Modulation of Candida albicans virulence in in vitro biofilms by oral bacteria

Candida‐associated denture stomatitis presents as erythema of the palatal mucosa and is caused by biofilms containing the fungus Candida albicans that co‐reside with oral bacteria on the denture‐fitting surface. This study aimed to assess the effect of several frequently encountered oral bacteria on the expression of Candida albicans virulence factors in in vitro polymicrobial biofilms. Biofilms containing C. albicans and selected bacterial species were grown on denture‐acrylic, and analysed by microscopy and by qPCR for expression of putative virulence genes. Candida albicans‐only biofilms showed limited hyphal production. Hyphal development was significantly (P<0·001) increased when biofilms also contained 4 species of oral bacteria (Streptococcus sanguinis, S. gordonii, Actinomyces odontolyticus, and A. viscosus), as was the expression of virulence genes (P<0·05). Importantly, inclusion of Porphyromonas gingivalis in the biofilm consortium resulted in significant (P