RT Journal Article SR Electronic T1 Nicotine upregulates ACE2 expression and increases competence for SARS-CoV-2 in human pneumocytes JF ERJ Open Research JO erjor FD European Respiratory Society SP 00713-2020 DO 10.1183/23120541.00713-2020 VO 7 IS 2 A1 Maggi, Fabrizio A1 Rosellini, Alfredo A1 Spezia, Pietro Giorgio A1 Focosi, Daniele A1 Macera, Lisa A1 Lai, Michele A1 Pistello, Mauro A1 de Iure, Antonio A1 Tomino, Carlo A1 Bonassi, Stefano A1 Russo, Patrizia YR 2021 UL http://openres.ersjournals.com/content/7/2/00713-2020.abstract AB The coronavirus disease 2019 (COVID-19) pandemic has a variable degree of severity according to underlying comorbidities and life-style. Several research groups have reported an association between cigarette smoking and increased severity of COVID-19. The exact mechanism of action is largely unclear.We exposed low angiotensin-converting enzyme 2 (ACE2)-expressing human pulmonary adenocarcinoma A549 epithelial cells to nicotine and assessed ACE2 expression at different times. We further used the nicotine-exposed cells in a virus neutralisation assay.Nicotine exposure induces rapid and long-lasting increases in gene and protein expression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor ACE2, which in turn translates into increased competence for SARS-CoV-2 replication and cytopathic effect.These findings show that nicotine worsens SARS-CoV-2 pulmonary infection and have implications for public health policies.Nicotine, the psychotropic substance of tobacco, in human lung adenocarcinoma A549 cells, induces increased gene and protein expression of the #SARSCoV2 receptor ACE2, which in turn translates into high SARS-CoV-2 replication and cytopathic effect https://bit.ly/36njkA9