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Balfour R Sartor - One of the best experts on this subject based on the ideXlab platform.
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Mouse Background Strain Profoundly Influences Paneth Cell Function and Intestinal Microbial Composition
2016Co-Authors: Ajay S Gulati, Janelle C Arthur, Emily Grossniklaus, Lieselotte S M Kreuk, Susan J Henning, Michael T. Shanahan, Richard J. Von, Balfour R SartorAbstract:Background: Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota. Methodology and Principal Findings: Paneth cell numbers were determined by flow cytometry. AntiMicrobial peptide (AMP) expression was evaluated using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), acid urea-polyacrylamide gel electrophoresis, and mass spectrometry. Effects of mouse background on Microbial Composition were assessed by reciprocal colonization of germ-free mice from both background strains, followed by Compositional analysis of resultant gut bacterial communities using terminal restriction fragment length polymorphism analysis and 16 S qPCR. Our results revealed that 129/SvEv mice possessed fewer Paneth cells and a divergent AMP profile relative to C57BL/
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mouse paneth cell antiMicrobial function is independent of nod2
Gut, 2014Co-Authors: Michael J Shanahan, Emily Grossniklaus, Richard J Von Furstenberg, Susan J Henning, Balfour R Sartor, Ian M Carroll, Andrew M White, Roshonda Barner, Anthony A Fodor, Ajay S GulatiAbstract:Objective Although polymorphisms of the NOD2 gene predispose to the development of ileal Crohn9s disease, the precise mechanisms of this increased susceptibility remain unclear. Previous work has shown that transcript expression of the Paneth cell (PC) antiMicrobial peptides (AMPs) α-defensin 4 and α-defensin-related sequence 10 are selectively decreased in Nod2 −/− mice. However, the specific mouse background used in this previous study is unclear. In light of recent evidence suggesting that mouse strain strongly influences PC antiMicrobial activity, we sought to characterise PC AMP function in commercially available Nod2 −/− mice on a C57BL/6 (B6) background. Specifically, we hypothesised that Nod2 −/− B6 mice would display reduced AMP expression and activity. Design Wild-type (WT) and Nod2 −/− B6 ileal AMP expression was assessed via real-time PCR, acid urea polyacrylamide gel electrophoresis and mass spectrometry. PCs were enumerated using flow cytometry. Functionally, α-defensin bactericidal activity was evaluated using a gel-overlay antiMicrobial assay. Faecal Microbial Composition was determined using 454-sequencing of the bacterial 16S gene in cohoused WT and Nod2 −/− littermates. Results WT and Nod2 −/− B6 mice displayed similar PC AMP expression patterns, equivalent α-defensin profiles, and identical antiMicrobial activity against commensal and pathogenic bacterial strains. Furthermore, minimal differences in gut Microbial Composition were detected between the two cohoused, littermate mouse groups. Conclusions Our data reveal that Nod2 does not directly regulate PC antiMicrobial activity in B6 mice. Moreover, we demonstrate that previously reported Nod2-dependent influences on gut Microbial Composition may be overcome by environmental factors, such as cohousing with WT littermates.
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inflammatory bowel diseases phenotype c difficile and nod2 genotype are associated with shifts in human ileum associated Microbial Composition
PLOS ONE, 2012Co-Authors: Christina M Hamm, Ajay S Gulati, Balfour R Sartor, Hongyan Chen, Tianyi Zhang, James F Rohlf, Wei Zhu, Charles E Robertson, Norman R Pace, Edgar C BoedekerAbstract:We tested the hypothesis that Crohn’s disease (CD)-related genetic polymorphisms involved in host innate immunity are associated with shifts in human ileum–associated Microbial Composition in a cross-sectional analysis of human ileal samples. Sanger sequencing of the bacterial 16S ribosomal RNA (rRNA) gene and 454 sequencing of 16S rRNA gene hypervariable regions (V1–V3 and V3–V5), were conducted on macroscopically disease-unaffected ileal biopsies collected from 52 ileal CD, 58 ulcerative colitis and 60 control patients without inflammatory bowel diseases (IBD) undergoing initial surgical resection. These subjects also were genotyped for the three major NOD2 risk alleles (Leu1007fs, R708W, G908R) and the ATG16L1 risk allele (T300A). The samples were linked to clinical metadata, including body mass index, smoking status and Clostridia difficile infection. The sequences were classified into seven phyla/subphyla categories using the Naive Bayesian Classifier of the Ribosome Database Project. Centered log ratio transformation of six predominant categories was included as the dependent variable in the permutation based MANCOVA for the overall Composition with stepwise variable selection. Polymerase chain reaction (PCR) assays were conducted to measure the relative frequencies of the Clostridium coccoides – Eubacterium rectales group and the Faecalibacterium prausnitzii spp. Empiric logit transformations of the relative frequencies of these two Microbial groups were included in permutation-based ANCOVA. Regardless of sequencing method, IBD phenotype, Clostridia difficile and NOD2 genotype were selected as associated (FDR ≤0.05) with shifts in overall Microbial Composition. IBD phenotype and NOD2 genotype were also selected as associated with shifts in the relative frequency of the C. coccoides – E. rectales group. IBD phenotype, smoking and IBD medications were selected as associated with shifts in the relative frequency of F. prausnitzii spp. These results indicate that the effects of genetic and environmental factors on IBD are mediated at least in part by the enteric microbiota.
