CASP3 and acute respiratory distress syndrome: At 24 h post APAP-ALI, we show only 1.6% of neutrophils expressed active caspase 3 in Sema7a WT mice consistent with this finding, and this was significantly lower in Sema7a KO mice (0.7%, Fig. 10D-E, p = 0.0129), indicating less neutrophil apoptosis.