ACE2 expression and localization are regulated by CFTR: implications beyond cystic fibrosis
As an inherited disorder characterized by severe pulmonary disease, cystic fibrosis (CF) could be considered a comorbidity for coronavirus disease 2019 (COVID-19)1. Instead, CF seems to constitute an advantage in COVID-19 infection2-5. To clarify whether host factors expressed by the CF epithelia may influence COVID-19 progression, we investigated the expression of SARS-CoV-2 receptor and coreceptors in primary airway epithelial cells. We found that angiotensin converting enzyme 2 (ACE2) expression and localization are regulated by cystic fibrosis transmembrane conductance regulator (CFTR) channels. Consistently, our results indicate that dysfunctional CFTR channels alter susceptibility to SARS-CoV-2 infection, resulting in reduced viral infection in CF cells. Depending on the pattern of ACE2 expression, the SARS-CoV-2 spike (S) protein induced high levels of Interleukin (IL)-6 in healthy donor-derived primary airway epithelial cells but a very weak response in primary CF cells. Collectively, these data support the hypothesis that CF condition is unfavorable for SARS-CoV-2 infection.