Adhesion of Candida albicans to epithelial cells: Effect of antimycotics

AIM. Adhesion of Candida albicans to host cells is considered an initial step in the development of infection. The aim of this study was to explore the effect of sub-inhibitory concentrations of antifungal drugs on fungal adhesion. Materials and methods. Towards this end the effect of two antifungals with different modes of action was examined: bifonazole (BZ), which interfers in the ergosterol synthesis and 5-fluorocytosine (5-FC), which affects nucleic acid synthesis. C. albicans was grown in the presence of sub-MIG (minimal inhibitory concentrations) of BZ and 5-FC. The in vitro adhesion to human buccal epithelial cells (BEG) of yeasts exposed to BZ or 5-FC was evaluated in comparison to controls. In addition, ultrastructural observations by scanning electron microscopy (SEM) were carried out. Results. The results revealed that C. albicans grown at 1/2, 1/3, 1/4 MIC of BZ had a reduced adhesion level, revealed structural changes and changes in the interaction with BEC as noted by SEM. Yeasts grown in the presence of the same concentrations of 5-FC did not exhibit reduced adhesion, and although structural changes were noted, the interaction with BEC was almost not affected. The results indicated that BZ, which affects cell-membrane integrity and thereby possibly also membrane-bound enzymes such as chitin synthase, involved in chitin synthesis, affects also adhesion. Conclusion. The present study strengthens findings from previous studies, which indicated involvement of chitin in adhesion of C. albicans to host cells.