ACE2 and COVID-19: Evaluation of the expression of ACE2 and TMPRSS2 by RNA sequencing of the hearts in normal people and COVID-19 patients found that ACE2 was most highly expressed in pericytes and was also clearly expressed in other cells such as cardiomyocytes, indicating that the heart may be an important target for SARS-CoV-2 infection (45, 46).