Differential expression of Angiotensin-Converting Enzyme 2 in Nasal Tissue of Patients with Chronic Rhinosinusitis with Nasal Polyps

The coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a pandemic and a global health emergency. The SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) is highly expressed in nasal epithelial cells and plays a major role in cellular entry leading to infection. High expression of ACE2 has been suggested to be a potential risk factor for virus infection and disease severity. However the profile of ACE2 gene expression in diseases of the upper airways remains poorly understood. We herein investigated ACE2 gene expression in the nasal tissues of a cohort of Swedish patients with chronic rhinosinusitis with nasal polyps (CRSwNPs) using RT-qPCR. ACE2 mRNA expression was significantly reduced in the nasal mucosa of CRSwNP patients compared to that of controls. Moreover, we observed a sex-dependant difference in nasal ACE2 expression, where significantly lower levels of the ACE2 transcript were detected in the nasal mucosa of only female CRSwNP patients. These findings indicate that CRSwNP patients with a decrease in ACE2 gene expression may thereby be less prone to be infected by SARS-CoV-2. These results enhance our understanding on the profile of ACE2 expression in the nasal mucosa of patients with upper airway diseases, and their susceptibility to infection with SARS-CoV-2.