1
|
Altanbayar O, Amgalanbaatar A, Battogtokh C, Bayarjargal N, Belick D, Kohns Vasconcelos M, Mackenzie CR, Pfeffer K, Henrich B. Characterization of the cagA-gene in Helicobacter pylori in Mongolia and detection of two EPIYA-A enriched CagA types. Int J Med Microbiol 2022; 312:151552. [DOI: 10.1016/j.ijmm.2022.151552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 01/28/2022] [Accepted: 02/22/2022] [Indexed: 11/30/2022] Open
|
2
|
Oliveira AKS, Silva LLDL, Miguel MP, Blanco AJV, Carneiro LC, Barbosa MS. HELICOBACTER PYLORI cagA VIRULENCE GENE AND SEVERE ESOGASTRODUODENAL DISEASES: IS THERE AN ASSOCIATION? ARQUIVOS DE GASTROENTEROLOGIA 2021; 58:468-475. [PMID: 34909852 DOI: 10.1590/s0004-2803.202100000-85] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/05/2021] [Indexed: 01/01/2023]
Abstract
BACKGROUND Helicobacter pylori colonizes approximately half of the world's human population. Its presence in the gastric mucosa is associated with an increased risk of gastric adenocarcinoma, gastric lymphoma, and peptic ulcer disease. In Brazil, the high prevalence of H. pylori infection is a serious health problem. H. pylori virulence factors are associated with an increased risk of serious gastrointestinal disorders. The cagA gene encodes a cytotoxin-A-associated antigen (CagA) that is involved in bacterial pathogenicity. H. pylori strains carrying the cag pathogenicity island (cag-PAI) are significantly associated with severe clinical outcomes and histopathological changes. OBJECTIVE The present study aims to investigate the prevalence of the cagA gene among H. pylori isolates from patients with different gastric pathologies. Further, the study hopes to verify its association with clinical outcomes. In addition, phylogenetic analysis was performed on cagA-positive H. pylori strains from patients with severe and non-severe diseases. METHODS Gastric specimens were collected through a biopsy from 117 patients with different esogastroduodenal diseases. DNA was extracted from these gastric specimens and the polymerase chain reaction was performed to amplify the gene fragments corresponding to the 16S ribosomal RNA and cagA genes using specific primers. The polymerase chain reaction products of selected samples positive for cagA were sequenced. The sequences were aligned with reference sequences from the National Center for Biotechnology Information (NCBI) (Bethesda/USA), and a phylogenetic tree was constructed. RESULTS H. pylori was detected in 65.9% (77/117) of Brazilian patients with different gastroduodenal disorders. Overall, 80.5% (62/77) of the strains were cagA-positive. The ages of patients with cagA-positive strains (15 males and 47 females) ranged from 18 to 74 years. The lesions were categorized as non-severe and severe according to the endoscopic and histopathological reports the most prevalent non-severe esogastroduodenal lesion was gastritis 54/77 (70.12%), followed by esophagitis 12/77 (15.58%) and duodenitis 12/77 (15.58%). In contrast, the most prevalent severe lesions were atrophy 7/77 (9.09%), followed by metaplasia 3/77 (3.86%) and gastric adenocarcinoma 2/77 (2.59%). Phylogenetic analyses performed with the partial sequences of the cagA gene obtained from local strains were grouped in the same clade. No differences in phylogenetic distribution was detected between severe and non-severe diseases. CONCLUSION The cagA gene is highly prevalent among H. pylori isolates from gastric lesions in Brazilian patients. The presence of the cagA gene was not considered a marker of the severity of esogastroduodenal lesions in the present study. This is the first study to investigate the phylogenetic population structure of H. pylori strains in a Brazilian capital, which may improve our understanding of the clinical outcome of H. pylori infection.
Collapse
Affiliation(s)
| | | | - Marina Pacheco Miguel
- Universidade Federal de Goiás, Instituto de Patologia Tropical e Saúde Pública, Goiânia, GO, Brasil
| | | | - Lilian Carla Carneiro
- Universidade Federal de Goiás, Instituto de Patologia Tropical e Saúde Pública, Goiânia, GO, Brasil
| | - Mônica Santiago Barbosa
- Universidade Federal de Goiás, Núcleo de Estudos da Helicobacter pylori, Goiânia, GO, Brasil.,Universidade Federal de Goiás, Instituto de Patologia Tropical e Saúde Pública, Goiânia, GO, Brasil
| |
Collapse
|
3
|
HAYASHI HIROKI, INOUE JUN, OYAMA KATSUAKI, MATSUOKA KOKI, NISHIUMI SHIN, YOSHIDA MASARU, YANO YOSHIHIKO, KODAMA YUZO. Detection of Novel Amino Acid Polymorphisms in the East Asian CagA of Helicobacter Pylori with Full Sequencing Data. THE KOBE JOURNAL OF MEDICAL SCIENCES 2020; 66:E22-E31. [PMID: 32814754 PMCID: PMC7447099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 03/17/2020] [Indexed: 06/11/2023]
Abstract
Cytotoxin-associated gene A (CagA) is generally accepted to be the most important virulence factor of Helicobacter pylori and increases the risk of developing gastric cancer. East Asian CagA, which includes the EPIYA-D segment at the C-terminal region, has a significantly higher gastric carcinogenic rate than Western CagA including the EPIYA-C segment. Although the amino acid polymorphism surrounding the EPIYA motif in the C-terminal region has been examined in detail, limited information is currently available on the amino acid polymorphism of the N-terminal region of East Asian CagA. In the present study, we analyzed the sequencing data of East Asian CagA that we obtained previously to detect amino acid changes (AACs) in the N-terminal region of East Asian CagA. Four highly frequent AACs in the N-terminal region of East Asian CagA were detected in our datasets, two of which (V356A, Y677F) exhibited reproducible specificity using a validation dataset from the NCBI database, which are candidate AACs related to the pathogenic function of CagA. We examined whether these AACs affect the functions of CagA in silico model. The computational docking simulation model showed that binding affinity between CagA and phosphatidylserine remained unchanged in the model of mutant CagA reflecting both AAC, whereas that between CagA and α5β1 integrin significantly increased. Based on whole genome sequencing data we herein identified novel specific AACs in the N-terminal regions of EPIYA-D that have the potential to change the function of CagA.
