Analysis of Escherichia coli Isolated from Patients Affected by Crohn’s Disease
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The etiopathogenesis of Crohn’s disease (CD) is still controversial: several genetic, immunologic, and environmental factors, including some bacteria, have been implicated. This study has been devised to assess the involvement of Escherichia coli in CD. Seven E. coli strains were isolated from 14 biopsies obtained from ileocolic ulcers of patients affected by inflammatory bowel disease (IBD), including six with ulcerative colitis and eight with CD. Five strains, exclusively isolated from CD patients, were found inside mucosal cells. Different PCR techniques (for chuA, yjaA, TspE4.C2, escV, and bfpB genes) were performed and PFGE was carried out to characterize these bacteria in comparison with other E. coli strains isolated from non-IBD specimens. The correlation of these characters with bacterial invasiveness on intestinal (Caco-2) and phagocytic (U937) cells was assessed. Overall our pilot data suggest that five among eight strains isolated from CD patients belonged to the adherent-invasive E. coli (AIEC) group, and were invasive on Caco-2 cells and resistant to phagocytosis. These findings suggest that these bacteria could be considered target organisms whose elimination could reduce the intestinal inflammatory process and CD progression.
KeywordsInflammatory Bowel Disease Ulcerative Colitis Irritable Bowel Syndrome Confocal Laser Endomicroscopy Bioptic Specimen
This study was partly supported by a grant from Piedmont Region (2008 bis).
- 4.Baumgart M, Dogan B, Rishniw M, Weitzman G, Bosworth B, Yantiss R, Orsi RH, Wiedemann M et al (2007) Culture independent analysis of ileal mucosa reveals a selective increase in invasive Escherichia coli of novel phylogeny relative to depletion of Clostridiales in Crohn’s disease involving the ileum. ISME J 1:403–418PubMedCrossRefGoogle Scholar
- 7.CDCPulseNetUSA (2004) One-day (24–28 h) standardized laboratory protocol for molecular subtyping of Escherichia coli O157:H7, non-typhoidal Salmonella serotypes, and Shigella sonnei by pulsed field gel electrophoresis (PFGE). PulseNet PFGE Manual 5.1–5.3:1–13Google Scholar
- 12.Dice L (1945) Measures of the amount of ecological association between species. Ecology (New York) 26:297–302Google Scholar
- 22.Martinez-Medina M, Aldeguer X, Lopez-Siles M, Gonzalez-Huix F, Lopez-Oliu C, Dahbi G, Blanco JE, Blanco J, Garcia-Gil LJ, Darfeuille-Michaud A (2009) Molecular diversity of Escherichia coli in the human gut: new ecological evidence supporting the role of adherent-invasive E. coli (AIEC) in Crohn’s disease. Inflam Bowel Dis 15:872–882CrossRefGoogle Scholar
- 23.Martinez-Medina M, Mora A, Blanco M, Lopez C, Alonso MP, Bonacorsi S, Nicolas-Chanoine MH, Darfeuille-Michaud A, Garcia-Gil J, Blanco J (2009) Similarity and divergence among adherent-invasive E. coli (AIEC) and extraintestinal pathogenic E. coli (ExPEC). J Clin Microbiol 47:3968–3979PubMedCrossRefGoogle Scholar
- 24.Moussata D, Goetz M, Gloeckner A, Kerner M, Campbell B, Hoffman A, Biesterfeld S, Flourie B, Saurin J-C, Galle PR, Neurath MF, Watson AJM, Kiesslich R (2011) Confocal laser endomicroscopy is a new imaging modality for recognition of intramucosal bacteria in onflammatory bowel disease in vivo. Gut 60:26–33PubMedCrossRefGoogle Scholar
- 25.Muller D, Hagedorn P, Brast S, Heusipp G, Bielaszewska M, Friedrich A, Karch H, Schmidt MA (2006) Rapid identification and differentiation of clinical isolates of enteropathogenic Escherichia coli (EPEC), and Shiga toxin-producing Escherichia coli by one-step multiplex PCR method. J Clin Microbiol 44:2626–2629PubMedCrossRefGoogle Scholar