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P694 Chronic cigarette smoke exposure alters the murine gut microbiome
Microbiology
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In samples with high acyl-HSL at m/z 294.2 (concentration above median), C. leptum was significantly more represented (10.22±0.07 vs 9.72±0.19 log/g of feces, P = 0.046). In these samples, there was also a trend towards higher counts in C. coccoides (P = 0.06) and lower counts in E. coli (P = 0.09). Conclusions: Our study showed for the first time that QS driven by acyl-HSLs occurs in human gut microbiota. Moreover, in IBD, acyl-HSLs profile characterized by prominent acyl-HSL at m/z 216.1 and a decrease in acyl-HSL at m/z 294.2 during flare differs from HS. The lack of this acyl-HSL was associated with low counts in Firmicutes. These results invite us to investigate acyl-HSL functional role in dysbiosis onset and in host physiology. P693 Prevalence of Clostridium perfringens infection in pediatric patients with inflammatory bowel disease: a pilot study 1
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A. Banaszkiewicz *, A. Gawronska , J. Kadzielska , I. Lazowska-Przeorek1 , K. Karolewska-Bochenek1 , P. ObuchWoszczatynski2 , D. Wultanska2 , H. Pituch2 , A. Radzikowski1 . 1 Medical University of Warsaw, Dept of Paediatric Gastroenterology and Nutrition, Warsaw, Poland, 2 Medical University of Warsaw, Dept of Medical Microbiology, Warsaw, Poland Background: Growing amount of scientific evidence suggests that superimposed infections of pathogenic bacteria may have deleterious effect on the clinical course of inflammatory bowel disease (IBD). The most important is Clostridium difficile infection the major cause of antibiotic-associated diarrhea. Clostridium perfringens infection has also been detected in up to 15% of antibiotic-associated diarrhea cases; it has not been found in healthy people. IBD patients are not routinely tested for C. perfringens toxin. The aim of the study was to investigate the prevalence of Clostridium perfringens infection in pediatric patients with IBD. Methods: It was a prospective study evaluating pediatric IBD patients in Department of Paediatric Gastroenterology and Nutrition, Warsaw, Poland. All patients were diagnosed according to Porto criteria. The severity of IBD was evaluated by determining the Pediatric Crohn’s Disease Activity Index for Crohn patients and the Pediatric Ulcerative Colitis Activity Index for ulcerative colitis patients; a PCDAI and a PUCAI score <10 were defined as a remission. Stool samples were collected at the day of admission. Clostridium difficile and Clostridium perfringens infection diagnosis was based on a positive stool enzyme immunoassays (C. difficile TOX A/B II, TechLab, Blacksburg, VA and C. perfringens enterotoxin test kit TechLab, respectively). Results: Between March 2011 and October 2012, 90 fecal specimens from patients with IBD were collected. The incidence of Clostridium perfringens infection was 9% (8/90), the incidence of Clostridium difficile infection was 23% (21/90). No specimens contained both C. difficile toxins and C. perfringens enterotoxin. Average age of patients was similar in both C. difficile and C. perfringens groups (12.7 vs. 11.7 years). There were more Crohn’s patients (6/8) in C. perfringens group than in C. difficile group (9/21). There was no statistically significant difference in the median disease activity between the C. perfringens group and C. difficile group (15.2 points vs. 13.6 points, respectively). Conclusions: The prevalence of Clostridium perfringens infection in pediatric IBD patients was 9%. Our pilot data add to the evidence base that Clostridia other than C. difficile may play a significant role in clinical IBD course, however further studies are needed to confirm this hypothesis.