Collapse
Affiliation(s)
- HIROKI HAYASHI
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - JUN INOUE
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - KATSUAKI OYAMA
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - KOKI MATSUOKA
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - SHIN NISHIUMI
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - MASARU YOSHIDA
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
- Division of Metabolomics Research, Department of Internal Related, Kobe University Graduate School of Medicine, Kobe, Japan
| | - YOSHIHIKO YANO
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
- Division of Molecular Medicine & Medical Genetics, Department of Pathology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - YUZO KODAMA
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| |
Collapse
|
4
|
Tegtmeyer N, Ghete TD, Schmitt V, Remmerbach T, Cortes MCC, Bondoc EM, Graf HL, Singer BB, Hirsch C, Backert S. Type IV secretion of Helicobacter pylori CagA into oral epithelial cells is prevented by the absence of CEACAM receptor expression. Gut Pathog 2020; 12:25. [PMID: 32435278 PMCID: PMC7222478 DOI: 10.1186/s13099-020-00363-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 05/09/2020] [Indexed: 02/07/2023] Open
Abstract
Background Helicobacter pylori typically colonizes the human stomach, but it can occasionally be detected in the oral cavity of infected persons. Clinical outcome as a result of gastric colonization depends on presence of the pathogenicity island cagPAI that encodes a type-IV secretion system (T4SS) for translocation of the effector protein CagA and ADP-heptose. Upon injection into target cells, CagA is phosphorylated, which can be demonstrated by in vitro infection of the gastric epithelial cell line AGS, resulting in cell elongation. Here we investigated whether H. pylori can exert these responses during interaction with cells from the oral epithelium. To this purpose, three oral epithelial cell lines, HN, CAL-27 and BHY, were infected with various virulent wild-type H. pylori strains, and CagA delivery and ADP-heptose-mediated pro-inflammatory responses were monitored. Results All three oral cell lines were resistant to elongation upon infection, despite similar bacterial binding capabilities. Moreover, T4SS-dependent CagA injection was absent. Resistance to CagA delivery was shown to be due to absence of CEACAM expression in these cell lines, while these surface molecules have recently been recognized as H. pylori T4SS receptors. Lack of CEACAM expression in HN, CAL-27 and BHY cells was overcome by genetic introduction of either CEACAM1, CEACAM5, or CEACAM6, which in each of the cell lines was proven sufficient to facilitate CagA delivery and phosphorylation upon H. pylori infection to levels similar to those observed with the gastric AGS cells. Pro-inflammatory responses, as measured by interleukin-8 ELISA, were induced to high levels in each cell line and CEACAM-independent. Conclusions These results show that lack of CEACAM receptors on the surface of the oral epithelial cells was responsible for resistance to H. pylori CagA-dependent pathogenic activities, and confirms the important role for the T4SS-dependent interaction of these receptors with H. pylori in the gastric epithelium.
Collapse
Affiliation(s)
- Nicole Tegtmeyer
- 1Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen, Staudtstrasse 5, 91058 Erlangen, Germany
| | - Tabita Denisia Ghete
- 1Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen, Staudtstrasse 5, 91058 Erlangen, Germany
| | - Verena Schmitt
- 2Medical Faculty, Institute of Anatomy, University of Duisburg-Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Torsten Remmerbach
- 3Division of Clinical and Experimental Oral Medicine, Department of OMF-Surgery, Leipzig University Hospital, University of Leipzig, Leipzig, Germany
| | - Maria Celeste C Cortes
- 4Center for Basic Science Research (CBSR), Research and Biotechnology (R&B), St. Luke's Medical Center, Quezon City, Philippines
| | - Edgardo M Bondoc
- 5Institute for Digestive and Liver Diseases, St. Luke's Medical Center, Quezon City, Philippines
| | - Hans-Ludwig Graf
- 6Department of Oral, Maxillary, Facial and Reconstructive Plastic Surgery, University Hospital of Leipzig, Leipzig, Germany
| | - Bernhard B Singer
- 2Medical Faculty, Institute of Anatomy, University of Duisburg-Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Christian Hirsch
- 7Department of Paediatric Dentistry, University School of Dental Medicine, University of Leipzig, Leipzig, Germany
| | - Steffen Backert
- 1Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen, Staudtstrasse 5, 91058 Erlangen, Germany
| |
Collapse
|
5
|
Ansari S, Akada J, Matsuo Y, Shiota S, Kudo Y, Okimoto T, Murakami K, Yamaoka Y. Epitope peptides of Helicobacter pylori CagA antibodies from sera by whole-peptide mapping. J Gastroenterol 2019; 54:1039-1051. [PMID: 31049715 PMCID: PMC6824978 DOI: 10.1007/s00535-019-01584-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 04/22/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND Helicobacter pylori CagA has been found to be immuno-dominant protein and utilized for the diagnosis of the infection with cagA-positive strains. It is important to characterize the peptide epitopes capable of detecting serum anti-CagA antibodies to understand CagA immunogenicity. METHODS Sera from 171 Japanese patients were subjected for the epitope mapping study. Eighty seven peptides were designed from the CagA consensus sequence and were used for ELISA protocol to test the serum samples. The reacting anti-CagA IgG amounts to specific peptides were measured and compared. RESULTS The study revealed a strong reactivity of two peptides (c7-NNTEPIYAQVNKKKAGQAT and c8-AGQATSPEEPIYAQVAKKV) in H. pylori-infected group. Interestingly, these two peptides contained the well-known EPIYA-A and EPIYA-B region, respectively, which are two out of three CagA phosphorylation domains. Tyrosine-phosphorylation of these peptides reduced their reactivity in most sera. Moreover, additional peptides' mapping and chimeric-peptides' experiments indicated that the amino acids (QV and KK) accommodated in right-side flanking regions of both EPIYA-motifs were essential for their strong reactivity, whereas the third EPIYA-motif containing peptide (c12-GRSASPEPIYATIDFDEA) with differing flanking amino acids was not reactive in most cases. CONCLUSIONS Our results suggest that the amino acid sequences constituted in the two reactive peptides are the important immunogenic regions of CagA which would be useful to develop next-generation peptide-based diagnostic assays.
