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Al-Fakhrany OM, Elekhnawy E. Helicobacter pylori in the post-antibiotics era: from virulence factors to new drug targets and therapeutic agents. Arch Microbiol 2023; 205:301. [PMID: 37550555 PMCID: PMC10406680 DOI: 10.1007/s00203-023-03639-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 07/16/2023] [Accepted: 07/20/2023] [Indexed: 08/09/2023]
Abstract
Helicobacter pylori is considered one of the most prevalent human pathogenic microbes globally. It is the main cause of a number of gastrointestinal ailments, including peptic and duodenal ulcers, and gastric tumors with high mortality rates. Thus, eradication of H. pylori is necessary to prevent gastric cancer. Still, the rise in antibiotic resistance is the most important challenge for eradication strategies. Better consideration of H. pylori virulence factors, pathogenesis, and resistance is required for better eradication rates and, thus, prevention of gastrointestinal malignancy. This article is aimed to show the role of virulence factors of H. pylori. Some are involved in its survival in the harsh environment of the human gastric lumen, and others are related to pathogenesis and the infection process. Furthermore, this work has highlighted the recent advancement in H. pylori treatment, as well as antibiotic resistance as a main challenge in H. pylori eradication. Also, we tried to provide an updated summary of the evolving H. pylori control strategies and the potential alternative drugs to fight this lethal resistant pathogen. Recent studies have focused on evaluating the efficacy of alternative regimens (such as sequential, hybrid, concomitant treatment, vonoprazan (VPZ)-based triple therapy, high-dose PPI-amoxicillin dual therapy, probiotics augmented triple therapy, or in combination with BQT) in the effective eradication of H. pylori. Thus, innovating new anti-H. pylori drugs and establishing H. pylori databanks are upcoming necessities in the near future.
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Affiliation(s)
- Omnia Momtaz Al-Fakhrany
- Pharmaceutical Microbiology Department, Faculty of Pharmacy, Tanta University, Tanta, 31527 Egypt
| | - Engy Elekhnawy
- Pharmaceutical Microbiology Department, Faculty of Pharmacy, Tanta University, Tanta, 31527 Egypt
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2
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Sijmons D, Guy AJ, Walduck AK, Ramsland PA. Helicobacter pylori and the Role of Lipopolysaccharide Variation in Innate Immune Evasion. Front Immunol 2022; 13:868225. [PMID: 35634347 PMCID: PMC9136243 DOI: 10.3389/fimmu.2022.868225] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/04/2022] [Indexed: 11/30/2022] Open
Abstract
Helicobacter pylori is an important human pathogen that infects half the human population and can lead to significant clinical outcomes such as acute and chronic gastritis, duodenal ulcer, and gastric adenocarcinoma. To establish infection, H. pylori employs several mechanisms to overcome the innate and adaptive immune systems. H. pylori can modulate interleukin (IL) secretion and innate immune cell function by the action of several virulence factors such as VacA, CagA and the type IV secretion system. Additionally, H. pylori can modulate local dendritic cells (DC) negatively impacting the function of these cells, reducing the secretion of immune signaling molecules, and influencing the differentiation of CD4+ T helper cells causing a bias to Th1 type cells. Furthermore, the lipopolysaccharide (LPS) of H. pylori displays a high degree of phase variation and contains human blood group carbohydrate determinants such as the Lewis system antigens, which are proposed to be involved in molecular mimicry of the host. Lastly, the H. pylori group of outer membrane proteins such as BabA play an important role in attachment and interaction with host Lewis and other carbohydrate antigens. This review examines the various mechanisms that H. pylori utilises to evade the innate immune system as well as discussing how the structure of the H. pylori LPS plays a role in immune evasion.
