SARS-CoV-2 employs angiotensin converting enzyme 2 (ACE2) as a receptor for internalization, and the binding affinity of the spike (S) protein of SARS-CoV-2 to ACE2 was found to be a major determinant of SARS-CoV-2 nasal epithelium cellular infection (Onabajo et al., 2020; Stanifer et al., 2020). Here, ACE2 is linked to infection.