ACE2 and acute respiratory distress syndrome: Imai et al.41 and our group42 revealed that ACE2 KO mice exhibit severe disease progression in comparison to WT mice following acid aspiration-mediated or sepsis and Pseudomonas aeruginosa infection-induced ALI/ARDS, as manifested by enhanced vascular permeability, increased lung edema, neutrophil accumulation, and worsened lung function.