Wnt5a is a TLR2/4-ligand that induces tolerance in human myeloid cells

Commun Biol. 2019 May 9:2:176. doi: 10.1038/s42003-019-0432-4. eCollection 2019.

Abstract

Innate immune responses are rapid, dynamic and highly regulated to avoid overt reactions. This regulation is executed by innate immune tolerance mechanisms that remain obscure. Wnt5a is a signalling protein mainly involved in developmental processes and cancer. The effect of Wnt5a on inflammatory myeloid cells is controversial. Here, we combine primary cell cultures, in vitro binding studies, mass spectrometry and Drosophila protein modelling to show that Wnt5a is a direct ligand of toll-like receptor (TLR) 2 and 4. The binding promotes a MyD88-non-canonical nuclear factor of kappa B (NFκB) and AP-1 signalling cascade, with contradictory profiles in mouse (pro-inflammatory) and human (anti-inflammatory) myeloid immune cells. These data reveal that the true nature of Wnt5a in inflammatory cells, is to regulate TLR signals, and in human myeloid cells it acts as an endogenous, tolerance-associated molecular pattern (TAMP), inducing IL-10 and innate immune tolerance.

Keywords: Immune evasion; Monocytes and macrophages.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Cytokines / biosynthesis
  • Drosophila Proteins / chemistry
  • Drosophila Proteins / metabolism
  • Humans
  • Immune Tolerance
  • Immunity, Innate
  • Interleukin-10 / biosynthesis
  • Interleukin-10 / genetics
  • Intracellular Signaling Peptides and Proteins / chemistry
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Ligands
  • Mice
  • Models, Immunological
  • Models, Molecular
  • Myeloid Cells / immunology*
  • Myeloid Cells / metabolism
  • NF-kappa B / metabolism
  • Signal Transduction / immunology
  • Toll-Like Receptor 2 / immunology*
  • Toll-Like Receptor 2 / metabolism
  • Toll-Like Receptor 4 / immunology*
  • Toll-Like Receptor 4 / metabolism
  • Toll-Like Receptors / chemistry
  • Toll-Like Receptors / metabolism
  • Transcription, Genetic
  • Wnt-5a Protein / immunology*
  • Wnt-5a Protein / metabolism

Substances

  • Cytokines
  • Drosophila Proteins
  • IL10 protein, human
  • Intracellular Signaling Peptides and Proteins
  • Ligands
  • NF-kappa B
  • TLR2 protein, human
  • TLR4 protein, human
  • Tl protein, Drosophila
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • Toll-Like Receptors
  • WNT5A protein, human
  • Wnt-5a Protein
  • WntD protein, Drosophila
  • Interleukin-10