Factors affecting the in-vitro adherence of the fungal oral pathogen Candida albicans to epithelial cells of human origin.

An in-vitro technique was used to investigate the effects of oral commensal bacteria, serum, saliva, germ-tube formation and pH on the adherence of two strains of C. albicans to HeLa cells. Streptococcus salivarius and Streptococcus mitior reduced candidal adhesion whereas Streptococcus mutans had no significant effect. A mixed salivary pellicle on HeLa cells significantly enhanced candidal adhesion and a serum layer had no effect. Yeasts pre-incubated in whole saliva for 3 h showed significantly greater adhesion to HeLa and human embryonic kidney epithelial cells than yeasts in phosphate-buffered saline. The adherence of hyphal phase candida was significantly greater than in the blastospore phase. Adhesion varied with the pH of the test medium, maximal adherence was at pH 3 with less under neutral pH conditions. The factors involved in the adhesion of C. albicans to epithelial surfaces are complex and may play a rôle in the aetiopathology of human mucosal candidoses.