Collapse
Affiliation(s)
- Shamshul Ansari
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka, Hasama-machi, Yufu-city, Oita 879-5593, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka, Hasama-machi, Yufu-city, Oita 879-5593, Japan
| | - Yuichi Matsuo
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka, Hasama-machi, Yufu-city, Oita 879-5593, Japan,Department of Host-Defense Biochemistry, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Seiji Shiota
- Department of General Medicine, Almeida Memorial Hospital, Oita, Japan
| | - Yoko Kudo
- Department of Gastroenterology, Oita University Faculty of Medicine, Yufu, Japan
| | - Tadayoshi Okimoto
- Department of Gastroenterology, Oita University Faculty of Medicine, Yufu, Japan
| | - Kazunari Murakami
- Department of Gastroenterology, Oita University Faculty of Medicine, Yufu, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka, Hasama-machi, Yufu-city, Oita 879-5593, Japan,Global Oita Medical Advanced Research Center for Health, Idaigaoka, Hasama-machi, Yufu-city, Oita 879-5593, Japan,Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, 2002 Holcombe Blvd. Houston, Texas 77030, USA
| |
Collapse
|
6
|
Pachathundikandi SK, Gutiérrez-Escobar AJ, Tegtmeyer N. Tailor-Made Detection of Individual Phosphorylated and Non-Phosphorylated EPIYA-Motifs of Helicobacter pylori Oncoprotein CagA. Cancers (Basel) 2019; 11:cancers11081163. [PMID: 31412675 PMCID: PMC6721621 DOI: 10.3390/cancers11081163] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 07/25/2019] [Accepted: 08/08/2019] [Indexed: 02/07/2023] Open
Abstract
The gastric pathogen and carcinogen Helicobacter pylori(H. pylori) encodes a type IV secretion system for translocation of the effector protein CagA into host cells. Injected CagA becomes tyrosine-phosphorylated at the five amino acid residue Glutamate-Proline- Isoleucine-Tyrosine-Alanine (EPIYA)-sequence motifs. These phosphorylated EPIYA-sites represent recognition motifs for binding of multiple host factors, which then manipulate signaling pathways to trigger gastric disease. Thus, efficient detection of single phosphorylated EPIYA-motifs in CagA is required. Detection of phospho-CagA is primarily performed using commercial pan-phosphotyrosine antibodies. However, those antibodies were originally generated to recognize many phosphotyrosines in various mammalian proteins and are not optimized for use in bacteria. To address this important limitation, we synthesized 11-mer phospho- and non-phospho-peptides from EPIYA-motifs A, B, and C, and produced three phospho-specific and three non-phospho-specific rabbit polyclonal CagA antibodies. These antibodies specifically recognized the corresponding phosphorylated and non-phosphorylated EPIYA-motifs, while the EPIYA-C antibodies also recognized the related East-Asian EPIYA-D motif. Otherwise, no cross-reactivity of the antibodies among EPIYAs was observed. Western blotting demonstrated that each EPIYA-motif can be predominantly phosphorylated during H. pylori infection. This represents the first complete set of phospho-specific antibodies for an effector protein in bacteria, providing useful tools to gather information for the categorization of CagA phosphorylation, cancer signaling, and gastric disease progression.
Collapse
Affiliation(s)
- Suneesh Kumar Pachathundikandi
- Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstraße 5, D-91058 Erlangen, Germany
| | - Andrés Julián Gutiérrez-Escobar
- Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstraße 5, D-91058 Erlangen, Germany
| | - Nicole Tegtmeyer
- Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstraße 5, D-91058 Erlangen, Germany.
| |
Collapse
|
7
|
Buß M, Tegtmeyer N, Schnieder J, Dong X, Li J, Springer TA, Backert S, Niemann HH. Specific high affinity interaction of Helicobacter pylori CagL with integrin α V β 6 promotes type IV secretion of CagA into human cells. FEBS J 2019; 286:3980-3997. [PMID: 31197920 DOI: 10.1111/febs.14962] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 04/12/2019] [Accepted: 06/10/2019] [Indexed: 12/21/2022]
Abstract
CagL is an essential pilus surface component of the virulence-associated type IV secretion system (T4SS) employed by Helicobacter pylori to translocate the oncogenic effector protein CagA into human gastric epithelial cells. CagL contains an RGD motif and integrin α5 β1 is widely accepted as its host cell receptor. Here, we show that CagL binds integrin αV β6 with substantially higher affinity and that this interaction is functionally important. Cell surface expression of αV β6 on various cell lines correlated perfectly with cell adhesion to immobilized CagL and with binding of soluble CagL to cells. We found no such correlation for α5 β1 . The purified αV β6 ectodomain bound CagL with high affinity. This interaction was highly specific, as the affinity of CagL for other RGD-binding integrins was two to three orders of magnitude weaker. Mutation of either conserved leucine in the CagL RGDLXXL motif, a motif that generally confers specificity for integrin αV β6 and αV β8 , lowered the affinity of CagL for αV β6 . Stable expression of αV β6 in αV β6 -negative but α5 β1 -expressing human cells promoted two hallmarks of the functional H. pylori T4SS, namely translocation of CagA into host cells and induction of interleukin-8 secretion by host cells. These findings suggest that integrin αV β6 , although not essential for T4SS function, represents an important host cell receptor for CagL.
Collapse
Affiliation(s)
- Maren Buß
- Structural Biochemistry, Department of Chemistry, Bielefeld University, Germany
| | - Nicole Tegtmeyer
- Division of Microbiology, Department of Biology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany
| | - Jennifer Schnieder
- Structural Biochemistry, Department of Chemistry, Bielefeld University, Germany
| | - Xianchi Dong
- Children's Hospital Boston, MA, USA.,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Jing Li
- Children's Hospital Boston, MA, USA.,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Timothy A Springer
- Children's Hospital Boston, MA, USA.,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany
| | - Hartmut H Niemann
- Structural Biochemistry, Department of Chemistry, Bielefeld University, Germany
| |
Collapse
|
8
|
Falkeis-Veits C, Vieth M. Non-malignant Helicobacter pylori-Associated Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1149:121-134. [PMID: 31016630 DOI: 10.1007/5584_2019_362] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Helicobacter pylori infection of the human stomach is associated with chronic gastritis, peptic ulcer disease or gastric carcinoma, and thus a high burden for the public health systems worldwide. Fortunately, only a small subfraction of up to 15-20% of infected individuals will develop serious complications. Unfortunately, it is not always known upfront, who will be affected by serious diesease outcome. For risk stratifications, it is therefore necessary to establish a common terminology and grading system, that can be applied worldwide to compare population data. The updated Sydney System for classification of gastritis with its semi-quantitative analogue scale is the system, that is currently used worldwide. Additionally, pathologists should always try to classify the etiology of the inflammatory infiltrates in the stomach to instruct the clinicians for choosing a proper treatment regime. Risk factors such as intestinal metaplasia, atrophy and scoring systems to classify these risk factors into a clinical context such as OLGA and OLGIM are discussed. Also, special forms of gastritis like lymphocytic gastritis, autoimmune gastritis and peptic ulcer disease are explained and discussed e.g. how to diagnose and how to treat. Extra-gastric sequelae of H. pylori infections inside and outside the stomach are shown in this chapter as well. Important host and bacterial risk factors such as pathogenicity islands are dicussed to draw a complete landscape around a H. pylori infection, that still can be diagnosed in patients. However, it needs to be noted that some countries have almost no H. pylori infection anymore, while others have still a very high frequency of infections with or without serious complications. The understanding and application of risk assessements may help to save money and quality of life. Extra-gastric H. pylori infections are rarely reported in the literature until today. The pathogenitiy is still under debate, but especially in the bile ducts and gallbladder, several pathological conditions may be also based on H. pylori infection, and will be also discussed.
