001; Cookson and Brennan, 2001).