ACE-2 Expression in the Small Airway Epithelia of Smokers and COPD Patients: Implications for COVID-19

Janice M Leung; Chen Xi Yang; Anthony Tam; Tawimas Shaipanich; Tillie L Hackett; Gurpreet K Singhera; Delbert R Dorscheid; Don D Sin

We also determined protein expression of ACE-2 in resected lung tissue specimens. These samples were obtained from 10 current smokers with COPD (mean±SD, FEV1/FVC 61±7%), 9 non-smoker controls (FEV1/FVC 85±2%), and 8 healthy current smokers (FEV1/FVC 78±6%). Human lung tissue samples were obtained with informed consent from patients undergoing thoracic surgery as part of the James Hogg Lung Registry (UBC/PHC REB Protocol H00-50110). Formalin-fixed paraffin-embedded human lung tissues were stained with antibody against ACE-2 (Ab15348; Abcam) using the Bond Polymer Refine Red Detection kit on the Leica Bond Autostainer as previously described [15] . Airway epithelial-specific ACE-2 protein intensity was quantified using the Aperio imaging system with normalization to the length of the basement membrane (Leica Biosystem; Concord, Ontario).