TABLE 1

Expression of genes/proteins related to severe acute respiratory syndrome-coronavirus-2 infection in controls# and COPD patients

First author [ref.]Key findingsSample typePatient groups
ACE2FurinTMPRSS2
Cai [40]No differenceBronchial epitheliumCurrent smoker versus never-smoker
COPD versus ex-smoker
Leung [28]Not quantifiedNot quantifiedBronchial epitheliumCurrent smoker versus never-smoker
COPD versus controls
Negative correlation with FEV1 %
Smith [41]Not quantifiedNo differenceWhole lung tissueCurrent smoker versus never-smoker
COPD versus current smoker
Brake [27]Not quantifiedNot quantifiedBronchial epitheliumCOPD versus controls
Zhang [29]No differenceBronchial epitheliumCurrent smoker versus never-smoker
Radzikowska [42]Not quantifiedNot quantifiedBronchial biopsyCurrent smoker versus never-smoker
Higham [43]No differenceNo differenceBronchial epitheliumNegative correlation with FEV1 %
Overweight COPD versus not overweight COPD

↑: increase in cell number; FEV1: forced expiratory volume in 1 s. #: controls were a mixture of never-, ex- and current smokers; : data not presented in manuscript.