Borrelia burgdorferi Induces TLR2-Mediated Migration of Activated Dendritic Cells in an Ex Vivo Human Skin Model

PLoS One. 2016 Oct 3;11(10):e0164040. doi: 10.1371/journal.pone.0164040. eCollection 2016.

Abstract

Borrelia burgdorferi is transmitted into the skin of the host where it encounters and interacts with two dendritic cell (DC) subsets; Langerhans cells (LCs) and dermal DCs (DDCs). These cells recognize pathogens via pattern recognition receptors, mature and migrate out of the skin into draining lymph nodes, where they orchestrate adaptive immune responses. In order to investigate the response of skin DCs during the early immunopathogenesis of Lyme borreliosis, we injected B. burgdorferi intradermally into full-thickness human skin and studied the migration of DCs out of the skin, the activation profile and phenotype of migrated cells. We found a significant increase in the migration of LCs and DDCs in response to B. burgdorferi. Notably, migration was prevented by blocking TLR2. DCs migrated from skin inoculated with higher numbers of spirochetes expressed significantly higher levels of CD83 and produced pro-inflammatory cytokines. No difference was observed in the expression of HLA-DR, CD86, CD38, or CCR7. To conclude, we have established an ex vivo human skin model to study DC-B. burgdorferi interactions. Using this model, we have demonstrated that B. burgdorferi-induced DC migration is mediated by TLR2. Our findings underscore the utility of this model as a valuable tool to study immunity to spirochetal infections.

MeSH terms

  • Biomarkers
  • Borrelia burgdorferi / physiology*
  • Cell Movement / immunology*
  • Cell Survival
  • Cytokines / metabolism
  • Dendritic Cells / immunology*
  • Dendritic Cells / metabolism*
  • Humans
  • Lyme Disease / immunology
  • Lyme Disease / metabolism
  • Lyme Disease / microbiology
  • Skin / immunology
  • Skin / metabolism
  • Skin / microbiology
  • Toll-Like Receptor 2 / metabolism*

Substances

  • Biomarkers
  • Cytokines
  • Toll-Like Receptor 2

Grants and funding

This work was supported by a “Veni” grant (91611065) from JWH received from The Netherlands Organisation for health research and development (ZonMw). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.