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mouse background strain profoundly influences paneth cell function and intestinal Microbial Composition
PLOS ONE, 2012Co-Authors: Ajay S Gulati, Michael J Shanahan, Janelle C Arthur, Emily Grossniklaus, Richard J Von Furstenberg, Lieselotte S M Kreuk, Susan J Henning, Christian Jobin, Balfour R SartorAbstract:Background Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota.
Ajay S Gulati - One of the best experts on this subject based on the ideXlab platform.
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Mouse Background Strain Profoundly Influences Paneth Cell Function and Intestinal Microbial Composition
2016Co-Authors: Ajay S Gulati, Janelle C Arthur, Emily Grossniklaus, Lieselotte S M Kreuk, Susan J Henning, Michael T. Shanahan, Richard J. Von, Balfour R SartorAbstract:Background: Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota. Methodology and Principal Findings: Paneth cell numbers were determined by flow cytometry. AntiMicrobial peptide (AMP) expression was evaluated using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), acid urea-polyacrylamide gel electrophoresis, and mass spectrometry. Effects of mouse background on Microbial Composition were assessed by reciprocal colonization of germ-free mice from both background strains, followed by Compositional analysis of resultant gut bacterial communities using terminal restriction fragment length polymorphism analysis and 16 S qPCR. Our results revealed that 129/SvEv mice possessed fewer Paneth cells and a divergent AMP profile relative to C57BL/
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mouse paneth cell antiMicrobial function is independent of nod2
Gut, 2014Co-Authors: Michael J Shanahan, Emily Grossniklaus, Richard J Von Furstenberg, Susan J Henning, Balfour R Sartor, Ian M Carroll, Andrew M White, Roshonda Barner, Anthony A Fodor, Ajay S GulatiAbstract:Objective Although polymorphisms of the NOD2 gene predispose to the development of ileal Crohn9s disease, the precise mechanisms of this increased susceptibility remain unclear. Previous work has shown that transcript expression of the Paneth cell (PC) antiMicrobial peptides (AMPs) α-defensin 4 and α-defensin-related sequence 10 are selectively decreased in Nod2 −/− mice. However, the specific mouse background used in this previous study is unclear. In light of recent evidence suggesting that mouse strain strongly influences PC antiMicrobial activity, we sought to characterise PC AMP function in commercially available Nod2 −/− mice on a C57BL/6 (B6) background. Specifically, we hypothesised that Nod2 −/− B6 mice would display reduced AMP expression and activity. Design Wild-type (WT) and Nod2 −/− B6 ileal AMP expression was assessed via real-time PCR, acid urea polyacrylamide gel electrophoresis and mass spectrometry. PCs were enumerated using flow cytometry. Functionally, α-defensin bactericidal activity was evaluated using a gel-overlay antiMicrobial assay. Faecal Microbial Composition was determined using 454-sequencing of the bacterial 16S gene in cohoused WT and Nod2 −/− littermates. Results WT and Nod2 −/− B6 mice displayed similar PC AMP expression patterns, equivalent α-defensin profiles, and identical antiMicrobial activity against commensal and pathogenic bacterial strains. Furthermore, minimal differences in gut Microbial Composition were detected between the two cohoused, littermate mouse groups. Conclusions Our data reveal that Nod2 does not directly regulate PC antiMicrobial activity in B6 mice. Moreover, we demonstrate that previously reported Nod2-dependent influences on gut Microbial Composition may be overcome by environmental factors, such as cohousing with WT littermates.
