A cell impedance-based real-time in vitro assay to assess the toxicity of amphotericin B formulations

Toxicol Appl Pharmacol. 2017 Nov 1:334:18-23. doi: 10.1016/j.taap.2017.08.017. Epub 2017 Sep 1.

Abstract

Aerosolized liposomal amphotericin B (L-AmB) has been investigated as prophylaxis against invasive aspergillosis. However, the clinical results are controversial and some trials suggest that toxicity could be a limitation for wider use. Our aim was to assess the dynamics of cell toxicity induced in a human alveolar epithelial cell line (A549) after exposure to L-AmB (50 to 400μg/ml) or amphotericin B deoxycholate (D-AmB; 50 to 200μg/ml) by monitoring real-time A549 cell viability using an impedance-based technology. Results were expressed as cell index values integrating cell adhesion, proliferation, and survival. In parallel, the gene expression of proinflammatory cytokines was quantified at 6 and 24h after drug addition by real-time RT-PCR on cell lysates. No sustained reduction of cell indexes was observed with L-AmB or empty liposomes, even at 400μg/ml. Only the highest concentration tested of L-AmB (400μg/ml) yielded transient significant 6-fold and 4-fold induction of TNF-α and IL-8 mRNAs, respectively. In contrast, D-AmB induced a decrease in cell indexes and only the 50μg/ml concentration of D-AmB was followed by cell recovery, higher concentrations leading to cell death. Significant 4-fold, 7-fold and 3-fold inductions of TNF-α, IL-8 and IL-33 mRNAs were also observed at 6h with 50μg/ml of D-AmB. In conclusion, continuous cell impedance measurement showed no toxicity on overall cellular behavior although a slight proinflammatory cytokine expression is possible after L-AmB challenge. Real-time kinetics of cell impedance is an interesting tool for initial screening of cell toxicity.

Keywords: Cell impedance; Gene expression; In vitro assay; Liposomal amphotericin B; Proinflammatory cytokines; Real-time.

MeSH terms

  • A549 Cells
  • Aerosols / toxicity*
  • Amphotericin B / chemistry
  • Amphotericin B / toxicity*
  • Antifungal Agents / chemistry
  • Antifungal Agents / toxicity*
  • Cell Adhesion / drug effects
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Cytokines / genetics
  • Cytokines / metabolism
  • Deoxycholic Acid / toxicity*
  • Dosage Forms
  • Drug Combinations
  • Electric Impedance*
  • Epithelial Cells / drug effects*
  • Gene Expression Regulation / drug effects
  • Humans

Substances

  • Aerosols
  • Antifungal Agents
  • Cytokines
  • Dosage Forms
  • Drug Combinations
  • liposomal amphotericin B
  • Deoxycholic Acid
  • Amphotericin B
  • amphotericin B, deoxycholate drug combination