ACE2 and acute respiratory distress syndrome: Another possibility is that SARS-CoV-2 infection could reduce ACE2 expression due to attachment of the SARS-CoV-2 spike protein, resulting in induction of the ACE/angiotensin II (Ang-II)/angiotensin type I receptor (AT1R) axis, which is associated with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS).