Project: Investigate the relationship between bacteria and fungi in the gut, and whether fungi plays a role in causing Crohn’s
Year: 2015 – IN PROGRESS
Researcher: Professor Chris Probert, University of Liverpool
The aetiology of Crohn’s disease (CD) remains unknown. A common view is that it arises from an abnormal immune response to an environmental factor in a genetically predisposed individual. Fungi are also part of the intestinal microbiome, but they have received little attention. Anti-Saccharomyces cerevisiae antibodies (ASCA) are associated with small bowel Crohn’s disease. The target epitope for ASCA is a mannan shared with Candida. Fungi are the main source of octen-3-ol which we have reported in the volatile organic compounds (VOCs) emitted from faeces of patients with IBD. Recently, we have found it in 26/62 patients with active CD compared with 7/109 controls. These data suggest an association between intestinal fungi and IBD.
We will investigate the hypothesis that specific intestinal fungi, present in CD, lead to bacterial dysbiosis by inhibition of specific phyla of bacteria and inhibit killing of intra-macrophage E. coli. If validated, this work will lead to new treatment options for CD.
We propose that:
i) changes the faecal mycobiome are associated with CD
ii) these changes may impact on the bacterial microbiome
iii) and may also suppress phagocytic killing of bacteria including AIEC via mannan release