Borrelia-induced cytokine production is mediated by spleen tyrosine kinase (Syk) but is Dectin-1 and Dectin-2 independent

Cytokine. 2015 Dec;76(2):465-472. doi: 10.1016/j.cyto.2015.08.005. Epub 2015 Aug 18.

Abstract

Although it is known that Borrelia species express sugar-like structures on their outer surface, not much is known about the role of these structures in immune recognition by host cells. Fungi, like Candida albicans, are mainly recognized by C-type lectin receptors, in specific Dectin-1 and Dectin-2. In this study we assessed the role of Dectin-1 and Dectin-2 in the recognition process of Borrelia spirochetes. Using specific inhibitors against these receptors on human cells did not influenced cytokine production. Individuals carrying a SNP leading to an early stop codon in the DECTIN-1 gene also did not lead to differential induction of Borrelia-dependent cytokines. After injection of live Borrelia into knee joints of Dectin-2 deficient mice a trend towards lower inflammation was observed. Inhibition of Syk in human cells resulted in lower cytokine production after Borrelia stimulation. In conclusion, Dectin-1 and Dectin-2 seem not to play a major role in Borrelia recognition or Borrelia-induced inflammation. However, Syk seems to be involved in Borrelia-induced cytokine production.

Keywords: Borrelia; Cytokines; Dectin-1; Dectin-2; Recognition; Syk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Borrelia burgdorferi / physiology*
  • Cytokines / biosynthesis*
  • Female
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Lectins, C-Type / genetics
  • Lectins, C-Type / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Protein-Tyrosine Kinases / metabolism*
  • Syk Kinase

Substances

  • Cytokines
  • Intracellular Signaling Peptides and Proteins
  • Lectins, C-Type
  • dectin 1
  • dectin-2, mouse
  • Protein-Tyrosine Kinases
  • SYK protein, human
  • Syk Kinase
  • Syk protein, mouse