title: Adhesion of Candida albicans to epithelial cells effect of polyoxin D.
abstract: Data from our previous studies suggested that the fungal cell wall component, chitin, is involved in the adhesion of Candida albicans to mucosal surfaces. In the present study, we investigated the effect of polyoxin D, an inhibitor of chitin synthase, on the interaction of the fungus with epithelial cells. The effect of polyoxin D on Candida was evaluated in in vitro assays for its capacity to adhere to buccal epithelial cells (BEC), and by fluorescent-microscopy photometry and flow cytometry using cells stained with cellufluor (CF), a fluorochrome with affinity for chitin. C. albicans grown with and without polyoxin D was stained with CF and examined in a fluorescent microscope equipped with a photometer. Measurements of fluorescence revealed a wide range of intensity among C. albicans cells and a decreased intensity in polyoxin D treated cultures. Flow cytometry analyses of yeasts revealed 2 peaks of fluorescence intensity, and pointed to differences between polyoxin D treated and non-treated microorganisms. C. albicans stained with CF were separated into 2 subpopulations by flow cytometry according to fluorescence intensity. In vitro adhesion of each subpopulation to BEC was similar. Polyoxin D treated fungi showed significantly reduced adherence to BEC, as evaluated by a radioactivity assay with radiolabelled yeasts and by microscopic readings. The reduction in adhesion was Polyoxin D concentration dependent. These observations support our previous findings suggesting involvement of chitin in the attachment process of C. albicans (CBS562) to epithelial cells.
authors.affiliation: Department of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Gottlieb
authors.forename: Z
authors.initials: Z
authors.lastname: Altboum
authors.forename: D C
authors.initials: DC
authors.lastname: Savage
authors.forename: E
authors.initials: E
authors.lastname: Segal
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects / Q000378:metabolism*; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D002686:Chitin / Q000378:metabolism; D002687:Chitin Synthase / Q000037:antagonists & inhibitors; D004847:Epithelial Cells; D004848:Epithelium / Q000382:microbiology; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D006801:Humans; D008856:Microscopy, Fluorescence; D009061:Mouth Mucosa / Q000166:cytology / Q000382:microbiology*; D009930:Organic Chemicals; D010783:Photometry; D011741:Pyrimidine Nucleosides / Q000494:pharmacology
chemical_list: D000935:Antifungal Agents; D005456:Fluorescent Dyes; D009930:Organic Chemicals; D011741:Pyrimidine Nucleosides; D002686:Chitin; C048787:cellufluor; C002458:polyoxorim; D002687:Chitin Synthase