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Freddy Haesebrouck - One of the best experts on this subject based on the ideXlab platform.
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The Other Helicobacters.
Helicobacter, 2020Co-Authors: Bram Flahou, Freddy Haesebrouck, Emiko Rimbara, Shigetarou Mori, Keigo ShibayamaAbstract:In the past year, a substantial number of (putative) novel Helicobacter species have been described, including Helicobacter himalayensis colonizing the Himalayan marmot and Helicobacter apodemus, colonizing the Korean striped field mouse. In addition, a putative novel gastric Helicobacter species was identified in wild gorillas and chimpanzees, for which the name "Candidatus H. homininae" was proposed. A high incidence of gastric non-H. pylori Helicobacter infection was described in China and multiple case reports have described the involvement of enterohepatic Helicobacter species, especially Helicobacter cinaedi, in a wide range of diseases. Several studies in rodent models further elucidated the mechanisms underlying the development of gastric mucosa-associated lymphoid tissue lymphoma during infection with gastric non-H. pylori Helicobacters. The effects of infection with gastric Helicobacters on the development of neuroinflammation were investigated and several enterohepatic Helicobacter species were shown to affect the composition of the gut microbiota, to influence vaccine efficiency as well as the progression of cancer in distant sites of the body.
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The other Helicobacters.
Helicobacter, 2020Co-Authors: Annemieke Smet, Bram Flahou, Freddy Haesebrouck, Richard Ducatelle, Indrani Mukhopadhya, Frank Pasmans, Georgina L HoldAbstract:The last year has seen an interesting and important collection of evidence presented in the field of the "other" than Helicobacter pylori Helicobacters. Associations with adult ulcerative colitis and biliary/hepatic disease have been described. New insights into the immune response and subsequent pathogenesis associated with infection have also been published. Genomic advances include description of new and unique species and the complete genome description for both Helicobacter felis and Helicobacter suis. Molecular studies have also elucidated the mechanism of action of some functional components of these organisms.
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Gastric and enterohepatic Helicobacters other than Helicobacter pylori.
Helicobacter, 2020Co-Authors: Armelle Ménard, Freddy Haesebrouck, Christelle Péré-védrenne, Bram FlahouAbstract:During the past year, research on non-Helicobacter pylori species has intensified. H. valdiviensis was isolated from wild birds, and putative novel species have been isolated from Bengal tigers and Australian marsupials. Various genomes have been sequenced: H. bilis, H. canis, H. macacae, H. fennelliae, H. cetorum, and H. suis. Several studies highlighted the virulence of non-H. pylori species including H. cinaedi in humans and hyperlipidemic mice or H. macacae in geriatric rhesus monkeys with intestinal adenocarcinoma. Not surprisingly, increased attention has been paid to the position of Helicobacter species in the microbiota of children and animal species (mice, chickens, penguins, and migrating birds). A large number of experimental studies have been performed in animal models of Helicobacter induced typhlocolitis, showing that the gastrointestinal microbial community is involved in modulation of host pathways leading to chronic inflammation. Animal models of H. suis, H. heilmannii, and H. felis infection have been used to study the development of severe inflammation-related pathologies, including gastric MALT lymphoma and adenocarcinoma.
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Extragastric manifestations of Helicobacter pylori infection: other Helicobacters.
Helicobacter, 2020Co-Authors: Hilde Moyaert, Freddy Haesebrouck, Richard Ducatelle, Francesco Franceschi, Davide Roccarina, Antonio GasbarriniAbstract:The finding that Helicobacter pylori is the main cause of gastritis and peptic ulcer disease has opened a new era in the gastrointestinal world. Today there is evidence that H. pylori may also play a role in different nongastric diseases, opening the new "extragastric manifestations of H. pylori infection" field. Concerning this, several studies have been published in the last year. The most convincing data arise from those investigating idiopathic thrombocytopenic purpura and sideropenic anemia, while there is also an increasing evidence for a possible association with atherosclerotic disease. Furthermore, the discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. In particular, several species have been studied for a potential role in different liver and intestinal diseases with interesting findings.
