Abstract
People with cystic fibrosis should be considered at increased risk of developing severe symptoms of COVID-19. Strikingly, a broad array of evidence shows reduced spread of SARS-CoV-2 in these subjects, suggesting a potential role for CFTR in the regulation of SARS-CoV-2 infection/replication. Here, we analyzed SARS-CoV-2 replication in wild-type and CFTR-modified human bronchial epithelial cell lines and primary cells to investigate SARS-CoV-2 infection in people with cystic fibrosis. Both immortalized and primary human bronchial epithelial cells expressing wt or F508del-CFTR along with CRISPR/Cas9 CFTR-ablated clones were infected with SARS-CoV-2 and samples were harvested before and from 24 to 72 h post-infection. CFTR function was also inhibited in wt-CFTR cells with the CFTR-specific inhibitor IOWH-032 and partially restored in F508del-CFTR cells with a combination of CFTR modulators (VX-661+VX-445). Viral load was evaluated by real-time RT-PCR in both supernatant and cell extracts, and ACE-2 expression was analyzed by both western blotting and flow cytometry. SARS-CoV-2 replication was reduced in CFTR-modified bronchial cells compared with wild-type cell lines. No major difference in ACE-2 expression was detected before infection between wild-type and CFTR-modified cells, while a higher expression in wild-type compared to CFTR-modified cells was detectable at 72 h post-infection. Furthermore, inhibition of CFTR channel function elicited significant inhibition of viral replication in cells with wt-CFTR, and correction of CFTR function in F508del-CFTR cells increased the release of SARS-CoV-2 viral particles. Our study provides evidence that CFTR expression/function is involved in the regulation of SARS-CoV-2 replication, thus providing novel insights into the role of CFTR in SARS-CoV-2 infection and the development of therapeutic strategies for COVID-19.
Keywords: ACE-2; CFTR; CFTR inhibitor; SARS-CoV-2 virus; cystic fibrosis; human bronchial epithelial cells.
【저자키워드】 SARS-CoV-2 virus, ACE-2, cystic fibrosis, CFTR, CFTR inhibitor, human bronchial epithelial cells., 【초록키워드】 COVID-19, SARS-CoV-2, SARS-COV-2 infection, Infection, fibrosis, SARS-CoV-2 virus, flow cytometry, Replication, ACE-2, Spread, Viral, Viral load, cells, viral replication, Therapeutic strategies, epithelial cells, cystic fibrosis, real-time RT-PCR, inhibitor, expression, SARS-CoV-2 replication, therapeutic strategy, CFTR, Evidence, Combination, cell lines, epithelial cell, primary cells, primary cell, correction, Post-infection, Regulation, IOWH-032, increased risk, severe symptoms, wild-type, human bronchial epithelial cells, bronchial epithelial cells, primary human bronchial epithelial cells, clone, supernatant, SARS-CoV-2 viral particles, Cell, analyzed, were infected, involved, detectable, evaluated, inhibited, reduced, provide, subjects, restored, expressing, epithelial cell line, elicited, bronchial epithelial cell, was reduced, severe symptom, bronchial cell, immortalized, 【제목키워드】 SARS-CoV-2, Human, bronchial,