Immunoblot analysis revealed partially decreased caspase-3 and -7 cleavage in Ripk3−/−Casp8−/− BMDCs compared to WT or Ripk3−/− BMDCs following T4SS+Legionella infection (Fig. S1), indicating that caspase-8 is not the sole driver of DC apoptosis and that intrinsic apoptosis is also activated, as previously reported (69). This evidence concerns the gene CASP3 and legionellosis.