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Affiliation(s)
- Daniel Sijmons
- School of Science, RMIT University, Melbourne, VIC, Australia
| | - Andrew J. Guy
- School of Science, RMIT University, Melbourne, VIC, Australia
- ZiP Diagnostics, Collingwood, VIC, Australia
| | - Anna K. Walduck
- School of Science, RMIT University, Melbourne, VIC, Australia
| | - Paul A. Ramsland
- School of Science, RMIT University, Melbourne, VIC, Australia
- Department of Immunology, Monash University, Melbourne, VIC, Australia
- Department of Surgery, Austin Health, University of Melbourne, Heidelberg, VIC, Australia
- *Correspondence: Paul A. Ramsland,
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3
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Yuan LZ, Shi X, Tang D, Zheng SP, Xiao ZM, Wang F. Construction and preservation of a stable and highly expressed recombinant Helicobacter pylori vacuolating cytotoxin A with apoptotic activity. BMC Microbiol 2021; 21:229. [PMID: 34407768 PMCID: PMC8371779 DOI: 10.1186/s12866-021-02262-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 06/15/2021] [Indexed: 01/11/2023] Open
Abstract
Background H. pylori is closely related to the occurrence and development of various digestive gastritis, peptic ulcer and mucosa-associated lymphoid tissue (MALT) lymphoma. H. pylori is also a class I carcinogen of gastric cancer. VacA is the only exocrine toxin of H. pylori, which plays a very important role in the pathogenesis of H. pylori. The production of VacA in natural circumstances is complex with heavy workload and low yield. Therefore, it is very important to obtain recombinant VacA protein which is stable and biologically active. This study therefore aims to explore the expression, purification and stable storage of VacA toxin of H. pylori in E.coli, and to provide experimental basis for further exploration of the role of VacA in H. pylori -induced inflammation of cancer. Results A 2502-bp fragment and VacA gene were identified. An 89.7-kDa VacA34–854 recombinant protein was expressed and purified from the recombinant engineering bacteria and was preserved stably in 50 mM acetic acid buffer (pH 2.9). The amount of the recombinant protein was larger in the inclusion bodies than in the supernatant. In addition, after a 24-h culture with VacA recombinant protein, GES-1 cells demonstrated evidence of apoptosis including early nuclear immobilization and clustering under inverted microscope and TEM. It was found that VacA recombinant protein induced apoptosis by TUNEL assay. Conclusions A VacA recombinant protein that is stably and highly expressed and possesses pro-apoptotic activity is successfully constructed. The protein is stably preserved in 50 mM acetic acid buffer (pH 2.9). Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02262-7.
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Affiliation(s)
- Ling-Zhi Yuan
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Xiao Shi
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Dan Tang
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Shao-Peng Zheng
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Zhi-Ming Xiao
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Fen Wang
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China. .,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China.
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4
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Piscione M, Mazzone M, Di Marcantonio MC, Muraro R, Mincione G. Eradication of Helicobacter pylori and Gastric Cancer: A Controversial Relationship. Front Microbiol 2021; 12:630852. [PMID: 33613500 PMCID: PMC7889593 DOI: 10.3389/fmicb.2021.630852] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/14/2021] [Indexed: 12/15/2022] Open
Abstract
Worldwide, gastric cancer (GC) represents the fifth cancer for incidence, and the third as cause of death in developed countries. Indeed, it resulted in more than 780,000 deaths in 2018. Helicobacter pylori appears to be responsible for the majority of these cancers. On the basis of recent studies, and either alone or combined with additional etiological factors, H. pylori is considered a "type I carcinogen." Over recent decades, new insights have been obtained into the strategies that have been adopted by H. pylori to survive the acidic conditions of the gastric environment, and to result in persistent infection, and dysregulation of host functions. The multistep processes involved in the development of GC are initiated by transition of the mucosa into chronic non-atrophic gastritis, which is primarily triggered by infection with H. pylori. This gastritis then progresses into atrophic gastritis and intestinal metaplasia, and then to dysplasia, and following Correa's cascade, to adenocarcinoma. The use of antibiotics for eradication of H. pylori can reduce the incidence of precancerous lesions only in the early stages of gastric carcinogenesis. Here, we first survey the etiology and risk factors of GC, and then we analyze the mechanisms underlying tumorigenesis induced by H. pylori, focusing attention on virulence factor CagA, inflammation, oxidative stress, and ErbB2 receptor tyrosine kinase. Moreover, we investigate the relationships between H. pylori eradication therapy and other diseases, considering not only cardia (upper stomach) cancers and Barrett's esophagus, but also asthma and allergies, through discussion of the "hygiene hypothesis. " This hypothesis suggests that improved hygiene and antibiotic use in early life reduces microbial exposure, such that the immune response does not become primed, and individuals are not protected against atopic disorders, asthma, and autoimmune diseases. Finally, we overview recent advances to uncover the complex interplay between H. pylori and the gut microbiota during gastric carcinogenesis, as characterized by reduced bacterial diversity and increased microbial dysbiosis. Indeed, it is of particular importance to identify the bacterial taxa of the stomach that might predict the outcome of gastric disease through the stages of Correa's cascade, to improve prevention and therapy of gastric carcinoma.
