Single-cell analyses and host genetics highlight the role of innate immune cells in COVID-19 severity

Nat Genet. 2023 May;55(5):753-767. doi: 10.1038/s41588-023-01375-1. Epub 2023 Apr 24.

Abstract

Mechanisms underpinning the dysfunctional immune response in severe acute respiratory syndrome coronavirus 2 infection are elusive. We analyzed single-cell transcriptomes and T and B cell receptors (BCR) of >895,000 peripheral blood mononuclear cells from 73 coronavirus disease 2019 (COVID-19) patients and 75 healthy controls of Japanese ancestry with host genetic data. COVID-19 patients showed a low fraction of nonclassical monocytes (ncMono). We report downregulated cell transitions from classical monocytes to ncMono in COVID-19 with reduced CXCL10 expression in ncMono in severe disease. Cell-cell communication analysis inferred decreased cellular interactions involving ncMono in severe COVID-19. Clonal expansions of BCR were evident in the plasmablasts of patients. Putative disease genes identified by COVID-19 genome-wide association study showed cell type-specific expressions in monocytes and dendritic cells. A COVID-19-associated risk variant at the IFNAR2 locus (rs13050728) had context-specific and monocyte-specific expression quantitative trait loci effects. Our study highlights biological and host genetic involvement of innate immune cells in COVID-19 severity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19* / genetics
  • Genome-Wide Association Study
  • Humans
  • Immunity, Innate / genetics
  • Leukocytes, Mononuclear*
  • Single-Cell Analysis