Ribosomal DNA sequence analysis of mucosa-associated bacteria in Crohn's disease
Article first published online: 14 DEC 2006
Copyright © 2004 Crohn's & Colitis Foundation of America, Inc.
Inflammatory Bowel Diseases
Volume 10, Issue 6, pages 824–833, November 2004
How to Cite
Prindiville, T., Cantrell, M. and Wilson, K. H. (2004), Ribosomal DNA sequence analysis of mucosa-associated bacteria in Crohn's disease. Inflamm Bowel Dis, 10: 824–833. doi: 10.1097/00054725-200411000-00017
- Issue published online: 14 DEC 2006
- Article first published online: 14 DEC 2006
- Manuscript Accepted: 30 JUN 2004
- Manuscript Received: 16 DEC 2003
- Department of Veterans Affairs. Grant Number: NIH KD35747-18
- Crohn's disease;
- inflammatory bowel disease;
- microbial ecology;
- ribosomal DNA;
- intestinal microbiology
Enteric bacteria are implicated in the pathogenesis of Crohn's disease (CD); however, no specific causative organisms have been identified.
This study was undertaken to correlate disease activity with changes in intestinal biota in patients with CD.
Ribosomal DNA analysis was used to explore the composition of the intestinal biota in patients with (1) CD undergoing colonoscopy, (2) CD undergoing surgical resection, and (3) no inflammatory bowel disease.
Primers targeting bacterial 16S ribosomal DNA (rDNA) were used to amplify bacterial DNA associated with active CD lesions, comparable normal tissue from patients with CD, and normal control tissue. Each amplicon was cloned. Seven hundred thirty-nine rDNA clones were sequenced from 16 biopsies from CD patients, 15 surgical samples, and 10 biopsies from normal control patients.
Known extracellular or intracellular pathogens were not found. No rDNA sequence, phylogenetic group, or subgroup was consistently associated with CD lesions compared with normal tissues from the same patients. Colonic biopsies from CD-afflicted patients compared with biopsies from normal control subjects had an increase in facultative bacteria; in small bowel, CD patients had an increase in the Ruminococcus gnavus subgroup with a decrease in the Clostridium leptum and Prevotella nigrescens subgroups. However, differences in small bowel may have reflected individual variation rather than disease association. Surgical samples showed differences when compared with biopsy-derived samples.
These findings suggest that CD is not caused by invasive pathogens associated specifically with the sites of lesions but that dysbiosis exists in this condition.