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Non-Helicobacter pylori Helicobacter Infections in Humans and Animals
Helicobacter pylori Research, 2016Co-Authors: Bram Flahou, Freddy Haesebrouck, Annemieke SmetAbstract:Since the first description of the human pathogen Helicobacter pylori in the early 1980s, the number of known species in the genus Helicobacter has increased largely. Currently, 45 different Helicobacter species have been identified. Bacteria belonging to this genus can roughly be divided into two major groups, gastric and enterohepatic species. Gastric Helicobacters express urease at a high level which helps them to survive in the acidic environment of the stomach, whereas most enterohepatic Helicobacters do not. The best-known gastric Helicobacter species is H. pylori. This chapter, however, deals with non-H. pylori Helicobacters (NHPH). Most NHPH are animal-associated bacteria, but some of them are of zoonotic significance. First, gastric infections with these bacteria in humans are considered. Thereafter, an overview of natural and experimental gastric infections in animal hosts is given, with emphasis on the gastric Helicobacters that are mainly associated with dogs, cats, and pigs. Finally, enterohepatic Helicobacter species are briefly discussed.
Richard Ducatelle - One of the best experts on this subject based on the ideXlab platform.
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Extragastric manifestations of Helicobacter pylori infection: other Helicobacters.
Helicobacter, 2020Co-Authors: Hilde Moyaert, Freddy Haesebrouck, Richard Ducatelle, Francesco Franceschi, Davide Roccarina, Antonio GasbarriniAbstract:The finding that Helicobacter pylori is the main cause of gastritis and peptic ulcer disease has opened a new era in the gastrointestinal world. Today there is evidence that H. pylori may also play a role in different nongastric diseases, opening the new "extragastric manifestations of H. pylori infection" field. Concerning this, several studies have been published in the last year. The most convincing data arise from those investigating idiopathic thrombocytopenic purpura and sideropenic anemia, while there is also an increasing evidence for a possible association with atherosclerotic disease. Furthermore, the discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. In particular, several species have been studied for a potential role in different liver and intestinal diseases with interesting findings.
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The other Helicobacters.
Helicobacter, 2020Co-Authors: Annemieke Smet, Bram Flahou, Freddy Haesebrouck, Richard Ducatelle, Indrani Mukhopadhya, Frank Pasmans, Georgina L HoldAbstract:The last year has seen an interesting and important collection of evidence presented in the field of the "other" than Helicobacter pylori Helicobacters. Associations with adult ulcerative colitis and biliary/hepatic disease have been described. New insights into the immune response and subsequent pathogenesis associated with infection have also been published. Genomic advances include description of new and unique species and the complete genome description for both Helicobacter felis and Helicobacter suis. Molecular studies have also elucidated the mechanism of action of some functional components of these organisms.
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effects of Helicobacter suis γ glutamyl transpeptidase on lymphocytes modulation by glutamine and glutathione supplementation and outer membrane vesicles as a putative delivery route of the enzyme
PLOS ONE, 2013Co-Authors: Guangzhi Zhang, Freddy Haesebrouck, Annemieke Smet, Richard Ducatelle, Frank Pasmans, Katharina Dherde, Liping Huang, Bram FlahouAbstract:Helicobacter (H.) suis colonizes the stomach of the majority of pigs as well as a minority of humans worldwide. Infection causes chronic inflammation in the stomach of the host, however without an effective clearance of the bacteria. Currently, no information is available about possible mechanisms H. suis utilizes to interfere with the host immune response. This study describes the effect on various lymphocytes of the γ-glutamyl transpeptidase (GGT) from H. suis. Compared to whole cell lysate from wild-type H. suis, lysate from a H. suis ggt mutant strain showed a decrease of the capacity to inhibit Jurkat T cell proliferation. Incubation of Jurkat T cells with recombinantly expressed H. suis GGT resulted in an impaired proliferation, and cell death was shown to be involved. A similar but more pronounced inhibitory effect was also seen on primary murine CD4+ T cells, CD8+ T cells, and CD19+ B cells. Supplementation with known GGT substrates was able to modulate the observed effects. Glutamine restored normal proliferation of the cells, whereas supplementation with reduced glutathione strengthened the H. suis GGT-mediated inhibition of proliferation. H. suis GGT treatment abolished secretion of IL-4 and IL-17 by CD4+ T cells, without affecting secretion of IFN-γ. Finally, H. suis outer membrane vesicles (OMV) were identified as a possible delivery route of H. suis GGT to lymphocytes residing in the deeper mucosal layers. Thus far, this study is the first to report that the effects on lymphocytes of this enzyme, not only important for H. suis metabolism but also for that of other Helicobacter species, depend on the degradation of two specific substrates: glutamine and reduced glutatione. This will provide new insights into the pathogenic mechanisms of H. suis infection in particular and infection with gastric Helicobacters in general.