Collapse
Affiliation(s)
| | - Michael Vieth
- Institute of Pathology, Klinikum Bayreuth, Bayreuth, Germany.
| |
Collapse
|
9
|
Genetic Polymorphisms in Inflammatory and Other Regulators in Gastric Cancer: Risks and Clinical Consequences. Curr Top Microbiol Immunol 2019; 421:53-76. [PMID: 31123885 DOI: 10.1007/978-3-030-15138-6_3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Helicobacter pylori infection is associated with the development of a chronic inflammatory response, which may induce peptic ulcers, gastric cancer (GC), and mucosa-associated lymphoid tissue (MALT) lymphoma. Chronic H. pylori infection promotes the genetic instability of gastric epithelial cells and interferes with the DNA repair systems in host cells. Colonization of the stomach with H. pylori is an important cause of non-cardia GC and gastric MALT lymphoma. The reduction of GC development in patients who underwent anti-H. pylori eradication schemes has also been well described. Individual susceptibility to GC development depends on the host's genetic predisposition, H. pylori virulence factors, environmental conditions, and geographical determinants. Biological determinants are urgently sought to predict the clinical course of infection in individuals with confirmed H. pylori infection. Possible candidates for such biomarkers include genetic aberrations such as single-nucleotide polymorphisms (SNPs) found in various cytokines/growth factors (e.g., IL-1β, IL-2, IL-6, IL-8, IL-10, IL-13, IL-17A/B, IFN-γ, TNF, TGF-β) and their receptors (IL-RN, TGFR), innate immunity receptors (TLR2, TLR4, CD14, NOD1, NOD2), enzymes involved in signal transduction cascades (PLCE1, PKLR, PRKAA1) as well as glycoproteins (MUC1, PSCA), and DNA repair enzymes (ERCC2, XRCC1, XRCC3). Bacterial determinants related to GC development include infection with CagA-positive (particularly with a high number of EPIYA-C phosphorylation motifs) and VacA-positive isolates (in particular s1/m1 allele strains). The combined genotyping of bacterial and host determinants suggests that the accumulation of polymorphisms favoring host and bacterial features increases the risk for precancerous and cancerous lesions in patients.
Collapse
|
10
|
Javed S, Skoog EC, Solnick JV. Impact of Helicobacter pylori Virulence Factors on the Host Immune Response and Gastric Pathology. Curr Top Microbiol Immunol 2019; 421:21-52. [PMID: 31123884 DOI: 10.1007/978-3-030-15138-6_2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Helicobacter pylori chronically infects nearly half the world's population, yet most of those infected remain asymptomatic throughout their lifetime. The outcome of infection-peptic ulcer disease or gastric cancer versus asymptomatic colonization-is a product of host genetics, environmental influences, and differences in bacterial virulence factors. Here, we review the current understanding of the cag pathogenicity island (cagPAI), the vacuolating cytotoxin (VacA), and a large family of outer membrane proteins (OMPs), which are among the best understood H. pylori virulence determinants that contribute to disease. Each of these virulence factors is characterized by allelic and phenotypic diversity that is apparent within and across individuals, as well as over time, and modulates inflammation. From the bacterial perspective, inflammation is probably a necessary evil because it promotes nutrient acquisition, but at the cost of reduction in bacterial load and therefore decreases the chance of transmission to a new host. The general picture that emerges is one of a chronic bacterial infection that is dependent on both inducing and carefully regulating the host inflammatory response. A better understanding of these regulatory mechanisms may have implications for the control of chronic inflammatory diseases that are increasingly common causes of human morbidity and mortality.
Collapse
Affiliation(s)
- Sundus Javed
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA.,Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan
| | - Emma C Skoog
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA
| | - Jay V Solnick
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA. .,Center for Comparative Medicine, University of California, Davis, Davis, CA, 95616, USA.
| |
Collapse
|
11
|
Tegtmeyer N, Harrer A, Schmitt V, Singer BB, Backert S. Expression of CEACAM1 or CEACAM5 in AZ-521 cells restores the type IV secretion deficiency for translocation of CagA byHelicobacter pylori. Cell Microbiol 2018; 21:e12965. [DOI: 10.1111/cmi.12965] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 10/04/2018] [Accepted: 10/08/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Nicole Tegtmeyer
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen; Erlangen Germany
| | - Aileen Harrer
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen; Erlangen Germany
| | - Verena Schmitt
- Medical Faculty, Institute of Anatomy; University of Duisburg-Essen; Essen Germany
| | - Bernhard B. Singer
- Medical Faculty, Institute of Anatomy; University of Duisburg-Essen; Essen Germany
| | - Steffen Backert
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen; Erlangen Germany
| |
Collapse
|
12
|
Dyer V, Brüggemann H, Sörensen M, Kühl AA, Hoffman K, Brinkmann V, Reines MDM, Zimmerman S, Meyer TF, Koch M. Genomic features of the Helicobacter pylori strain PMSS1 and its virulence attributes as deduced from its in vivo colonisation patterns. Mol Microbiol 2018; 110:761-776. [PMID: 30230643 DOI: 10.1111/mmi.14123] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 08/27/2018] [Accepted: 09/05/2018] [Indexed: 12/19/2022]
Abstract
The human gastric pathogen Helicobacter pylori occurs in two basic variants, either exhibiting a functional cagPAI-encoded type-4-secretion-system (T4SS) or not. Only a few cagPAI-positive strains have been successfully adapted for long-term infection of mice, including the pre-mouse Sydney strain 1 (PMSS1). Here we confirm that PMSS1 induces gastric inflammation and neutrophil infiltration in mice, progressing to intestinal metaplasia. Complete genome analysis of PMSS1 revealed 1,423 coding sequences, encompassing the cagPAI gene cluster and, unusually, the location of the cytotoxin-associated gene A (cagA) approximately 15 kb downstream of the island. PMSS1 harbours three genetically exchangeable loci that are occupied by the hopQ coding sequences. HopQ represents a critical co-factor required for the translocation of CagA into the host cell and activation of NF-κB via the T4SS. Long-term colonisation of mice led to an impairment of cagPAI functionality. One of the bacterial clones re-isolated at four months post-infection revealed a mutation in the cagPAI gene cagW, resulting in a frame shift mutation, which prevented CagA translocation, possibly due to an impairment of T4SS function. Rescue of the mutant cagW re-established CagA translocation. Our data reveal intriguing insights into the adaptive abilities of PMSS1, suggesting functional modulation of the H. pylori cagPAI virulence attribute.
