To determine if the modulation of the actin cytoskeleton is similar during pathogenic and non-pathogenic bacterial infection, Casp-11−/− and Casp-1−/−Casp-11Tg macrophages were infected with E. coli. Vacuoles harboring these non-pathogenic bacteria fuse with the lysosome in the absence or presence of caspase-1 and caspase-11 (Fig. 1c,d). This evidence concerns the gene CASP1 and bacterial infectious disease.