CASP1 and infection: Furthermore, cell death and caspase-1 cleavage were comparable between WT and Mefv–/–, Zbp1–/– or Mefv–/–Zbp1–/– BMDMs treated with the synthetic AIM2 inflammasome ligand poly(dA:dT) (Extended Data Fig. 4f–h), suggesting that infection is a unique trigger causing Pyrin and ZBP1 to cooperate to facilitate AIM2-mediated caspase-1 activation, cytokine release and cell death.