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inflammatory bowel diseases phenotype c difficile and nod2 genotype are associated with shifts in human ileum associated Microbial Composition
PLOS ONE, 2012Co-Authors: Christina M Hamm, Ajay S Gulati, Balfour R Sartor, Hongyan Chen, Tianyi Zhang, James F Rohlf, Wei Zhu, Charles E Robertson, Norman R Pace, Edgar C BoedekerAbstract:We tested the hypothesis that Crohn’s disease (CD)-related genetic polymorphisms involved in host innate immunity are associated with shifts in human ileum–associated Microbial Composition in a cross-sectional analysis of human ileal samples. Sanger sequencing of the bacterial 16S ribosomal RNA (rRNA) gene and 454 sequencing of 16S rRNA gene hypervariable regions (V1–V3 and V3–V5), were conducted on macroscopically disease-unaffected ileal biopsies collected from 52 ileal CD, 58 ulcerative colitis and 60 control patients without inflammatory bowel diseases (IBD) undergoing initial surgical resection. These subjects also were genotyped for the three major NOD2 risk alleles (Leu1007fs, R708W, G908R) and the ATG16L1 risk allele (T300A). The samples were linked to clinical metadata, including body mass index, smoking status and Clostridia difficile infection. The sequences were classified into seven phyla/subphyla categories using the Naive Bayesian Classifier of the Ribosome Database Project. Centered log ratio transformation of six predominant categories was included as the dependent variable in the permutation based MANCOVA for the overall Composition with stepwise variable selection. Polymerase chain reaction (PCR) assays were conducted to measure the relative frequencies of the Clostridium coccoides – Eubacterium rectales group and the Faecalibacterium prausnitzii spp. Empiric logit transformations of the relative frequencies of these two Microbial groups were included in permutation-based ANCOVA. Regardless of sequencing method, IBD phenotype, Clostridia difficile and NOD2 genotype were selected as associated (FDR ≤0.05) with shifts in overall Microbial Composition. IBD phenotype and NOD2 genotype were also selected as associated with shifts in the relative frequency of the C. coccoides – E. rectales group. IBD phenotype, smoking and IBD medications were selected as associated with shifts in the relative frequency of F. prausnitzii spp. These results indicate that the effects of genetic and environmental factors on IBD are mediated at least in part by the enteric microbiota.
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mouse background strain profoundly influences paneth cell function and intestinal Microbial Composition
PLOS ONE, 2012Co-Authors: Ajay S Gulati, Michael J Shanahan, Janelle C Arthur, Emily Grossniklaus, Richard J Von Furstenberg, Lieselotte S M Kreuk, Susan J Henning, Christian Jobin, Balfour R SartorAbstract:Background Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota.
Monica Gatti - One of the best experts on this subject based on the ideXlab platform.
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natural whey starter for parmigiano reggiano culture independent approach
Journal of Applied Microbiology, 2010Co-Authors: Benedetta Bottari, Erasmo Neviani, Marcela Santarelli, Monica GattiAbstract:Aims: The aim of this work was to obtain a deeper insight into the knowledge of Microbial Composition of Parmigiano Reggiano natural whey starters through different culture-independent methods. Methods and Results: Eighteen different Parmigiano Reggiano natural whey starters sampled from three different provinces of this cheese production area and the nonacidified wheys from which they arose have been studied by length heterogeneity polymerase chain reaction (LH-PCR) and fluorescent in situ hybridization (FISH). A high Microbial Composition variability between different samples has been observed. Conclusions: Revealing different images of the same community, LH-PCR and FISH have given a more accurate view of the not well-known Parmigiano Reggiano whey starter ecosystem. Significance and Impact of the Study: New lights have been shed on Parmigiano Reggiano natural whey starters Microbial Composition, highlighting how culture-independent approach could be used and improved to study this and other food ecosystems.
