AmBisome inhibits the adherence of Candida albicans to HeLa cells
Nejat Düzgüneş: 0000-0001-6159-1391
82nd General Session of the International Association for Dental Research and 33rd Annual Meeting of the American Association for Dental Research
March 10-13, 2004
Date of Presentation
Journal of Dental Research
Journal Volume Number
Objectives: Candidal adherence to epithelial cells is significantly reduced when antifungal polyenes are present during the “adherence phase”, but the treatment does not result in detachment of cell-associated yeasts. It has been reported that Candida biofilms with reduced susceptibility to conventional antifungals, are sensitive to lipid formulations of amphotericin B (AMB). Here we examined the effect of AmBisome, the liposomal AMB formulation, and free AMB on the adherence of C. albicans to HeLa cells. Methods: The adherence of C. albicans to HeLa cells was determined as described by Samaranayake et al. (1994). Cells were either incubated with Candida in the presence of the drug or pre-incubated with yeasts for 1 hr at 37°C and subsequently exposed to the drug. The cytotoxic effect of the drugs on HeLa cells was determined by an Alamar Blue assay. Results: AmBisome was not toxic in the range 1 – 256 µg/ml, while AMB was toxic above 4 µg/ml. Following the 1 hr incubation, in the presence of AMB at 1 and 4 µg/ml, the adherence of C. albicans was reduced by 58 and 71%, respectively. Under these conditions, AmBisome at 1, 4, 16, 64 and 256 µg/ml reduced adherence by 54, 63, 70, 76, and 83%, respectively. These values were significantly different from the controls (P < 0.0005). The susceptibility of cell-associated Candida to AMB and AmBisome was significantly lower. The reduction in adherence was between 4 and 10%, when compared to the drug-free controls. The values obtained for AmBisome at 16, 64 and 256 µg/ml were significantly different from the controls (P < 0.05). Conclusions: The liposomal AMB formulation, AmBisome, which is not toxic in a wide range of concentrations, inhibits candidal colonization when present during the “adherence phase”, while the cell-associated Candida yeasts are highly resistant to antifungals in terms of adherence.
AmBisome inhibits the adherence of Candida albicans to HeLa cells.
Paper presented at 82nd General Session of the International Association for Dental Research and 33rd Annual Meeting of the American Association for Dental Research in Honolulu, HI.