Mannan-binding lectin reduces CpG DNA-induced inflammatory cytokine production by human monocytes

Microbiol Immunol. 2015 Apr;59(4):231-7. doi: 10.1111/1348-0421.12245.

Abstract

Mannan-binding lectin (MBL) belongs to the collectin family and functions as an opsonin that can also initiate complement activation. Our previous study showed that MBL serves as a double-stranded RNA binding protein that attenuates polyriboinosinic-polyribocytidylic acid-induced TLR3 activation. Prompted by these findings, in the present study cross-talk between MBL and CpG-DNA-induced TLR9 activation was investigated. Here, it was found that MBL also interacts with the TLR9 agonist, CpG oligodeoxynucleotide (CpG-ODN), in a calcium-dependent manner. Purified MBL protein suppressed activation of nuclear factor-kappa B signaling and subsequent production of proinflammatory cytokines from human monocytes induced by CpG-ODN 2006. These observations indicate that MBL can down-regulate CpG DNA-induced TLR9 activation, emphasizing the importance of understanding the interaction of MBL with TLR agonist in host immune defense.

Keywords: CpG oligodeoxynucleotides; Toll like receptor 9; mannan binding lectin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cells, Cultured
  • Cytokines / immunology*
  • Humans
  • Inflammation / immunology*
  • Mannose-Binding Lectin / immunology*
  • Monocytes / immunology*
  • NF-kappa B / immunology
  • Oligodeoxyribonucleotides / immunology*
  • Toll-Like Receptor 9 / immunology

Substances

  • CPG-oligonucleotide
  • Cytokines
  • Mannose-Binding Lectin
  • NF-kappa B
  • Oligodeoxyribonucleotides
  • Toll-Like Receptor 9