In PBMCs isolated from individuals vaccinated for COVID-19 (Fig. 6e), there was no change in the proportion of ACE2+ or ACE2me+ cells pre- and post-vaccination, but the expression intensity of ACE2me was significantly higher in PBMCs and CD14+ monocytes from vaccinated individuals (Fig. 6f, g and Supplementary Fig. 7f, g). This evidence concerns the gene ACE2 and COVID-19.