Collapse
Affiliation(s)
- Victoria Dyer
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Holger Brüggemann
- Department of Biomedicine, Aarhus University, Aarhus C, 8000, Denmark
| | - Meike Sörensen
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Anja A Kühl
- Division of Gastroenterology, Infectiology and Rheumatology, Medical Department, Campus Benjamin Franklin, Charité, Berlin, 12200, Germany
| | - Kirstin Hoffman
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Volker Brinkmann
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Maria Del Mar Reines
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Stephanie Zimmerman
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Thomas F Meyer
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| | - Manuel Koch
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, 10117, Germany
| |
Collapse
|
13
|
Tegtmeyer N, Wessler S, Necchi V, Rohde M, Harrer A, Rau TT, Asche CI, Boehm M, Loessner H, Figueiredo C, Naumann M, Palmisano R, Solcia E, Ricci V, Backert S. Helicobacter pylori Employs a Unique Basolateral Type IV Secretion Mechanism for CagA Delivery. Cell Host Microbe 2018; 22:552-560.e5. [PMID: 29024645 DOI: 10.1016/j.chom.2017.09.005] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 07/26/2017] [Accepted: 09/08/2017] [Indexed: 01/16/2023]
Abstract
The Helicobacter pylori (Hp) type IV secretion system (T4SS) forms needle-like pili, whose binding to the integrin-β1 receptor results in injection of the CagA oncoprotein. However, the apical surface of epithelial cells is exposed to Hp, whereas integrins are basolateral receptors. Hence, the mechanism of CagA delivery into polarized gastric epithelial cells remains enigmatic. Here, we demonstrate that T4SS pilus formation during infection of polarized cells occurs predominantly at basolateral membranes, and not at apical sites. Hp accomplishes this by secreting another bacterial protein, the serine protease HtrA, which opens cell-to-cell junctions through cleaving epithelial junctional proteins including occludin, claudin-8, and E-cadherin. Using a genetic system expressing a peptide inhibitor, we demonstrate that HtrA activity is necessary for paracellular transmigration of Hp across polarized cell monolayers to reach basolateral membranes and inject CagA. The contribution of this unique signaling cascade to Hp pathogenesis is discussed.
Collapse
Affiliation(s)
- Nicole Tegtmeyer
- Department of Biology, Division of Microbiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Silja Wessler
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Vittorio Necchi
- Pathologic Anatomy and Human Physiology Units and Centro Grandi Strumenti, University of Pavia and Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Manfred Rohde
- Helmholtz Centre for Infection Research, Microscopy Unit, Braunschweig, Germany
| | - Aileen Harrer
- Department of Biology, Division of Microbiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Tilman T Rau
- Institute of Pathology, University of Erlangen-Nuremberg, Erlangen, Germany; Institute of Pathology, University of Bern, Bern, Switzerland
| | - Carmen Isabell Asche
- Department of Biology, Division of Microbiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Manja Boehm
- Department of Biology, Division of Microbiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Holger Loessner
- Paul Ehrlich Institute, Department of Microbiology, Langen, Germany
| | - Ceu Figueiredo
- University of Porto, i3S, IPATIMUP, Faculty of Medicine, Porto, Portugal
| | - Michael Naumann
- Otto von Guericke University, Institute of Experimental Internal Medicine, Magdeburg, Germany
| | - Ralf Palmisano
- Optical Imaging Centre, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Enrico Solcia
- Pathologic Anatomy and Human Physiology Units and Centro Grandi Strumenti, University of Pavia and Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Vittorio Ricci
- Pathologic Anatomy and Human Physiology Units and Centro Grandi Strumenti, University of Pavia and Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Steffen Backert
- Department of Biology, Division of Microbiology, University of Erlangen-Nuremberg, Erlangen, Germany.
| |
Collapse
|
14
|
Unusual Manifestation of Live Staphylococcus saprophyticus, Corynebacterium urinapleomorphum, and Helicobacter pylori in the Gallbladder with Cholecystitis. Int J Mol Sci 2018; 19:ijms19071826. [PMID: 29933576 PMCID: PMC6073424 DOI: 10.3390/ijms19071826] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/08/2018] [Accepted: 06/15/2018] [Indexed: 12/13/2022] Open
Abstract
Culture-independent studies have identified DNA of bacterial pathogens in the gallbladder under pathological conditions, yet reports on the isolation of corresponding live bacteria are rare. Thus, it is unclear which pathogens, or pathogen communities, can colonize the gallbladder and cause disease. Using light microscopy, scanning electron microscopy, culture techniques, phylogenetic analysis, urease assays and Western blotting, we investigated the presence of live bacterial communities in the gallbladder of a cholecystitis patient after cholecystectomy. 16S rRNA gene sequencing of isolated bacterial colonies revealed the presence of pathogens most closely resembling Corynebacterium urinapleomorphum nov. sp., Staphylococcus saprophyticus and Helicobacter pylori. The latter colonies were confirmed as H. pylori by immunohistochemistry and biochemical methods. H. pylori cultured from the gallbladder exhibited both the same DNA fingerprinting and Western cagA gene sequence with ABC-type EPIYA (Glu-Pro-Ile-Tyr-Ala) phosphorylation motifs as isolates recovered from the gastric mucus of the same patient, suggesting that gastric H. pylori can also colonize other organs in the human body. Taken together, here we report, for the first time, the identification and characterization of a community consisting of live S. saprophyticus; C. urinapleomorphum, and H. pylori in the gallbladder of a patient with acute cholecystitis. Their potential infection routes and roles in pathogenesis are discussed.
Collapse
|
15
|
Yuan XY, Wang Y, Wang MY. The type IV secretion system in Helicobacter pylori. Future Microbiol 2018; 13:1041-1054. [PMID: 29927340 DOI: 10.2217/fmb-2018-0038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Helicobacter pylori (H. pylori) has an essential role in the pathogenesis of gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue lymphoma and gastric cancer. The severity of the host inflammatory responses against the bacteria have been straightly associated with a special bacterial virulence factor, the cag pathogenicity island, which is a type IV secretion system (T4SS) to deliver CagA into the host cells. Besides cag-T4SS, the chromosomes of H. pylori can encode another three T4SSs, including comB, tfs3 and tfs4. In this review, we systematically reviewed the four T4SSs of H. pylori and explored their roles in the pathogenesis of gastroduodenal diseases. The information summarized in this review might provide valuable insights into the pathogenic mechanism for H. pylori.
Collapse
Affiliation(s)
- Xiao-Yan Yuan
- Department of Central Lab, Weihai Municipal Hospital Affiliated to Dalian Medical University, Weihai, Shandong, 264200, PR China
| | - Ying Wang
- Department of Central Lab, Weihai Municipal Hospital Affiliated to Dalian Medical University, Weihai, Shandong, 264200, PR China
| | - Ming-Yi Wang
- Department of Central Lab, Weihai Municipal Hospital Affiliated to Dalian Medical University, Weihai, Shandong, 264200, PR China
| |
Collapse
|
16
|
Backert S, Haas R, Gerhard M, Naumann M. The Helicobacter pylori Type IV Secretion System Encoded by the cag Pathogenicity Island: Architecture, Function, and Signaling. Curr Top Microbiol Immunol 2018. [DOI: 10.1007/978-3-319-75241-9_8] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
17
|
Pachathundikandi SK, Backert S. Helicobacter pylori controls NLRP3 expression by regulating hsa-miR-223-3p and IL-10 in cultured and primary human immune cells. Innate Immun 2017; 24:11-23. [PMID: 29145789 DOI: 10.1177/1753425917738043] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Inflammasome-mediated production of mature IL-1β and IL-18 cytokines represents an important innate immune response against infecting pathogens. Helicobacter pylori, one of the most successful and persistent human pathogens, induces severe inflammation leading to gastritis and more serious gastric diseases. H. pylori modulates different immune responses for its survival and inflammasome signaling is manipulated by the cag pathogenicity island ( cagPAI), urease and VacA cytotoxin. Here we report that H. pylori regulates NLRP3 expression, an inflammasome forming regulator, in infected THP-1 monocytes. This response was independent of the major H. pylori pathogenicity-associated factors CagA, VacA, Cgt, FlaA and cagPAI. Two NLRP3 expression controlling factors, the NLRP3 mRNA targeting microRNA hsa-miR-223-3p and cytokine IL-10, were found to work in tandem for its regulation. H. pylori infection also induced copious amount of pro-IL-1β in THP-1 monocytes/macrophages but secreted a very low amount of mature IL-1β. Moreover, secreted IL-10 correlated with the down-regulation of nigericin-induced NLRP3 inflammasome activation of LPS-primed THP-1 monocytes and human PBMCs from volunteers. However, H. pylori-treated PBMCs secreted significantly more mature IL-1β throughout the infection period, which suggests a different mode of activation. Taken together, this study demonstrates targeting of inflammasome-forming NLRP3, an important innate immunity component, and crucial manipulation of pro- and anti-inflammatory cytokines in H. pylori infection.
