The pattern recognition receptor NOD2 mediates Staphylococcus aureus-induced IL-17C expression in keratinocytes

J Invest Dermatol. 2014 Feb;134(2):374-380. doi: 10.1038/jid.2013.313. Epub 2013 Jul 26.

Abstract

IL-17C is an important epithelial cell-derived cytokine activating innate immunity by the induction of antimicrobial peptides and cytokines. Here, we investigated the role of the cytosolic pattern recognition receptor nucleotide-binding oligomerization domain-containing protein 2 (NOD2) for the Staphylococcus aureus-mediated induction of IL-17C. Activation of NOD2 in HEK293 cells overexpressing NOD2 induced the IL-17C promoter, an activity that was significantly reduced in cells overexpressing the Crohn's disease-associated NOD2 mutation 3020insC (1007fs) or the Crohn's disease- and atopic dermatitis-associated NOD2-R702W variant. The first NF-κB-binding site in the IL-17C promoter was critical for NOD2-mediated IL-17C induction. Infection of human primary keratinocytes with S. aureus induced NOD2 and IL-17C gene expression. Overexpression of NOD2 in keratinocytes augmented S. aureus-mediated IL-17C gene expression as compared with NOD2-R702W overexpression. S. aureus-induced IL-17C expression was diminished in NOD2 small interfering RNA (siRNA)-treated keratinocytes. Moreover, significantly less S. aureus bacteria survived in keratinocytes overexpressing NOD2 but not in cells overexpressing the NOD2-R702W variant. Finally, S. aureus showed an increased survival in keratinocytes treated with NOD2 or IL-17C siRNA. In summary, our study provides evidence that S. aureus activates NOD2 in keratinocytes, resulting in an increased expression of IL-17C, a mechanism that may be dysregulated in atopic dermatitis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Dermatitis, Atopic / immunology
  • Dermatitis, Atopic / microbiology
  • Gene Expression / immunology
  • HEK293 Cells
  • Humans
  • Immunity, Innate / immunology
  • Interleukin-17 / genetics
  • Interleukin-17 / immunology*
  • Keratinocytes / cytology
  • Keratinocytes / immunology*
  • Keratinocytes / microbiology*
  • Nod2 Signaling Adaptor Protein / genetics
  • Nod2 Signaling Adaptor Protein / immunology*
  • Primary Cell Culture
  • Promoter Regions, Genetic / immunology
  • RNA, Small Interfering / genetics
  • Staphylococcal Infections / immunology*
  • Staphylococcus aureus / immunology*

Substances

  • IL17C protein, human
  • Interleukin-17
  • NOD2 protein, human
  • Nod2 Signaling Adaptor Protein
  • RNA, Small Interfering