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Affiliation(s)
| | | | | | | | - Gabriella Mincione
- Department of Innovative Technologies in Medicine and Dentistry, University “G. d’Annunzio” of Chieti–Pescara, Chieti, Italy
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5
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Baj J, Forma A, Sitarz M, Portincasa P, Garruti G, Krasowska D, Maciejewski R. Helicobacter pylori Virulence Factors-Mechanisms of Bacterial Pathogenicity in the Gastric Microenvironment. Cells 2020; 10:E27. [PMID: 33375694 PMCID: PMC7824444 DOI: 10.3390/cells10010027] [Citation(s) in RCA: 152] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/18/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
Gastric cancer constitutes one of the most prevalent malignancies in both sexes; it is currently the fourth major cause of cancer-related deaths worldwide. The pathogenesis of gastric cancer is associated with the interaction between genetic and environmental factors, among which infection by Helicobacter pylori (H. pylori) is of major importance. The invasion, survival, colonization, and stimulation of further inflammation within the gastric mucosa are possible due to several evasive mechanisms induced by the virulence factors that are expressed by the bacterium. The knowledge concerning the mechanisms of H. pylori pathogenicity is crucial to ameliorate eradication strategies preventing the possible induction of carcinogenesis. This review highlights the current state of knowledge and the most recent findings regarding H. pylori virulence factors and their relationship with gastric premalignant lesions and further carcinogenesis.
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Affiliation(s)
- Jacek Baj
- Department of Anatomy, Medical University of Lublin, 20-400 Lublin, Poland;
| | - Alicja Forma
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Monika Sitarz
- Department of Conservative Dentistry with Endodontics, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Piero Portincasa
- Clinica Medica “Augusto Murri”, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro”, 70124 Bari, Italy;
| | - Gabriella Garruti
- Section of Endocrinology, Department of Emergency and Organ Transplantations, University of Bari “Aldo Moro” Medical School, Piazza G. Cesare 11, 70124 Bari, Italy;
| | - Danuta Krasowska
- Department of Dermatology, Venerology and Paediatric Dermatology of Medical University of Lublin, 20-081 Lublin, Poland;
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6
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Pathways of Gastric Carcinogenesis, Helicobacter pylori Virulence and Interactions with Antioxidant Systems, Vitamin C and Phytochemicals. Int J Mol Sci 2020; 21:ijms21176451. [PMID: 32899442 PMCID: PMC7503565 DOI: 10.3390/ijms21176451] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 08/21/2020] [Accepted: 08/31/2020] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori is a class one carcinogen which causes chronic atrophic gastritis, gastric intestinal metaplasia, dysplasia and adenocarcinoma. The mechanisms by which H. pylori interacts with other risk and protective factors, particularly vitamin C in gastric carcinogenesis are complex. Gastric carcinogenesis includes metabolic, environmental, epigenetic, genomic, infective, inflammatory and oncogenic pathways. The molecular classification of gastric cancer subtypes has revolutionized the understanding of gastric carcinogenesis. This includes the tumour microenvironment, germline mutations, and the role of Helicobacter pylori bacteria, Epstein Barr virus and epigenetics in somatic mutations. There is evidence that ascorbic acid, phytochemicals and endogenous antioxidant systems can modify the risk of gastric cancer. Gastric juice ascorbate levels depend on dietary intake of ascorbic acid but can also be decreased by H. pylori infection, H. pylori CagA secretion, tobacco smoking, achlorhydria and chronic atrophic gastritis. Ascorbic acid may be protective against gastric cancer by its antioxidant effect in gastric cytoprotection, regenerating active vitamin E and glutathione, inhibiting endogenous N-nitrosation, reducing toxic effects of ingested nitrosodimethylamines and heterocyclic amines, and preventing H. pylori infection. The effectiveness of such cytoprotection is related to H. pylori strain virulence, particularly CagA expression. The role of vitamin C in epigenetic reprogramming in gastric cancer is still evolving. Other factors in conjunction with vitamin C also play a role in gastric carcinogenesis. Eradication of H. pylori may lead to recovery of vitamin C secretion by gastric epithelium and enable regression of premalignant gastric lesions, thereby interrupting the Correa cascade of gastric carcinogenesis.
