P696. Terminal restriction fragment length polymorphism (TRFLP) analysis of mucosa-associated microbiota of patients with ulcerative colitis in southwest China
W. Ran1, O. Qin1, 1Sichuan University, The Department of Gastroenterology of West China hospital of Sichuan University, Chendu, China
Recently more and more findings indicate that an imbalance in normal gut biota plays an important role in the pathogenesis of ulcerative colitis (UC). The objective of the study was to investigate the potential differences in the intestinal microbiota between UC patients and healthy control subjects in southwest China, using terminal restriction fragment length polymorphism (T-RFLP) analysis of the mucosa-associated microbiota.
All the people involved in the experiment were grouped into 3 subgroups. 29 in active UC group (A-UC), 21 in non-active UC group (NA-UC) and 23 in healthy controls group. Mucosa-associated microbiota was compared between healthy controls and UC patients using T-RFLP analysis. Microbiota in both the active and inactive phase was also compared in sub-group analysis.
Cluster analysis shows a clear distinction between UC patient group and healthy control group, and subjects in the same sub-group show significant similarity than people in different sub-group. Cluster analysis also shows patient in UC group with the near or same Baron index score can be grouped into same sub-cluster. Compared to health controls group, Richness and Shannon-Wiener index increased in NA-UC. However Richness and Shannon-Wiener index decreased in A-UC. Compared to active UC patients, both Shannon-Wiener index and Richness increased in the NA-UC. With MspI enzyme, compared to healthy control group, the unique dominate terminal-restriction fragment in UC group were 214bp, 221bp, 281bp; 37bp and 96bp, 281bp were unique dominate terminal-fragments in non-active group and A-UC respectively. After reference to the MiCA database, the dominant bacteria in healthy controls group were composed by phylum Firmicutes, phylum Bacteroidetes, phylum Proteobacteria and uncultured bacteria; in UC group by phylum Firmicutes, phylum Bacteroidetes, phylum Actinobacteria, phylum Acidobacteria, phylum Proteobacteria. Compared to NA-UC, bacteria such as Bacteroides sp., uncultured Lactobacillus sp., uncultured Actinobacterium, uncultured alpha Proteobacterium reduced and phylum Bacteroidetes were the most obvious; phylum Firmicutes such as uncultured Firmicutes bacteria, Clostridium sp. and uncultured beta Proteobacterium, uncultured bacterium increased.
The T-RFLP profile of UC patient were significant different from healthy controls. Biodiversity reduced in A-UC and increased in NA-UC. Bacterial dysbiosis may play an important role in the pathogenesis of UC.