Collapse
Affiliation(s)
| | - Steffen Backert
- Division of Microbiology, Department of Biology, 98885 Friedrich Alexander University , Erlangen, Germany
| |
Collapse
|
18
|
Harrer A, Boehm M, Backert S, Tegtmeyer N. Overexpression of serine protease HtrA enhances disruption of adherens junctions, paracellular transmigration and type IV secretion of CagA by Helicobacter pylori. Gut Pathog 2017; 9:40. [PMID: 28770008 PMCID: PMC5526239 DOI: 10.1186/s13099-017-0189-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 07/11/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The serine protease HtrA is an important factor for regulating stress responses and protein quality control in bacteria. In recent studies, we have demonstrated that the gastric pathogen Helicobacter pylori can secrete HtrA into the extracellular environment, where it cleaves-off the ectodomain of the tumor suppressor and adherens junction protein E-cadherin on gastric epithelial cells. RESULTS E-cadherin cleavage opens cell-to-cell junctions, allowing paracellular transmigration of the bacteria across polarized monolayers of MKN-28 and Caco-2 epithelial cells. However, rapid research progress on HtrA function is mainly hampered by the lack of ΔhtrA knockout mutants, suggesting that htrA may represent an essential gene in H. pylori. To circumvent this major handicap and to investigate the role of HtrA further, we overexpressed HtrA by introducing a second functional htrA gene copy in the chromosome and studied various virulence properties of the bacteria. The resulting data demonstrate that overexpression of HtrA in H. pylori gives rise to elevated rates of HtrA secretion, cleavage of E-cadherin, bacterial transmigration and delivery of the type IV secretion system (T4SS) effector protein CagA into polarized epithelial cells, but did not affect IL-8 chemokine production or the secretion of vacuolating cytotoxin VacA and γ-glutamyl-transpeptidase GGT. CONCLUSIONS These data provide for the first time genetic evidence in H. pylori that HtrA is a novel major virulence factor controlling multiple pathogenic activities of this important microbe.
Collapse
Affiliation(s)
- Aileen Harrer
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany
| | - Manja Boehm
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany
| | - Steffen Backert
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany
| | - Nicole Tegtmeyer
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany
| |
Collapse
|
19
|
The Human Stomach in Health and Disease: Infection Strategies by Helicobacter pylori. Curr Top Microbiol Immunol 2017; 400:1-26. [PMID: 28124147 DOI: 10.1007/978-3-319-50520-6_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori is a bacterial pathogen which commonly colonizes the human gastric mucosa from early childhood and persists throughout life. In the vast majority of cases, the infection is asymptomatic. H. pylori is the leading cause of peptic ulcer disease and gastric cancer, however, and these outcomes occur in 10-15% of those infected. Gastric adenocarcinoma is the third most common cause of cancer-associated death, and peptic ulcer disease is a significant cause of morbidity. Disease risk is related to the interplay of numerous bacterial host and environmental factors, many of which influence chronic inflammation and damage to the gastric mucosa. This chapter summarizes what is known about health and disease in H. pylori infection, and highlights the need for additional research in this area.
Collapse
|
20
|
Structural Insights into Helicobacter pylori Cag Protein Interactions with Host Cell Factors. Curr Top Microbiol Immunol 2017; 400:129-147. [PMID: 28124152 DOI: 10.1007/978-3-319-50520-6_6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The most virulent strains of Helicobacter pylori carry a genomic island (cagPAI) containing a set of 27-31 genes. The encoded proteins assemble a syringe-like apparatus to inject the cytotoxin-associated gene A (CagA) protein into gastric cells. This molecular device belongs to the type IV secretion system (T4SS) family albeit with unique characteristics. The cagPAI-encoded T4SS and its effector protein CagA have an intricate relationship with the host cell, with multiple interactions that only start to be deciphered from a structural point of view. On the one hand, the major roles of the interactions between CagL and CagA (and perhaps CagI and CagY) and host cell factors are to facilitate H. pylori adhesion and to mediate the injection of the CagA oncoprotein. On the other hand, CagA interactions with host cell partners interfere with cellular pathways to subvert cell defences and to promote H. pylori infection. Although a clear mechanism for CagA translocation is still lacking, the structural definition of CagA and CagL domains involved in interactions with signalling proteins are progressively coming to light. In this chapter, we will focus on the structural aspects of Cag protein interactions with host cell molecules, critical molecular events precluding H. pylori-mediated gastric cancer development.
Collapse
|
21
|
Tegtmeyer N, Neddermann M, Asche CI, Backert S. Subversion of host kinases: a key network in cellular signaling hijacked byHelicobacter pyloriCagA. Mol Microbiol 2017; 105:358-372. [DOI: 10.1111/mmi.13707] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Nicole Tegtmeyer
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen-Nuremberg; Staudtstr. 5 Erlangen D-91058 Germany
| | - Matthias Neddermann
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen-Nuremberg; Staudtstr. 5 Erlangen D-91058 Germany
| | - Carmen Isabell Asche
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen-Nuremberg; Staudtstr. 5 Erlangen D-91058 Germany
| | - Steffen Backert
- Department of Biology, Division of Microbiology; Friedrich Alexander University Erlangen-Nuremberg; Staudtstr. 5 Erlangen D-91058 Germany
| |
Collapse
|
22
|
Bernardini G, Figura N, Ponzetto A, Marzocchi B, Santucci A. Application of proteomics to the study of Helicobacter pylori and implications for the clinic. Expert Rev Proteomics 2017; 14:477-490. [PMID: 28513226 DOI: 10.1080/14789450.2017.1331739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Helicobacter pylori (H. pylori) is a gram-negative bacterium that colonizes the gastric epithelium and mucous layer of more than half the world's population. H. pylori is a primary human pathogen, responsible for the development of chronic gastritis, peptic ulceration and gastric cancer. Proteomics is impacting several aspects of medical research: understanding the molecular basis of infection and disease manifestation, identification of therapeutic targets and discovery of clinically relevant biomarkers. Areas covered: The main aim of the present review is to provide a comprehensive overview of the contribution of proteomics to the study of H. pylori infection pathophysiology. In particular, we focused on the role of the bacterium and its most important virulence factor, CagA, in the progression of gastric cells transformation and cancer progression. We also discussed the proteomic approaches aimed at the investigation of the host response to bacterial infection. Expert commentary: In the field of proteomics of H. pylori, comprehensive analysis of clinically relevant proteins (functional proteomics) rather than entire proteomes will result in important medical outcomes. Finally, we provided an outlook on the potential development of proteomics in H. pylori research.