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grana padano cheese whey starters Microbial Composition and strain distribution
International Journal of Food Microbiology, 2008Co-Authors: Lia Rossetti, Maria Emanuela Fornasari, Monica Gatti, Erasmo Neviani, Giorgio GiraffaAbstract:Abstract The aim of this work was to evaluate the species Composition and the genotypic strain heterogeneity of dominant lactic acid bacteria (LAB) isolated from whey starter cultures used to manufacture Grana Padano cheese. Twenty-four Grana Padano cheese whey starters collected from dairies located over a wide geographic production area in the north of Italy were analyzed. Total thermophilic LAB streptococci and lactobacilli were quantified by agar plate counting. Population structure of the dominant and metabolically active LAB species present in the starters was profiled by reverse transcriptase, length heterogeneity-PCR (RT–LH–PCR), a culture-independent technique successfully applied to study whey starter ecosystems. The dominant bacterial species were Lactobacillus helveticus, Lactobacillus delbrueckii subsp. lactis, Streptococcus thermophilus, and Lactobacillus fermentum. Diversity in the species Composition allowed the whey cultures to be grouped into four main typologies, the one containing L. helveticus, L. delbrueckii subsp. lactis, and S. thermophilus being the most frequent one (45% of the cultures analyzed), followed by that containing only the two lactobacilli (40%). Only a minor fraction of the cultures contained L. helveticus alone (4%) or all the four LAB species (11%). Five hundred and twelve strains were isolated from the 24 cultures and identified by M13-PCR fingerprinting coupled with 16S rRNA gene sequencing. Most of the strains were L. helveticus (190 strains; 37% of the total), L delbrueckii subsp. lactis (90 strains; 18%) and S. thermophilus (215 strains; 42%). This result was in good agreement with the qualitative whey starter Composition observed by RT–LH–PCR. M13-PCR fingerprinting indicated a markedly low infra-species diversity, i.e. the same biotypes were often found in more than one culture. The distribution of the biotypes into the different cultures was mainly dairy plant-specific rather than correlated with the different production areas.
Emily Grossniklaus - One of the best experts on this subject based on the ideXlab platform.
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Mouse Background Strain Profoundly Influences Paneth Cell Function and Intestinal Microbial Composition
2016Co-Authors: Ajay S Gulati, Janelle C Arthur, Emily Grossniklaus, Lieselotte S M Kreuk, Susan J Henning, Michael T. Shanahan, Richard J. Von, Balfour R SartorAbstract:Background: Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota. Methodology and Principal Findings: Paneth cell numbers were determined by flow cytometry. AntiMicrobial peptide (AMP) expression was evaluated using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), acid urea-polyacrylamide gel electrophoresis, and mass spectrometry. Effects of mouse background on Microbial Composition were assessed by reciprocal colonization of germ-free mice from both background strains, followed by Compositional analysis of resultant gut bacterial communities using terminal restriction fragment length polymorphism analysis and 16 S qPCR. Our results revealed that 129/SvEv mice possessed fewer Paneth cells and a divergent AMP profile relative to C57BL/
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mouse paneth cell antiMicrobial function is independent of nod2
Gut, 2014Co-Authors: Michael J Shanahan, Emily Grossniklaus, Richard J Von Furstenberg, Susan J Henning, Balfour R Sartor, Ian M Carroll, Andrew M White, Roshonda Barner, Anthony A Fodor, Ajay S GulatiAbstract:Objective Although polymorphisms of the NOD2 gene predispose to the development of ileal Crohn9s disease, the precise mechanisms of this increased susceptibility remain unclear. Previous work has shown that transcript expression of the Paneth cell (PC) antiMicrobial peptides (AMPs) α-defensin 4 and α-defensin-related sequence 10 are selectively decreased in Nod2 −/− mice. However, the specific mouse background used in this previous study is unclear. In light of recent evidence suggesting that mouse strain strongly influences PC antiMicrobial activity, we sought to characterise PC AMP function in commercially available Nod2 −/− mice on a C57BL/6 (B6) background. Specifically, we hypothesised that Nod2 −/− B6 mice would display reduced AMP expression and activity. Design Wild-type (WT) and Nod2 −/− B6 ileal AMP expression was assessed via real-time PCR, acid urea polyacrylamide gel electrophoresis and mass spectrometry. PCs were enumerated using flow cytometry. Functionally, α-defensin bactericidal activity was evaluated using a gel-overlay antiMicrobial assay. Faecal Microbial Composition was determined using 454-sequencing of the bacterial 16S gene in cohoused WT and Nod2 −/− littermates. Results WT and Nod2 −/− B6 mice displayed similar PC AMP expression patterns, equivalent α-defensin profiles, and identical antiMicrobial activity against commensal and pathogenic bacterial strains. Furthermore, minimal differences in gut Microbial Composition were detected between the two cohoused, littermate mouse groups. Conclusions Our data reveal that Nod2 does not directly regulate PC antiMicrobial activity in B6 mice. Moreover, we demonstrate that previously reported Nod2-dependent influences on gut Microbial Composition may be overcome by environmental factors, such as cohousing with WT littermates.
