Synergistic effect between amoxicillin and TLR ligands on dendritic cells from amoxicillin-delayed allergic patients

PLoS One. 2013 Sep 16;8(9):e74198. doi: 10.1371/journal.pone.0074198. eCollection 2013.

Abstract

Amoxicillin, a low-molecular-weight compound, is able to interact with dendritic cells inducing semi-maturation in vitro. Specific antigens and TLR ligands can synergistically interact with dendritic cells (DC), leading to complete maturation and more efficient T-cell stimulation. The aim of the study was to evaluate the synergistic effect of amoxicillin and the TLR2, 4 and 7/8 agonists (PAM, LPS and R848, respectively) in TLR expression, DC maturation and specific T-cell response in patients with delayed-type hypersensitivity (DTH) reactions to amoxicillin. Monocyte-derived DC from 15 patients with DTH to amoxicillin and 15 controls were cultured with amoxicillin in the presence or absence of TLR2, 4 and 7/8 agonists (PAM, LPS and R848, respectively). We studied TLR1-9 gene expression by RT-qPCR, and DC maturation, lymphocyte proliferation and cytokine production by flow cytometry. DC from both patients and controls expressed all TLRs except TLR9. The amoxicillin plus TLR2/4 or TLR7/8 ligands showed significant differences, mainly in patients: AX+PAM+LPS induced a decrease in TLR2 and AX+R848 in TLR2, 4, 7 and 8 mRNA levels. AX+PAM+LPS significantly increased the percentage of maturation in patients (75%) vs. controls (40%) (p=0.036) and T-cell proliferation (80.7% vs. 27.3% of cases; p=0.001). Moreover, the combinations AX+PAM+LPS and AX+R848 produced a significant increase in IL-12p70 during both DC maturation and T-cell proliferation. These results indicate that in amoxicillin-induced maculopapular exanthema, the presence of different TLR agonists could be critical for the induction of the innate and adaptive immune responses and this should be taken into account when evaluating allergic reactions to these drugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Amoxicillin / pharmacology
  • Amoxicillin / therapeutic use*
  • Cells, Cultured
  • Cytokines / pharmacology
  • Dendritic Cells / cytology
  • Dendritic Cells / drug effects
  • Drug Eruptions / etiology
  • Female
  • Humans
  • Hypersensitivity / drug therapy*
  • Hypersensitivity / metabolism*
  • Imidazoles / pharmacology
  • Imidazoles / therapeutic use
  • Male
  • Middle Aged
  • Monocytes / cytology
  • Monocytes / drug effects
  • Toll-Like Receptor 2 / agonists
  • Toll-Like Receptor 2 / metabolism

Substances

  • Cytokines
  • Imidazoles
  • TLR2 protein, human
  • Toll-Like Receptor 2
  • Amoxicillin
  • resiquimod

Grants and funding

This work was supported by grants from: the Carlos III (ISCIII PS09/00966, PI12/02481 and PI12/02529), Junta de Andalucía (PI-0199/2007, PI-0180/2008, CTS-7433 and CTS 06603), and FIS-Thematic Networks and Co-operative Research Centres: RIRAAF (RD07/0064; RD12/0013). The BBSSPA, Carlos Haya Hospital Unit is supported by Instituto de Salud Carlos III, Spanish Health Ministry (Grant nº RD09/0076/00112)” and the board of health ministry of Andalusia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.