Typing of feces-derived Candida albicans strains using a novel seven-locus microsatellite panel reveals associations with yeast phenotype in individuals with inflammatory bowel disease.

Abstract

Inflammatory diseases of the human gastrointestinal tract are affected by the microbes that reside in the mucosal surfaces. Patients with inflammatory bowel diseases (IBD) have altered bacterial and fungal intestinal compositions, including higher levels of fecal Candida yeasts. Ongoing research indicates that genetic and phenotypic diversity of Candida albicans may be linked with disease severity. Here, we set out to investigate feces-derived C. albicans strains from individuals with IBD and healthy volunteers through microsatellite-based genotyping and phenotypic assays. A seven-locus microsatellite panel was applied, of which six loci were newly developed. It appears that there is no specific lineage of C. albicans that is associated with IBD, but rather that the three study populations (Crohn's disease, ulcerative colitis, healthy volunteers) do have distinguishable distributions of genotypes. In addition, phenotypic characterization by means of enzyme release assays revealed trends between genotypes, virulence-related enzyme activity and clinical biomarkers. We thus show that microsatellite typing can describe genetic diversity of feces-derived C. albicans strains, and that phenotypic diversity of these strains may indeed correlate with fungal genotype or disease. This study opens further possibilities to investigate fecal fungi in relation to severity of inflammation in IBD or in other (intestinal) diseases.