In conditions without ENC, we observed infected cells similar to the above-mentioned experiments: 2.31 ± 0.34% and 2.74 ± 0.43% in cells + SARS-CoV-2 pv, cells + (ACE2 + SARS-CoV-2 pv), respectively; however, the condition of cells + (IgG + SARS-CoV-2 pv) did have lower infection: 1.55 ± 0.26% infected cells, (p = 0.009, n = 11, Fig. 7). Here, ACE2 is linked to infection.