The bottom cluster in Figure 4A are samples that show stronger innate immune response, including Calu3 cells infected with SARS-CoV-2, A549-ACE2 cells infected with SARS-CoV-2 at higher MOI (2), Vero E6 cells infected with SARS-CoV-2 and SARS, two BALF and two lung samples of COVID-19 patients. This evidence concerns the gene ACE2 and COVID-19.