Damage/Danger Associated Molecular Patterns (DAMPs) Modulate Chlamydia pecorum and C. trachomatis Serovar E Inclusion Development In Vitro

PLoS One. 2015 Aug 6;10(8):e0134943. doi: 10.1371/journal.pone.0134943. eCollection 2015.

Abstract

Persistence, more recently termed the chlamydial stress response, is a viable but non-infectious state constituting a divergence from the characteristic chlamydial biphasic developmental cycle. Damage/danger associated molecular patterns (DAMPs) are normal intracellular components or metabolites that, when released from cells, signal cellular damage/lysis. Purine metabolite DAMPs, including extracellular ATP and adenosine, inhibit chlamydial development in a species-specific manner. Viral co-infection has been shown to reversibly abrogate Chlamydia inclusion development, suggesting persistence/chlamydial stress. Because viral infection can cause host cell DAMP release, we hypothesized DAMPs may influence chlamydial development. Therefore, we examined the effect of extracellular ATP, adenosine, and cyclic AMP exposure, at 0 and 14 hours post infection, on C. pecorum and C. trachomatis serovar E development. In the absence of de novo host protein synthesis, exposure to DAMPs immediately post or at 14 hours post infection reduced inclusion size; however, the effect was less robust upon 14 hours post infection exposure. Additionally, upon exposure to DAMPs immediately post infection, bacteria per inclusion and subsequent infectivity were reduced in both Chlamydia species. These effects were reversible, and C. pecorum exhibited more pronounced recovery from DAMP exposure. Aberrant bodies, typical in virus-induced chlamydial persistence, were absent upon DAMP exposure. In the presence of de novo host protein synthesis, exposure to DAMPs immediately post infection reduced inclusion size, but only variably modulated chlamydial infectivity. Because chlamydial infection and other infections may increase local DAMP concentrations, DAMPs may influence Chlamydia infection in vivo, particularly in the context of poly-microbial infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Bromo Cyclic Adenosine Monophosphate / pharmacology
  • Adenine / analogs & derivatives
  • Adenine / pharmacology
  • Adenosine / pharmacology*
  • Adenosine Triphosphate / pharmacology*
  • Apyrase / pharmacology
  • Benzyl Compounds / pharmacology
  • Chlamydia / drug effects*
  • Chlamydia / growth & development
  • Chlamydia / metabolism
  • Chlamydia / ultrastructure
  • Chlamydia trachomatis / drug effects*
  • Chlamydia trachomatis / growth & development
  • Chlamydia trachomatis / metabolism
  • Chlamydia trachomatis / ultrastructure
  • Cyclic AMP / pharmacology*
  • HeLa Cells
  • Host-Pathogen Interactions
  • Humans

Substances

  • Benzyl Compounds
  • erythro-(3-nonyl-p-aminobenzyl-adenine)
  • 8-Bromo Cyclic Adenosine Monophosphate
  • Adenosine Triphosphate
  • Cyclic AMP
  • Apyrase
  • Adenine
  • Adenosine

Grants and funding

This work was supported by 310030_147026, www.snf.ch. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.