Angiotensin-converting enzyme 2 (ACE-2) is the main cell entry receptor for severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2), thus playing a critical role in causing Coronavirus disease 2019 (COVID-19). The role of smoking habit in the susceptibility to infection is still controversial. In this study we correlated lung ACE-2 gene expression with several clinical/pathological data to explore susceptibility to infection. This is a retrospective observational study on 29 consecutive COVID-19 autopsies. SARS-CoV-2 genome and ACE-2 mRNA expression were evaluated by real-time polymerase chain reaction in lung tissue samples and correlated with several data with focus on smoking habit. Smoking was less frequent in high than low ACE-2 expressors ( p = 0.014). A Bayesian regression also including age, gender, hypertension, and virus quantity confirmed that smoking was the most probable risk factor associated with low ACE-2 expression in the model. A direct relation was found between viral quantity and ACE-2 expression ( p = 0.028). Finally, high ACE-2 expressors more frequently showed a prevalent pattern of vascular injury than low expressors ( p = 0.049). In conclusion, ACE-2 levels were decreased in the lung tissue of smokers with severe COVID-19 pneumonia. These results point out complex biological interactions between SARS-CoV-2 and ACE-2 particularly concerning the aspect of smoking habit and need larger prospective case series and translational studies.
【저자키워드】 COVID-19, SARS-CoV-2, smoking, Angiotensin converting enzyme receptor, 【초록키워드】 coronavirus disease, Coronavirus disease 2019, Severe COVID-19 pneumonia, COVID-19 pneumonia, Gene Expression, Bayesian, susceptibility, Infection, lung, Gender, smoking, risk factor, virus, hypertension, observational study, ACE-2, Severe acute respiratory syndrome, polymerase chain reaction, Viral, SARS-CoV-2 genome, real-time polymerase chain reaction, age, respiratory, expression, Critical, severe acute respiratory syndrome-coronavirus-2, Smokers, Angiotensin-converting enzyme, retrospective, angiotensin, Autopsies, focus, Chain Reaction, susceptibility to infection, smoker, Vascular injury, acute respiratory syndrome, enzyme, complex, lung tissue, aspect, lung tissue samples, mRNA expression, prevalent, polymerase chain, cell entry receptor, evaluated, case sery, less, correlated, concerning, translational, biological interaction, expressor, lung tissue sample, 【제목키워드】 Lower, with COVID-19,