Adherence on buccal epithelial cells and germ tube formation in the continuous flow culture of clinical Candida albicans isolates.

Mucosal adherence and germ tube formation have been considered as important virulence factors of Candida albicans. We investigated 11 clinical isolates (among them six isolates from oesophageal thrush) for quantification of adherence to buccal epithelial cells and germ tube formation in the continuous flow culture in vitro, and correlated the results with the clinical data of the patients. Adherence varied considerably between the different C. albicans strains. Strains recovered from clinically, culturally and serologically confirmed oesophageal thrush adhered stronger to buccal epithelial cells. Isolates from cases with heavy colonisation but clinically without candidosis were less adherent. Only after 30 min germ tube formation was observed in the continuous flow culture. Strains with stronger adherence also showed significantly faster and increased germ tube formation. The patients with oesophageal thrush did not suffer any particular immunosuppression such as HIV infection, although in most cases chronic alcoholism was apparent. We conclude, that in cases with minor immunosuppression the expression of the virulence factors adherence and germ tube formation plays an important role in the pathogenesis of candidosis, whereas it may be of less importance in cases with severe immunosuppression. In the latter they may, however, influence outcome.