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The Other Helicobacters: Other Helicobacters
Helicobacter, 2011Co-Authors: Annemieke Smet, Bram Flahou, Freddy Haesebrouck, Richard Ducatelle, Indrani Mukhopadhya, Frank Pasmans, Georgina L HoldAbstract:The last year has seen an interesting and important collection of evidence presented in the field of the "other" than Helicobacter pylori Helicobacters. Associations with adult ulcerative colitis and biliary/hepatic disease have been described. New insights into the immune response and subsequent pathogenesis associated with infection have also been published. Genomic advances include description of new and unique species and the complete genome description for both Helicobacter felis and Helicobacter suis. Molecular studies have also elucidated the mechanism of action of some functional components of these organisms
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Non-Helicobacter pylori Helicobacters detected in the stomach of humans comprise several naturally occurring Helicobacter species in animals.
Fems Immunology and Medical Microbiology, 2009Co-Authors: Margo Baele, Bram Flahou, Richard Ducatelle, Frank Pasmans, Koen Chiers, Freddy HaesebrouckAbstract:Besides the well-known gastric pathogen Helicobacter pylori, other Helicobacter species with a spiral morphology have been detected in a minority of human patients who have undergone gastroscopy. The very fastidious nature of these non-Helicobacter pylori Helicobacters (NHPH) makes their in vitro isolation difficult. These organisms have been designated 'Helicobacter heilmannii'. However, sequencing of several genes detected in NHPH-infected tissues has shown that the 'H. heilmannii' group comprises at least five different Helicobacter species, all of them known to colonize the stomach of animals. Recent investigations have indicated that Helicobacter suis is the most prevalent NHPH species in human. This species has only recently been isolated in vitro from porcine stomach mucosa. Other NHPH that colonize the human stomach are Helicobacter felis, Helicobacter bizzozeronii, Helicobacter salomonis and 'Candidatus Helicobacter heilmannii'. In numerous case reports of human gastric NHPH infections, no substantial information is available about the species status of the infecting strain, making it difficult to link the species with certain pathologies. This review aims to clarify the complex nomenclature of NHPH species associated with human gastric disease and their possible animal origin. It is proposed to use the term 'gastric NHPH' to designate gastric spirals that are morphologically different from H. pylori when no identification is available at the species level. Species designations should be reserved for those situations in which the species is defined.
Bram Flahou - One of the best experts on this subject based on the ideXlab platform.
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The Other Helicobacters.
Helicobacter, 2020Co-Authors: Bram Flahou, Freddy Haesebrouck, Emiko Rimbara, Shigetarou Mori, Keigo ShibayamaAbstract:In the past year, a substantial number of (putative) novel Helicobacter species have been described, including Helicobacter himalayensis colonizing the Himalayan marmot and Helicobacter apodemus, colonizing the Korean striped field mouse. In addition, a putative novel gastric Helicobacter species was identified in wild gorillas and chimpanzees, for which the name "Candidatus H. homininae" was proposed. A high incidence of gastric non-H. pylori Helicobacter infection was described in China and multiple case reports have described the involvement of enterohepatic Helicobacter species, especially Helicobacter cinaedi, in a wide range of diseases. Several studies in rodent models further elucidated the mechanisms underlying the development of gastric mucosa-associated lymphoid tissue lymphoma during infection with gastric non-H. pylori Helicobacters. The effects of infection with gastric Helicobacters on the development of neuroinflammation were investigated and several enterohepatic Helicobacter species were shown to affect the composition of the gut microbiota, to influence vaccine efficiency as well as the progression of cancer in distant sites of the body.
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The other Helicobacters.
Helicobacter, 2020Co-Authors: Annemieke Smet, Bram Flahou, Freddy Haesebrouck, Richard Ducatelle, Indrani Mukhopadhya, Frank Pasmans, Georgina L HoldAbstract:The last year has seen an interesting and important collection of evidence presented in the field of the "other" than Helicobacter pylori Helicobacters. Associations with adult ulcerative colitis and biliary/hepatic disease have been described. New insights into the immune response and subsequent pathogenesis associated with infection have also been published. Genomic advances include description of new and unique species and the complete genome description for both Helicobacter felis and Helicobacter suis. Molecular studies have also elucidated the mechanism of action of some functional components of these organisms.
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Other Helicobacters, gastric and gut microbiota.
