Salivary anti-candidal assays

Area of Science:

• Oral microbiology
• Immunology
• Antimicrobial research

Background:

• Candida albicans is an opportunistic fungal pathogen.
• Saliva contains antimicrobial components with potential antifungal activity.
• Directly assaying saliva's antifungal effect on Candida albicans viability is challenging.

Purpose of the Study:

• To determine the antifungal activity of human saliva against Candida albicans blastospores.
• To optimize methods for quantifying salivary antifungal effects.
• To investigate the impact of pH and cell concentration on antifungal activity.

Main Methods:

• Pre-incubation of Candida albicans with parotid, submandibular-sublingual, and whole salivas.
• Assessing blastospore viability and germ tube formation after saliva treatment.
• Utilizing acidification, boiling, and buffer resuspension for accurate quantification.
• Evaluating antifungal activity at various yeast cell concentrations and pH levels.

Main Results:

• Direct viability assays were unsuccessful; pre-incubation and specific treatments were required.
• Acidification and boiling improved reproducibility of antifungal activity measurements.
• Inhibition of germ tube formation was detectable directly in saliva, unlike viability.
• Antifungal effects on division were minimal above 10^6 CFU/ml and pH-independent.
• Germ tube formation inhibition was significant at pH 5.

Conclusions:

• Specific pre-treatment methods are essential for accurate assessment of salivary antifungal activity against Candida albicans.
• Saliva possesses antifungal components, but their bioavailability may be limited.
• Further research into salivary antifungal mechanisms in health and disease is warranted.