P694 Chronic cigarette smoke exposure alters the murine gut microbiome L. Allais1 *, F.-M. Kerckhof2 , S. Verschuere1 , K. Bracke3 , R. De Smet1 , D. Laukens4 , M. Devos4 , N. Boon2 , G. Brusselle3 , T. Van de Wiele2 , C. Cuvelier1 . 1 Ghent University, Pathology, Faculty of Medicine & Health Sciences, Ghent, Belgium, 2 Ghent University, Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent, Belgium, 3 Ghent University, Laboratory for Translational Research in Obstructive Pulmonary diseases, Department of Respiratory Medicine, Faculty of Medicine & Health Sciences, Ghent, Belgium, 4 Ghent University, Department of Gastroenterology, Faculty of Medicine & Health Sciences, Ghent, Belgium Background: The microbiome plays a crucial role in maintaining intestinal homeostasis. Disruption of this homeostatic environment leads to destabilisation of the gut immune system and aberrant immune responses against harmless microbiota, which may be involved in the development of Crohn’s disease (CD). The most prominent environmental risk factor for CD is smoking. Therefore, the present study aims to investigate the influence of cigarette smoke on the microbiome, in particular the mucosa-adherent microbiota, and how this is linked to changes in mucin production. Methods: C57BL/6 mice were exposed to cigarette smoke (n = 6) or air (n = 6) according to a well-established protocol. After 24 weeks, the animals were sacrificed and multiple parts of the gut (ileum, proximal and distal colon) were collected. The microbial composition was analysed using denaturing gradient gel electrophoresis (DGGE) and 454 pyrosequencing. Furthermore, the expression of mucins was determined at both the mRNA level (real-time PCR) and the protein level (Alcian Blue (AB)/Periodic Acid Schiff (PAS), High Iron Diamine (HID)/ AB staining). Results: Analysis of the microbiome in smoke- and air-exposed mice revealed that the diversity of the bacterial population changed significantly after smoke exposure in all parts of the gut. In addition, the abundance of specific species, in particular Bifidobacterium sp. and Clostridium sp., tended to decrease in response to cigarette smoke in both colonic and ileal samples. A general analysis of mucin expression, using AB/PAS and HID/AB, could not demonstrate an altered expression of acidic and neutral mucins, nor changes in sulphated and sialylated mucins after cigarette smoke exposure. However, in the ileum, mRNA expression of MUC2 and MUC3 significantly increased after cigarette smoke exposure (p = 0.04 and p = 0.03 respectively). In contrast, colonic expression of MUC2 and MUC3 was unaltered, but an increased expression of MUC4 was observed (p = 0.04). Conclusions: Comparative microbial analysis in mice showed a general shift in the mucosa-adherent bacterial population, as well as specific changes in Bifidobacterium sp. and Clostridium sp., in response to cigarette smoke. In addition, smoking alters intestinal mucins, which play an important role in the gut barrier, but also in the colonization efficiency of specific gut microbiota. These findings may point to a role for altered interactions between the microbiome and intestinal mucosa contributing to the effect of smoking on intestinal homeostasis. P695 Efficacy of vaccination against hepatitis A and B in inflammatory bowel disease patients: preliminary results K. Karmiris1 *, E. Voudoukis1 , G.A. Paspatis1 . 1 Venizeleio General Hospital, Gastroenterology, Heraklion, Crete, Greece Background: Inflammatory bowel disease (IBD) patients are vulnerable to viral infections. The aim of the present study was to investigate the efficacy of vaccination against hepatitis
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In samples with high acyl-HSL at m/z 294.2 (concentration above median), C. leptum was significantly more represented (10.22±0.07 vs 9.72±0.19 log/g of feces, P = 0.046). In these samples, there was also a trend towards higher counts in C. coccoides (P = 0.06) and lower counts in E. coli (P = 0.09). Conclusions: Our study showed for the first time that QS driven by acyl-HSLs occurs in human gut microbiota. Moreover, in IBD, acyl-HSLs profile characterized by prominent acyl-HSL at m/z 216.1 and a decrease in acyl-HSL at m/z 294.2 during flare differs from HS. The lack of this acyl-HSL was associated with low counts in Firmicutes. These results invite us to investigate acyl-HSL functional role in dysbiosis onset and in host physiology. P693 Prevalence of Clostridium perfringens infection in pediatric patients with inflammatory bowel disease: a pilot study 1
1
2
A. Banaszkiewicz *, A. Gawronska , J. Kadzielska , I. Lazowska-Przeorek1 , K. Karolewska-Bochenek1 , P. ObuchWoszczatynski2 , D. Wultanska2 , H. Pituch2 , A. Radzikowski1 . 1 Medical University of Warsaw, Dept of Paediatric Gastroenterology and Nutrition, Warsaw, Poland, 2 Medical University of Warsaw, Dept of Medical Microbiology, Warsaw, Poland Background: Growing amount of scientific evidence suggests that superimposed infections of pathogenic bacteria may have deleterious effect on the clinical course of inflammatory bowel disease (IBD). The most important is Clostridium difficile infection the major cause of antibiotic-associated diarrhea. Clostridium perfringens infection has also been detected in up to 15% of antibiotic-associated diarrhea cases; it has not been found in healthy people. IBD patients are not routinely tested for C. perfringens toxin. The aim of the study was to investigate the prevalence of Clostridium perfringens infection in pediatric patients with IBD. Methods: It was a prospective study evaluating pediatric IBD patients in Department of Paediatric Gastroenterology and Nutrition, Warsaw, Poland. All patients were diagnosed according to Porto criteria. The severity of IBD was evaluated by determining the Pediatric Crohn’s Disease Activity Index for Crohn patients and the Pediatric Ulcerative Colitis Activity Index for ulcerative colitis patients; a PCDAI and a PUCAI score <10 were defined as a remission. Stool samples were collected at the day of admission. Clostridium difficile and Clostridium perfringens infection diagnosis was based on a positive stool enzyme immunoassays (C. difficile TOX A/B II, TechLab, Blacksburg, VA and C. perfringens enterotoxin test kit TechLab, respectively). Results: Between March 2011 and October 2012, 90 fecal specimens from patients with IBD were collected. The incidence of Clostridium perfringens infection was 9% (8/90), the incidence of Clostridium difficile infection was 23% (21/90). No specimens contained both C. difficile toxins and C. perfringens enterotoxin. Average age of patients was similar in both C. difficile and C. perfringens groups (12.7 vs. 11.7 years). There were more Crohn’s patients (6/8) in C. perfringens group than in C. difficile group (9/21). There was no statistically significant difference in the median disease activity between the C. perfringens group and C. difficile group (15.2 points vs. 13.6 points, respectively). Conclusions: The prevalence of Clostridium perfringens infection in pediatric IBD patients was 9%. Our pilot data add to the evidence base that Clostridia other than C. difficile may play a significant role in clinical IBD course, however further studies are needed to confirm this hypothesis.