Helicobacter, 2020Co-Authors: Christelle Péré-védrenne, Bram Flahou, Armelle Ménard, Mun Fai Loke, Jamuna VadiveluAbstract:The current article is a review of the most important and relevant literature published in 2016 and early 2017 on non-Helicobacter pylori Helicobacter infections in humans and animals, as well as interactions between H. pylori and the microbiota of the stomach and other organs. Some putative new Helicobacter species were identified in sea otters, wild boars, dogs, and mice. Many cases of Helicobacter fennelliae and Helicobacter cinaedi infection have been reported in humans, mostly in immunocompromised patients. Mouse models have been used frequently as a model to investigate human Helicobacter infection, although some studies have investigated the pathogenesis of Helicobacters in their natural host, as was the case for Helicobacter suis infection in pigs. Our understanding of both the gastric and gut microbiome has made progress and, in addition, interactions between H. pylori and the microbiome were demonstrated to go beyond the stomach. Some new approaches of preventing Helicobacter infection or its related pathologies were investigated and, in this respect, the probiotic properties of Saccharomyces, Lactobacillus and Bifidobacterium spp. were confirmed.
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Gastric and enterohepatic Helicobacters other than Helicobacter pylori.
Helicobacter, 2020Co-Authors: Armelle Ménard, Freddy Haesebrouck, Christelle Péré-védrenne, Bram FlahouAbstract:During the past year, research on non-Helicobacter pylori species has intensified. H. valdiviensis was isolated from wild birds, and putative novel species have been isolated from Bengal tigers and Australian marsupials. Various genomes have been sequenced: H. bilis, H. canis, H. macacae, H. fennelliae, H. cetorum, and H. suis. Several studies highlighted the virulence of non-H. pylori species including H. cinaedi in humans and hyperlipidemic mice or H. macacae in geriatric rhesus monkeys with intestinal adenocarcinoma. Not surprisingly, increased attention has been paid to the position of Helicobacter species in the microbiota of children and animal species (mice, chickens, penguins, and migrating birds). A large number of experimental studies have been performed in animal models of Helicobacter induced typhlocolitis, showing that the gastrointestinal microbial community is involved in modulation of host pathways leading to chronic inflammation. Animal models of H. suis, H. heilmannii, and H. felis infection have been used to study the development of severe inflammation-related pathologies, including gastric MALT lymphoma and adenocarcinoma.
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Non-Helicobacter pylori Helicobacter Infections in Humans and Animals
Helicobacter pylori Research, 2016Co-Authors: Bram Flahou, Freddy Haesebrouck, Annemieke SmetAbstract:Since the first description of the human pathogen Helicobacter pylori in the early 1980s, the number of known species in the genus Helicobacter has increased largely. Currently, 45 different Helicobacter species have been identified. Bacteria belonging to this genus can roughly be divided into two major groups, gastric and enterohepatic species. Gastric Helicobacters express urease at a high level which helps them to survive in the acidic environment of the stomach, whereas most enterohepatic Helicobacters do not. The best-known gastric Helicobacter species is H. pylori. This chapter, however, deals with non-H. pylori Helicobacters (NHPH). Most NHPH are animal-associated bacteria, but some of them are of zoonotic significance. First, gastric infections with these bacteria in humans are considered. Thereafter, an overview of natural and experimental gastric infections in animal hosts is given, with emphasis on the gastric Helicobacters that are mainly associated with dogs, cats, and pigs. Finally, enterohepatic Helicobacter species are briefly discussed.
Hien Q. Huynh - One of the best experts on this subject based on the ideXlab platform.
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Helicobacter pylori Induces Expression and Secretion of Oncostatin M in Macrophages In Vitro
Digestive Diseases and Sciences, 2011Co-Authors: Zaher Zeaiter, Hugo Diaz, Markus Stein, Hien Q. HuynhAbstract:Background Helicobacter pylori is pathogenic bacterium that is associated with several gastric diseases in humans. Disease is characterized by severe inflammatory responses is the stomach that are induced by various chemokines and cytokines. Previous reports indicated that some of these responses are mediated through Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling. Methods We performed JAK/STAT specific microarrays to identify new components of this signaling pathway, which are affected by Helicobacter pylori infection of THP-1 cells. Results We found that expression and secretion of oncostatin M and of its receptor were strongly up-regulated by Helicobacter pylori . OSM secretion was independent of CagA, VacA or Type IV secretion system. Helicobacter pylori culture supernatant induced OSM secretion. Conclusion The induction of the pleiotropic cytokine oncostatin M suggests a possible role in Helicobacter pylori -mediated inflammation and diseases.
