MatureIL-1β was absent in supernatants isolated fromcasp-1-/- BMDMs infected withYp-YopJKIM (Figure S5 in Text S1), indicating that the processing andrelease of IL-1β during infection of wild-type macrophages withYp-YopJKIM occurred in a caspase-1-dependent manner. Here, CASP1 is linked to infection.