Expression of SARS-CoV-2 entry receptors in the respiratory tract of healthy individuals, smokers and asthmatics

Respir Res. 2020 Sep 29;21(1):252. doi: 10.1186/s12931-020-01521-x.

Abstract

SARS-CoV-2 is causing a pandemic with currently > 29 million confirmed cases and > 900,000 deaths worldwide. The locations and mechanisms of virus entry into the human respiratory tract are incompletely characterized. We analyzed publicly available RNA microarray datasets for SARS-CoV-2 entry receptors and cofactors ACE2, TMPRSS2, BSG (CD147) and FURIN. We found that ACE2 and TMPRSS2 are upregulated in the airways of smokers. In asthmatics, ACE2 tended to be downregulated in nasal epithelium, and TMPRSS2 was upregulated in the bronchi. Furthermore, respiratory epithelia were negative for ACE-2 and TMPRSS2 protein expression while positive for BSG and furin, suggesting a possible alternative entry route for SARS-CoV-2.

Keywords: ACE-2; Asthma; Basigin; COVID-19; Coronavirus; Furin; Respiratory epithelium; SARS-CoV-2; Smoking; TMPRSS2.

Publication types

  • Comparative Study
  • Letter
  • Review

MeSH terms

  • Asthma / physiopathology
  • Asthma / virology*
  • COVID-19
  • Coronavirus Infections / genetics*
  • Databases, Factual
  • Gene Expression Regulation*
  • Humans
  • Pandemics
  • Pneumonia, Viral / genetics*
  • Receptors, Virus / genetics
  • Reference Values
  • Respiratory System / metabolism
  • Respiratory System / virology
  • Retrospective Studies
  • Serine Endopeptidases / genetics*
  • Severe Acute Respiratory Syndrome / metabolism
  • Severe Acute Respiratory Syndrome / virology*
  • Smoking / epidemiology*
  • Smoking / physiopathology
  • Virus Internalization

Substances

  • Receptors, Virus
  • Serine Endopeptidases
  • TMPRSS2 protein, human