The interaction of COVID-19 with ACE2 downregulates ACE2 expression, which results in a corresponding increase in inflammatory angiotensin II (1–8) via unopposed ACE, and a decrease in anti-inflammatory angiotensin (1–7) due to downregulated ACE2 (Figure 1B) (Silhol et al., 2020). Here, ACE2 is linked to COVID-19.