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7
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Ansari S, Yamaoka Y. Helicobacter pylori Virulence Factors Exploiting Gastric Colonization and its Pathogenicity. Toxins (Basel) 2019; 11:E677. [PMID: 31752394 PMCID: PMC6891454 DOI: 10.3390/toxins11110677] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 11/15/2019] [Accepted: 11/16/2019] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori colonizes the gastric epithelial cells of at least half of the world's population, and it is the strongest risk factor for developing gastric complications like chronic gastritis, ulcer diseases, and gastric cancer. To successfully colonize and establish a persistent infection, the bacteria must overcome harsh gastric conditions. H. pylori has a well-developed mechanism by which it can survive in a very acidic niche. Despite bacterial factors, gastric environmental factors and host genetic constituents together play a co-operative role for gastric pathogenicity. The virulence factors include bacterial colonization factors BabA, SabA, OipA, and HopQ, and the virulence factors necessary for gastric pathogenicity include the effector proteins like CagA, VacA, HtrA, and the outer membrane vesicles. Bacterial factors are considered more important. Here, we summarize the recent information to better understand several bacterial virulence factors and their role in the pathogenic mechanism.
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Affiliation(s)
- Shamshul Ansari
- Department of Microbiology, Chitwan Medical College and Teaching Hospital, Bharatpur 44200, Chitwan, Nepal;
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka, Hasama-machi, Yufu, Oita 879-5593, Japan
- Global Oita Medical Advanced Research Center for Health, Idaigaoka, Hasama-machi, Yufu, Oita 879-5593, Japan
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, 2002 Holcombe Blvd., Houston, TX 77030, USA
- Borneo Medical and Health Research Centre, Universiti Malaysia Sabah, Kota Kinabaru, Sabah 88400, Malaysia
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8
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Bravo J, Díaz P, Corvalán AH, Quest AFG. A Novel Role for Helicobacter pylori Gamma-Glutamyltranspeptidase in Regulating Autophagy and Bacterial Internalization in Human Gastric Cells. Cancers (Basel) 2019; 11:cancers11060801. [PMID: 31185677 PMCID: PMC6627848 DOI: 10.3390/cancers11060801] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 04/23/2019] [Accepted: 04/26/2019] [Indexed: 12/12/2022] Open
Abstract
The risk of developing gastric cancer is strongly linked to Helicobacter pylori (H. pylori) infection. Alternatively, autophagy is a conserved response that is important in cellular homeostasis and provides protection against bacterial infections. Although H. pylori is typically considered an extracellular bacterium, several reports indicate that it internalizes, possibly to avoid exposure to antibiotics. Mechanisms by which H. pylori manipulates host cell autophagic processes remain unclear and, importantly, none of the available studies consider a role for the secreted H. pylori virulence factor gamma-glutamyltranspeptidase (HpGGT) in this context. Here, we identify HpGGT as a novel autophagy inhibitor in gastric cells. Our experiments revealed that deletion of HpGGT increased autophagic flux following H. pylori infection of AGS and GES-1 gastric cells. In AGS cells, HpGGT disrupted the late stages of autophagy by preventing degradation in lysosomes without affecting lysosomal acidification. Specifically, HpGGT impaired autophagic flux by disrupting lysosomal membrane integrity, which leads to a decrease in lysosomal cathepsin B activity. Moreover, HpGGT was necessary for efficient internalization of the bacteria into gastric cells. This important role of HpGGT in internalization together with the ability to inhibit autophagy posits HpGGT as a key virulence factor in the development of gastric cancer.
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Affiliation(s)
- Jimena Bravo
- Laboratory of Cellular Communication, Center for the Study of Exercise, Metabolism and Cancer (CEMC), Program in Cell and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile.
