Competitive fungal commensalism mitigates candidiasis pathology

Area of Science:

• Microbiology
• Mycology
• Immunology

Background:

• The gut mycobiota's role in host health is not fully understood.
• Commensal fungi interactions with the host and their functions require further investigation.

Purpose of the Study:

• To identify novel fungal commensals in the gut microbiome.
• To investigate the functional role of these commensals in host-pathogen interactions, specifically concerning Candida albicans.

Main Methods:

• Isolation and identification of a new fungal species from murine intestines.
• Experimental exposure of mice to the identified fungus.
• Assessment of colonization resistance against Candida albicans.
• Metagenomic analysis of human commensal samples.

Main Results:

• A new fungal commensal, Kazachstania heterogenica var. weizmannii, was identified in murine intestines.
• K. weizmannii significantly reduced Candida albicans colonization and burden in mice.
• This fungal commensalism mitigated fatal candidiasis in immunosuppressed mice.
• K. heterogenica or K. weizmannii were detected in human commensal samples.

Conclusions:

• Competitive fungal commensalism exists within the intestinal microbiota, independent of bacterial or immune factors.
• Kazachstania weizmannii demonstrates potential therapeutic value for managing Candida albicans-related diseases.