P694 Chronic cigarette smoke exposure alters the murine gut microbiome L. Allais1 *, F.-M. Kerckhof2 , S. Verschuere1 , K. Bracke3 , R. De Smet1 , D. Laukens4 , M. Devos4 , N. Boon2 , G. Brusselle3 , T. Van de Wiele2 , C. Cuvelier1 . 1 Ghent University, Pathology, Faculty of Medicine & Health Sciences, Ghent, Belgium, 2 Ghent University, Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent, Belgium, 3 Ghent University, Laboratory for Translational Research in Obstructive Pulmonary diseases, Department of Respiratory Medicine, Faculty of Medicine & Health Sciences, Ghent, Belgium, 4 Ghent University, Department of Gastroenterology, Faculty of Medicine & Health Sciences, Ghent, Belgium Background: The microbiome plays a crucial role in maintaining intestinal homeostasis. Disruption of this homeostatic environment leads to destabilisation of the gut immune system and aberrant immune responses against harmless microbiota, which may be involved in the development of Crohn’s disease (CD). The most prominent environmental risk factor for CD is smoking. Therefore, the present study aims to investigate the influence of cigarette smoke on the microbiome, in particular the mucosa-adherent microbiota, and how this is linked to changes in mucin production. Methods: C57BL/6 mice were exposed to cigarette smoke (n = 6) or air (n = 6) according to a well-established protocol. After 24 weeks, the animals were sacrificed and multiple parts of the gut (ileum, proximal and distal colon) were collected. The microbial composition was analysed using denaturing gradient gel electrophoresis (DGGE) and 454 pyrosequencing. Furthermore, the expression of mucins was determined at both the mRNA level (real-time PCR) and the protein level (Alcian Blue (AB)/Periodic Acid Schiff (PAS), High Iron Diamine (HID)/ AB staining). Results: Analysis of the microbiome in smoke- and air-exposed mice revealed that the diversity of the bacterial population changed significantly after smoke exposure in all parts of the gut. In addition, the abundance of specific species, in particular Bifidobacterium sp. and Clostridium sp., tended to decrease in response to cigarette smoke in both colonic and ileal samples. A general analysis of mucin expression, using AB/PAS and HID/AB, could not demonstrate an altered expression of acidic and neutral mucins, nor changes in sulphated and sialylated mucins after cigarette smoke exposure. However, in the ileum, mRNA expression of MUC2 and MUC3 significantly increased after cigarette smoke exposure (p = 0.04 and p = 0.03 respectively). In contrast, colonic expression of MUC2 and MUC3 was unaltered, but an increased expression of MUC4 was observed (p = 0.04). Conclusions: Comparative microbial analysis in mice showed a general shift in the mucosa-adherent bacterial population, as well as specific changes in Bifidobacterium sp. and Clostridium sp., in response to cigarette smoke. In addition, smoking alters intestinal mucins, which play an important role in the gut barrier, but also in the colonization efficiency of specific gut microbiota. These findings may point to a role for altered interactions between the microbiome and intestinal mucosa contributing to the effect of smoking on intestinal homeostasis. P695 Efficacy of vaccination against hepatitis A and B in inflammatory bowel disease patients: preliminary results K. Karmiris1 *, E. Voudoukis1 , G.A. Paspatis1 . 1 Venizeleio General Hospital, Gastroenterology, Heraklion, Crete, Greece Background: Inflammatory bowel disease (IBD) patients are vulnerable to viral infections. The aim of the present study was to investigate the efficacy of vaccination against hepatitis