Antonio Gasbarrini - One of the best experts on this subject based on the ideXlab platform.
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Helicobacter pylori and extragastric diseases -- other Helicobacters.
Helicobacter, 2020Co-Authors: Antonio Gasbarrini, Emilia Carloni, Giovanni Gasbarrini, Armelle MénardAbstract:The role of Helicobacter pylori infection is explored in more and more extragastric diseases without definite proof in most of the studies, except possibly some hematologic diseases. In cardiovascular diseases, including stroke, the presence of CagA positive strains may be involved. The possible role of Helicobacters in hepatobiliary diseases goes beyond that of H. pylori to involve enterohepatic Helicobacters. New Helicobacter species are regularly described and molecular methods are developed to improve their detection. Helicobacter felis remains the major species to be used in animal models of Helicobacter infection.
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Helicobacter pylori and extragastric diseases--other Helicobacters.
Helicobacter, 2020Co-Authors: Antonio Gasbarrini, Emilia Carloni, Giovanni Gasbarrini, Stephanie A ChisholmAbstract:Reports on Helicobacter pylori and extragastric diseases have almost doubled this year compared with last year, bearing witness to the persistent scientific interest in this branch of Helicobacter-related pathology. Data belong increasingly to the area of vascular medicine, as well as hematology, dermatology, pediatrics and other fields. Unfortunately, these studies show overall controversial results, due to the impact of several confounding factors, and to the difficulty of recruiting homogeneous patient populations. Furthermore, many studies continue to be conducted on Helicobacter species other than H. pylori, focusing on animal models of gastroenterological illnesses which may retain strong similarities with human diseases. In this paper, taxonomy, detection and characterisation of Helicobacter spp. will be reviewed, together with the most important data issued this year on other Helicobacters and animal models.
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Extragastric manifestations of Helicobacter pylori infection -- other Helicobacters.
Helicobacter, 2020Co-Authors: Ulrich R. M. Bohr, Bruno Annibale, Francesco Franceschi, Davide Roccarina, Antonio GasbarriniAbstract:Today there is evidence that Helicobacter pylori has a critical role in different extragastric diseases. The discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. Enterohepatic Helicobacter species have been hypothesized to play a role in different disorders, including hepatocellular carcinoma, gallstones formation and cholangiocellular carcinoma, as well as enteric diseases and inflammatory bowel diseases. Concerning the extragastric manifestations of H. pylori infection, idiopathic thrombocytopenic purpura, and sideropenic anemia represent, based on the current data, the diseases in which the pathogenic link appears to be strongest. There is also an increasing evidence for a possible association of H. pylori with cardiovascular disease.
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Extragastric manifestations of Helicobacter pylori infection: other Helicobacters.
Helicobacter, 2020Co-Authors: Hilde Moyaert, Freddy Haesebrouck, Richard Ducatelle, Francesco Franceschi, Davide Roccarina, Antonio GasbarriniAbstract:The finding that Helicobacter pylori is the main cause of gastritis and peptic ulcer disease has opened a new era in the gastrointestinal world. Today there is evidence that H. pylori may also play a role in different nongastric diseases, opening the new "extragastric manifestations of H. pylori infection" field. Concerning this, several studies have been published in the last year. The most convincing data arise from those investigating idiopathic thrombocytopenic purpura and sideropenic anemia, while there is also an increasing evidence for a possible association with atherosclerotic disease. Furthermore, the discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. In particular, several species have been studied for a potential role in different liver and intestinal diseases with interesting findings.
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Extragastric manifestations of Helicobacter pylori infection--other Helicobacter species.
Helicobacter, 2020Co-Authors: Jay V Solnick, Davide Roccarina, Francesco Franceschi, Antonio GasbarriniAbstract:Recent studies have indicated a strong link between Helicobacter pylori and idiopathic thrombocytopenic purpura and iron deficiency anemia. Interesting results have also been obtained for ischemic heart disease, though most putative associations between H. pylori infection and extragastric disease remain speculative. With regard to other Helicobacter species, Helicobacter felis has been shown to play a role in gastric carcinogenesis in mouse models. An increased susceptibility to cholesterol gallstone formation has been described in animals fed a lithogenic diet and infected with Helicobacter bilis, or co-infected with Helicobacter hepaticus and Helicobacter rodentium. Finally, enterohepatic Helicobacter species have also been exploited to better understand inflammatory bowel disease.
