AmBisome and Amphotericin B inhibit the initial adherence of Candida albicans to human epithelial cell lines, but do not cause yeast detachment.
BACKGROUND
Candida biofilms with reduced susceptibility to conventional antifungals are sensitive to lipid formulations of amphotericin B (AMB). We examined the effect of the liposomal AMB formulation, AmBisome, and free AMB on the adherence of C. albicans to HeLa cervical carcinoma and HSC-3 oral squamous cell carcinoma cells.


METHODS
HeLa and HSC-3 cells were incubated with three oral isolates of C. albicans either in the presence of AmBisome or AMB, or pre-incubated with yeasts and subsequently exposed to the drug. The effect of the drugs on the viability of HeLa and HSC-3 cells was determined by an Alamar Blue assay.


RESULTS
Following a 1-h incubation in the presence of AmBisome, at 1-256 microg/ml, the adherence of C. albicans to HeLa and HSC-3 cells was reduced considerably. For example at 16 microg/ml, adherence was diminished by approximately 66% in HeLa and by approximately 36% in HSC-3 cells. The susceptibility of cell-associated Candida to antifungals was decreased markedly. The reduction in adherence was between 3.3 and 13.7%, when compared to the drug-free controls. AmBisome was not toxic in the range 1-256 microg/ml, while free AMB was not toxic at 1 and 4 microg/ml to HeLa cells and at 1, 4 and 16 microg/ml to HSC-3 cells.


CONCLUSIONS
AmBisome inhibited candidal attachment when present during the "adherence phase" but did not cause detachment of cell-associated yeasts. The effect of AmBisome on candidal adherence to HSC-3 cells was less inhibitory than that observed with HeLa cells. Candidal adherence to epithelial cells is significantly reduced when antifungal polyenes are present during the "adherence phase", while cell-associated Candida is resistant to antifungals in terms of adherence.
Dorocka-Bobkowska
Barbara
B
Department of Prosthodontics, K. Marcinkowski University of Medical Sciences, Poznań, Poland.
Düzgüneş
Nejat
N
Konopka
Krystyna
K
D000666:Amphotericin B / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D018441:Biofilms; D002176:Candida albicans / Q000187:drug effects / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004847:Epithelial Cells / Q000382:microbiology*; D006801:Humans
D000935:Antifungal Agents; C068538:liposomal amphotericin B; D000666:Amphotericin B