ACE2 and acute respiratory distress syndrome: With the increased studies and researches on COVID-19, it is clear that SARS-CoV-2, an enveloped, positive-sense single-stranded RNA virus [1], is the pathogen causing this global pandemic; it invades the host cells through angiotensin-converting enzyme 2 (ACE2) receptor [2, 3] and results in respiratory failure and a lethal state of acute respiratory distress syndrome (ARDS) by diffuse alveolar damage, pulmonary capillary congestion, and cytokine storm [4, 5].