Fig. 4.

ACE2 distribution and scores in respiratory tissues. a) ACE2 protein had progressively increased detection between donors in tissues from trachea (T), bronchi (B), bronchioles (Br), to alveoli (A), (P=0•0009, Cochran-Armitage test for trend). b) Single-cell RNA sequencing reanalyses of ACE2 mRNA transcript abundance in the alveoli shows variation between donors [26]. c-d) ACE2 protein scores from lung donors showed no differences based on sex or lower vs. upper ages (using median age as a cut-off) (A, P=0•7338 and B, P=0•7053, Mann-Whitney U test). e) ACE2 protein scores were elevated in young children (<10 yrs) compared to the remaining subjects (19-71 yrs) (P=0•0282 Mann-Whitney U test). f) Control and chronic disease groups did not have any significant differences in age (P=0•1362 Mann-Whitney U test). g) ACE2 protein scores for trachea, bronchi, bronchiole, and alveoli in control versus chronic disease groups (P= >0•9999, 0•6263, 0•0433, and 0•7359, respectively, Mann-Whitney U test). Each symbol represents one donor. CPM: counts per million. LOD: Limit of detection.