- Advanced Center for Chronic Diseases (ACCDiS), Santiago 8380492, Chile.
| | - Paula Díaz
- Laboratory of Cellular Communication, Center for the Study of Exercise, Metabolism and Cancer (CEMC), Program in Cell and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile.
- Advanced Center for Chronic Diseases (ACCDiS), Santiago 8380492, Chile.
| | - Alejandro H Corvalán
- Advanced Center for Chronic Diseases (ACCDiS), Santiago 8380492, Chile.
- Laboratory of Oncology, Department of Hematology and Oncology, Pontificia Universidad Católica de Chile, Santiago 8330034, Chile.
| | - Andrew F G Quest
- Laboratory of Cellular Communication, Center for the Study of Exercise, Metabolism and Cancer (CEMC), Program in Cell and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile.
- Advanced Center for Chronic Diseases (ACCDiS), Santiago 8380492, Chile.
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9
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Intracellular Degradation of Helicobacter pylori VacA Toxin as a Determinant of Gastric Epithelial Cell Viability. Infect Immun 2019; 87:IAI.00783-18. [PMID: 30692181 DOI: 10.1128/iai.00783-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/23/2019] [Indexed: 12/19/2022] Open
Abstract
Helicobacter pylori VacA is a secreted pore-forming toxin that induces cell vacuolation in vitro and contributes to the pathogenesis of gastric cancer and peptic ulcer disease. We observed that purified VacA has relatively little effect on the viability of AGS gastric epithelial cells, but the presence of exogenous weak bases such as ammonium chloride (NH4Cl) enhances the susceptibility of these cells to VacA-induced vacuolation and cell death. Therefore, we tested the hypothesis that NH4Cl augments VacA toxicity by altering the intracellular trafficking of VacA or inhibiting intracellular VacA degradation. We observed VacA colocalization with LAMP1- and LC3-positive vesicles in both the presence and absence of NH4Cl, indicating that NH4Cl does not alter VacA trafficking to lysosomes or autophagosomes. Conversely, we found that supplemental NH4Cl significantly increases the intracellular stability of VacA. By conducting experiments using chemical inhibitors, stable ATG5 knockdown cell lines, and ATG16L1 knockout cells (generated using CRISPR/Cas9), we show that VacA degradation is independent of autophagy and proteasome activity but dependent on lysosomal acidification. We conclude that weak bases like ammonia, potentially generated during H. pylori infection by urease and other enzymes, enhance VacA toxicity by inhibiting toxin degradation.
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10
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Saberi S, Pournasr B, Farzaneh Z, Esmaeili M, Hosseini ME, Baharvand H, Mohammadi M. A simple and cost-efficient adherent culture platform for human gastric primary cells, as an in vitro model for Helicobacter pylori infection. Helicobacter 2018; 23:e12489. [PMID: 29774633 DOI: 10.1111/hel.12489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Most two- dimensional in vitro models for studying host- H. pylori interactions rely on tumor-derived cell lines, which harbor malignant alterations. The recent development of human gastric organoids has overcome this limitation and provides a highly sophisticated, yet costly, short-term model for H. pylori infection, with restricted use in low-budget centers. METHOD Tissue specimens from upper, middle, and lower stomachs of H. pylori-negative volunteers were collectively dispersed and cultured on mouse embryonic fibroblast (MEF) or collagen-coated plates. Gastric primary cells (GPCs) were evaluated by light microscopy, immunostaining, qRT-PCR and ELISA analysis of cellular secretions, before and after H. pylori infection. RESULTS The formation and long-term (up to 1 year) maintenance of GPCs was highly dependent on adherent inactivated MEF cells, cultured in enriched media. These cells were multipassageable and able to undergo stable freezer storage and subsequent revival. The cellular composition of GPCs included the combination of cytokeratin 18 (CK18) and E-cadherin (E-cad)-positive epithelial cells, MUC5AC-positive gastric cells, and leucine-rich repeat containing G protein-coupled receptor 5 (LGR5)-positive progenitor cells. These cells produced significant amounts of gastric pepsinogens I and II. GPCs also allowed for extended (up to 96 hours) H. pylori infection, during which they underwent morphological alterations (cellular vacuolation and elongation) and hyperproduction of gastric pepsinogens and inflammatory cytokines (IL-8 and TNF-α). CONCLUSION We, hereby, present a simple, consistent, and cost-efficient gastric cell culture system, which provides a suitable model for extended in vitro infection of H. pylori. This platform can be employed for a variety of gastric-related research.