Collapse
Affiliation(s)
- Giulia Bernardini
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| | - Natale Figura
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| | - Antonio Ponzetto
- b Dipartimento di Scienze Mediche , Università degli Studi di Torino , Torino , Italy
| | - Barbara Marzocchi
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| | - Annalisa Santucci
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| |
Collapse
|
23
|
Backert S, Tegtmeyer N. Type IV Secretion and Signal Transduction of Helicobacter pylori CagA through Interactions with Host Cell Receptors. Toxins (Basel) 2017; 9:E115. [PMID: 28338646 PMCID: PMC5408189 DOI: 10.3390/toxins9040115] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 03/20/2017] [Accepted: 03/22/2017] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori is a highly successful human bacterium, which is exceptionally equipped to persistently inhabit the human stomach. Colonization by this pathogen is associated with gastric disorders ranging from chronic gastritis and peptic ulcers to cancer. Highly virulent H. pylori strains express the well-established adhesins BabA/B, SabA, AlpA/B, OipA, and HopQ, and a type IV secretion system (T4SS) encoded by the cag pathogenicity island (PAI). The adhesins ascertain intimate bacterial contact to gastric epithelial cells, while the T4SS represents an extracellular pilus-like structure for the translocation of the effector protein CagA. Numerous T4SS components including CagI, CagL, CagY, and CagA have been shown to target the integrin-β₁ receptor followed by translocation of CagA across the host cell membrane. The interaction of CagA with membrane-anchored phosphatidylserine and CagA-containing outer membrane vesicles may also play a role in the delivery process. Translocated CagA undergoes tyrosine phosphorylation in C-terminal EPIYA-repeat motifs by oncogenic Src and Abl kinases. CagA then interacts with an array of host signaling proteins followed by their activation or inactivation in phosphorylation-dependent and phosphorylation-independent fashions. We now count about 25 host cell binding partners of intracellular CagA, which represent the highest quantity of all currently known virulence-associated effector proteins in the microbial world. Here we review the research progress in characterizing interactions of CagA with multiple host cell receptors in the gastric epithelium, including integrin-β₁, EGFR, c-Met, CD44, E-cadherin, and gp130. The contribution of these interactions to H. pylori colonization, signal transduction, and gastric pathogenesis is discussed.
Collapse
Affiliation(s)
- Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstr. 5, D-91058 Erlangen, Germany.
| | - Nicole Tegtmeyer
- Division of Microbiology, Department of Biology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstr. 5, D-91058 Erlangen, Germany.
| |
Collapse
|
24
|
Exploiting the Gastric Epithelial Barrier: Helicobacter pylori’s Attack on Tight and Adherens Junctions. Curr Top Microbiol Immunol 2017; 400:195-226. [DOI: 10.1007/978-3-319-50520-6_9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
25
|
Hashinaga M, Suzuki R, Akada J, Matsumoto T, Kido Y, Okimoto T, Kodama M, Murakami K, Yamaoka Y. Differences in amino acid frequency in CagA and VacA sequences of Helicobacter pylori distinguish gastric cancer from gastric MALT lymphoma. Gut Pathog 2016; 8:54. [PMID: 27833662 PMCID: PMC5101760 DOI: 10.1186/s13099-016-0137-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 10/26/2016] [Indexed: 12/20/2022] Open
Abstract
Background Helicobacter pylori is a pathogenic bacterium that causes various gastrointestinal diseases. The most common gastric malignancies associated with H. pylori are gastric cancer and lymphoma of mucosa associated lymphoid tissue (MALT). Helicobacter pylori virulence genes, namely cagA and vacA, are known to be associated with malignancy development. Conventionally, cagA and vacA were classified by looking at partial sequences of the genes. However, such genotyping has hardly proven useful predicting different risks for gastric cancer or MALT lymphoma. In search of new loci that distinguish these diseases, we investigated the full sequences of cagA and vacA. Results We compared cagA and vacA sequences of 18 and 12 H. pylori strains obtained, respectively, from patients with gastric cancer and MALT lymphoma in Oita, Japan. Conventional genotyping of cagA and vacA showed no significant difference between the two diseases. We further investigated the full protein sequences of CagA and VacA to identify loci where allele frequency was significantly different between the diseases. We found four such loci on CagA, and three such loci on VacA. We also inspected the corresponding loci on the genes of 22 gastritis strains that potentially lead to gastric cancer or MALT lymphoma in the long run. Significant differences were observed at one CagA locus between gastritis and MALT lymphoma strains, and at one VacA locus between gastritis and gastric cancer strains. Conclusions We found novel candidate loci in H. pylori virulence genes in association with two different types of gastric malignancies that could not be differentiated by conventional genotyping. Biological connotations of the amino acid polymorphisms merit further study. Electronic supplementary material The online version of this article (doi:10.1186/s13099-016-0137-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Masahiko Hashinaga
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan ; Department of Gastroenterology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Rumiko Suzuki
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Takashi Matsumoto
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Yasutoshi Kido
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Tadayoshi Okimoto
- Department of Gastroenterology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Masaaki Kodama
- Department of Gastroenterology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan ; Faculty of Welfare and Health Science, Oita University, 700 Dannoharu, Oita, Oita 870-1192 Japan
| | - Kazunari Murakami
- Department of Gastroenterology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593 Japan ; Department of Medicine-Gastroenterology, Baylor College of Medicine and Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX USA
| |
Collapse
|
26
|
Huang H, Svoboda RA, Lazenby AJ, Saowapa J, Chaika N, Ding K, Wheelock MJ, Johnson KR. Up-regulation of N-cadherin by Collagen I-activated Discoidin Domain Receptor 1 in Pancreatic Cancer Requires the Adaptor Molecule Shc1. J Biol Chem 2016; 291:23208-23223. [PMID: 27605668 DOI: 10.1074/jbc.m116.740605] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Indexed: 12/13/2022] Open
Abstract
Pancreatic ductal adenocarcinomas are highly malignant cancers characterized by extensive invasion into surrounding tissues, metastasis to distant organs, and a limited response to therapy. A main feature of pancreatic ductal adenocarcinomas is desmoplasia, which leads to extensive deposition of collagen I. We have demonstrated that collagen I can induce epithelial-mesenchymal transition (EMT) in pancreatic cancer cells. A hallmark of EMT is an increase in the expression of the mesenchymal cadherin N-cadherin. Previously we showed up-regulation of N-cadherin promotes tumor cell invasion and that collagen I-induced EMT is mediated by two collagen receptors, α2β1-integrin and discoidin domain receptor 1 (DDR1). DDR1 is a receptor-tyrosine kinase widely expressed during embryonic development and in many adult tissues and is also highly expressed in many different cancers. In the signaling pathway initiated by collagen, we have shown proline-rich tyrosine kinase 2 (Pyk2) is downstream of DDR1. In this study we found isoform b of DDR1 is responsible for collagen I-induced up-regulation of N-cadherin and tyrosine 513 of DDR1b is necessary. Knocking down Shc1, which binds to tyrosine 513 of DDR1b via its PTB (phosphotyrosine binding) domain, eliminates the up-regulation of N-cadherin. The signaling does not require a functional SH2 domain or the tyrosine residues commonly phosphorylated in Shc1 but is mediated by the interaction between a short segment of the central domain of Shc1 and the proline-rich region of Pyk2. Taken together, these data illustrate DDR1b, but not DDR1a, mediates collagen I-induced N-cadherin up-regulation, and Shc1 is involved in this process by coupling to both DDR1 and Pyk2.