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mouse background strain profoundly influences paneth cell function and intestinal Microbial Composition
PLOS ONE, 2012Co-Authors: Ajay S Gulati, Michael J Shanahan, Janelle C Arthur, Emily Grossniklaus, Richard J Von Furstenberg, Lieselotte S M Kreuk, Susan J Henning, Christian Jobin, Balfour R SartorAbstract:Background Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota.
Susan J Henning - One of the best experts on this subject based on the ideXlab platform.
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Mouse Background Strain Profoundly Influences Paneth Cell Function and Intestinal Microbial Composition
2016Co-Authors: Ajay S Gulati, Janelle C Arthur, Emily Grossniklaus, Lieselotte S M Kreuk, Susan J Henning, Michael T. Shanahan, Richard J. Von, Balfour R SartorAbstract:Background: Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota. Methodology and Principal Findings: Paneth cell numbers were determined by flow cytometry. AntiMicrobial peptide (AMP) expression was evaluated using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), acid urea-polyacrylamide gel electrophoresis, and mass spectrometry. Effects of mouse background on Microbial Composition were assessed by reciprocal colonization of germ-free mice from both background strains, followed by Compositional analysis of resultant gut bacterial communities using terminal restriction fragment length polymorphism analysis and 16 S qPCR. Our results revealed that 129/SvEv mice possessed fewer Paneth cells and a divergent AMP profile relative to C57BL/
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mouse paneth cell antiMicrobial function is independent of nod2
Gut, 2014Co-Authors: Michael J Shanahan, Emily Grossniklaus, Richard J Von Furstenberg, Susan J Henning, Balfour R Sartor, Ian M Carroll, Andrew M White, Roshonda Barner, Anthony A Fodor, Ajay S GulatiAbstract:Objective Although polymorphisms of the NOD2 gene predispose to the development of ileal Crohn9s disease, the precise mechanisms of this increased susceptibility remain unclear. Previous work has shown that transcript expression of the Paneth cell (PC) antiMicrobial peptides (AMPs) α-defensin 4 and α-defensin-related sequence 10 are selectively decreased in Nod2 −/− mice. However, the specific mouse background used in this previous study is unclear. In light of recent evidence suggesting that mouse strain strongly influences PC antiMicrobial activity, we sought to characterise PC AMP function in commercially available Nod2 −/− mice on a C57BL/6 (B6) background. Specifically, we hypothesised that Nod2 −/− B6 mice would display reduced AMP expression and activity. Design Wild-type (WT) and Nod2 −/− B6 ileal AMP expression was assessed via real-time PCR, acid urea polyacrylamide gel electrophoresis and mass spectrometry. PCs were enumerated using flow cytometry. Functionally, α-defensin bactericidal activity was evaluated using a gel-overlay antiMicrobial assay. Faecal Microbial Composition was determined using 454-sequencing of the bacterial 16S gene in cohoused WT and Nod2 −/− littermates. Results WT and Nod2 −/− B6 mice displayed similar PC AMP expression patterns, equivalent α-defensin profiles, and identical antiMicrobial activity against commensal and pathogenic bacterial strains. Furthermore, minimal differences in gut Microbial Composition were detected between the two cohoused, littermate mouse groups. Conclusions Our data reveal that Nod2 does not directly regulate PC antiMicrobial activity in B6 mice. Moreover, we demonstrate that previously reported Nod2-dependent influences on gut Microbial Composition may be overcome by environmental factors, such as cohousing with WT littermates.
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mouse background strain profoundly influences paneth cell function and intestinal Microbial Composition
PLOS ONE, 2012Co-Authors: Ajay S Gulati, Michael J Shanahan, Janelle C Arthur, Emily Grossniklaus, Richard J Von Furstenberg, Lieselotte S M Kreuk, Susan J Henning, Christian Jobin, Balfour R SartorAbstract:Background Increasing evidence supports the central role of Paneth cells in maintaining intestinal host-Microbial homeostasis. However, the direct impact of host genotype on Paneth cell function remains unclear. Here, we characterize key differences in Paneth cell function and intestinal Microbial Composition in two widely utilized, genetically distinct mouse strains (C57BL/6 and 129/SvEv). In doing so, we demonstrate critical influences of host genotype on Paneth cell activity and the enteric microbiota.