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Affiliation(s)
- Samaneh Saberi
- HPGC Research Group, Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran
| | - Behshad Pournasr
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Zahra Farzaneh
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Maryam Esmaeili
- HPGC Research Group, Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran
| | - Mahmoud Eshagh Hosseini
- Gastroenterology Department, Amiralam Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Baharvand
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.,Department of Developmental Biology, University of Science and Culture, Tehran, Iran
| | - Marjan Mohammadi
- HPGC Research Group, Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran
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11
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Helicobacter pylori γ-glutamyl transferase contributes to colonization and differential recruitment of T cells during persistence. Sci Rep 2017; 7:13636. [PMID: 29057967 PMCID: PMC5651840 DOI: 10.1038/s41598-017-14028-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/05/2017] [Indexed: 12/22/2022] Open
Abstract
Helicobacter pylori γ-glutamyl transferase (gGT) is a key bacterial virulence factor that is not only important for bacterial gastric colonization but also related to the development of gastric pathology. Despite accumulating evidence for pathogenic and immunologic functions of H. pylori gGT, it is still unclear how it supports gastric colonization and how its specific effects on the host’s innate and adaptive immune responses contribute to colonization and pathology. We have compared mice showing similar bacterial load after infection with gGT-proficient or gGT-deficient H. pylori to analyse the specific role of the enzyme during infection. Our data indicate that H. pylori gGT supports initial colonization. Nevertheless, bacteria lacking gGT can still colonize and persist. We observed that the presence of gGT during infection favoured a proinflammatory innate and adaptive immune response. Notably, H. pylori gGT activity was linked to increased levels of IFNγ, which were attributed to a differential recruitment of CD8+ T cells to the stomach. Our data support an essential role for H. pylori gGT in gastric colonization and further suggest that gGT favours infiltration of CD8+ cells to the gastric mucosa, which might play an important and yet overlooked role in the pathogenesis of H. pylori.
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12
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Al-Maleki AR, Loke MF, Lui SY, Ramli NSK, Khosravi Y, Ng CG, Venkatraman G, Goh KL, Ho B, Vadivelu J. Helicobacter pylori outer inflammatory protein A (OipA) suppresses apoptosis of AGS gastric cells in vitro. Cell Microbiol 2017; 19. [PMID: 28776327 DOI: 10.1111/cmi.12771] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 07/02/2017] [Accepted: 07/26/2017] [Indexed: 12/12/2022]
Abstract
Outer inflammatory protein A (OipA) is an important virulence factor associated with gastric cancer and ulcer development; however, the results have not been well established and turned out to be controversial. This study aims to elucidate the role of OipA in Helicobacter pylori infection using clinical strains harbouring oipA "on" and "off" motifs. Proteomics analysis was performed on AGS cell pre-infection and postinfection with H. pylori oipA "on" and "off" strains, using liquid chromatography/mass spectrometry. AGS apoptosis and cell cycle assays were performed. Moreover, expression of vacuolating cytotoxin A (VacA) was screened using Western blotting. AGS proteins that have been suggested previously to play a role or associated with gastric disease were down-regulated postinfection with oipA "off" strains comparing to oipA "on" strains. Furthermore, oipA "off" and ΔoipA cause higher level of AGS cells apoptosis and G0/G1 cell-cycle arrest than oipA "on" strains. Interestingly, deletion of oipA increased bacterial VacA production. The capability of H. pylori to induce apoptosis and suppress expression of proteins having roles in human disease in the absence of oipA suggests that strains not expressing OipA may be less virulent or may even be protective against carcinogenesis compared those expressing OipA. This potentially explains the higher incidence of gastric cancer in East Asia where oipA "on" strains predominates.
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Affiliation(s)
- Anis Rageh Al-Maleki
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mun Fai Loke
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Sook Yin Lui
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Nur Siti Khadijah Ramli
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yalda Khosravi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chow Goon Ng
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Gopinath Venkatraman
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khean-Lee Goh
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Bow Ho
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Singapore Precision Medicine Centre Pte Ltd, Singapore, Singapore
| | - Jamuna Vadivelu
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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