a Box plot showing that the reduction of binding probability measured the S1-subunit-derivatized tip and a mixed culture of A549 and A549–ACE2 cells upon injection of the [22–57] ACE2-derived peptide. The square in the box indicates mean, the colored box indicates the 25th and 75th percentiles, and the whiskers indicate the highest and the lowest values of the results. b Overlay of eGFP and DIC images of a mixed culture of A549 and A549–ACE2–eGFP cells. FD-based AFM topography images (c, e) and the corresponding adhesion map (d, f) recorded in the specified area in (b) (scanned with a scan angle) before (c, d) and after (e, f) incubation of the tip with the [22–57] ACE2-derived peptide. The frequency of adhesion events is indicated. Data are representative of at least N = 4 cells from N = 2 independent experiments. P values were determined by two-sample t test in Origin. Source data are provided as a Source Data file.