CD169/SIGLEC1 is expressed on circulating monocytes in COVID-19 and expression levels are associated with disease severity

Infection. 2021 Aug;49(4):757-762. doi: 10.1007/s15010-021-01606-9. Epub 2021 Apr 6.


Coronavirus disease 2019 (COVID-19) is caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Type I interferons are important in the defense of viral infections. Recently, neutralizing IgG auto-antibodies against type I interferons were found in patients with severe COVID-19 infection. Here, we analyzed expression of CD169/SIGLEC1, a well described downstream molecule in interferon signaling, and found increased monocytic CD169/SIGLEC1 expression levels in patients with mild, acute COVID-19, compared to patients with severe disease. We recommend further clinical studies to evaluate the value of CD169/SIGLEC1 expression in patients with COVID-19 with or without auto-antibodies against type I interferons.

Keywords: CD169; COVID-19; SARS-CoV-2; SIGLEC1; Type I interferons.

Publication types

  • Observational Study

MeSH terms

  • Aged
  • COVID-19 / immunology*
  • Female
  • Hospitalization
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Monocytes / immunology*
  • Retrospective Studies
  • SARS-CoV-2 / physiology*
  • Severity of Illness Index
  • Sialic Acid Binding Ig-like Lectin 1 / biosynthesis
  • Sialic Acid Binding Ig-like Lectin 1 / blood*
  • Up-Regulation


  • Sialic Acid Binding Ig-like Lectin 1