Collapse
Affiliation(s)
- Huocong Huang
- From the Department of Biochemistry and Molecular Biology, College of Medicine
| | | | - Audrey J Lazenby
- Department of Pathology and Microbiology, College of Medicine, and
| | | | - Nina Chaika
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha Nebraska 68198
| | - Ke Ding
- State Key Laboratory of Respiratory Diseases, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, #190 Kaiyuan Avenue, Guangzhou 510530, China, and
| | - Margaret J Wheelock
- From the Department of Biochemistry and Molecular Biology, College of Medicine.,Department of Oral Biology, College of Dentistry.,Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha Nebraska 68198
| | - Keith R Johnson
- From the Department of Biochemistry and Molecular Biology, College of Medicine, .,Department of Oral Biology, College of Dentistry.,Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha Nebraska 68198.,Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198
| |
Collapse
|
27
|
Lind J, Backert S, Hoffmann R, Eichler J, Yamaoka Y, Perez-Perez GI, Torres J, Sticht H, Tegtmeyer N. Systematic analysis of phosphotyrosine antibodies recognizing single phosphorylated EPIYA-motifs in CagA of East Asian-type Helicobacter pylori strains. BMC Microbiol 2016; 16:201. [PMID: 27590005 PMCID: PMC5009636 DOI: 10.1186/s12866-016-0820-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 05/19/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Highly virulent strains of the gastric pathogen Helicobacter pylori encode a type IV secretion system (T4SS) that delivers the effector protein CagA into gastric epithelial cells. Translocated CagA undergoes tyrosine phosphorylation by members of the oncogenic c-Src and c-Abl host kinases at EPIYA-sequence motifs A, B and D in East Asian-type strains. These phosphorylated EPIYA-motifs serve as recognition sites for various SH2-domains containing human proteins, mediating interactions of CagA with host signaling factors to manipulate signal transduction pathways. Recognition of phospho-CagA is mainly based on the use of commercial pan-phosphotyrosine antibodies that were originally designed to detect phosphotyrosines in mammalian proteins. Specific anti-phospho-EPIYA antibodies for each of the three sites in CagA are not forthcoming. RESULTS This study was designed to systematically analyze the detection preferences of each phosphorylated East Asian CagA EPIYA-motif by pan-phosphotyrosine antibodies and to determine a minimal recognition sequence. We synthesized phospho- and non-phosphopeptides derived from each predominant EPIYA-site, and determined the recognition patterns by seven different pan-phosphotyrosine antibodies using Western blotting, and also investigated representative East Asian H. pylori isolates during infection. The results indicate that a total of only 9-11 amino acids containing the phosphorylated East Asian EPIYA-types are required and sufficient to detect the phosphopeptides with high specificity. However, the sequence recognition by the different antibodies was found to bear high variability. From the seven antibodies used, only four recognized all three phosphorylated EPIYA-motifs A, B and D similarly well. Two of the phosphotyrosine antibodies preferentially bound primarily to the phosphorylated motif A and D, while the seventh antibody failed to react with any of the phosphorylated EPIYA-motifs. Control experiments confirmed that none of the antibodies reacted with non-phospho-CagA peptides and in accordance were able to recognize phosphotyrosine proteins in human cells. CONCLUSIONS The results of this study disclose the various binding preferences of commercial anti-phosphotyrosine antibodies for phospho-EPIYA-motifs, and are valuable in the application for further characterization of CagA phosphorylation events during infection with H. pylori and risk prediction for gastric disease development.
Collapse
Affiliation(s)
- Judith Lind
- Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstr. 5, D-91058, Erlangen, Germany
| | - Steffen Backert
- Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstr. 5, D-91058, Erlangen, Germany
| | - Rebecca Hoffmann
- Department of Chemistry and Pharmacy, Friedrich Alexander University Erlangen-Nuremberg, Schuhstraße 19, D-91052, Erlangen, Germany
| | - Jutta Eichler
- Department of Chemistry and Pharmacy, Friedrich Alexander University Erlangen-Nuremberg, Schuhstraße 19, D-91052, Erlangen, Germany
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan
| | - Guillermo I Perez-Perez
- Department of Medicine and Microbiology, New York University, Langone Medical Centre, New York, USA
| | - Javier Torres
- Unidad de Investigación en Enfermedades Infecciosas, Hospital de Pediatría del Instituto Mexicano del Seguro Social, Mexico City, México
| | - Heinrich Sticht
- Bioinformatics, Institute for Biochemistry, Friedrich Alexander University Erlangen-Nuremberg, Fahrstrasse 17, D-91054, Erlangen, Germany
| | - Nicole Tegtmeyer
- Department of Biology, Division of Microbiology, Friedrich Alexander University Erlangen-Nuremberg, Staudtstr. 5, D-91058, Erlangen, Germany.
| |
Collapse
|
28
|
Tegtmeyer N, Moodley Y, Yamaoka Y, Pernitzsch SR, Schmidt V, Traverso FR, Schmidt TP, Rad R, Yeoh KG, Bow H, Torres J, Gerhard M, Schneider G, Wessler S, Backert S. Characterisation of worldwide Helicobacter pylori strains reveals genetic conservation and essentiality of serine protease HtrA. Mol Microbiol 2015; 99:925-44. [PMID: 26568477 PMCID: PMC4832355 DOI: 10.1111/mmi.13276] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2015] [Indexed: 12/11/2022]
Abstract
HtrA proteases and chaperones exhibit important roles in periplasmic protein quality control and stress responses. The genetic inactivation of htrA has been described for many bacterial pathogens. However, in some cases such as the gastric pathogen Helicobacter pylori, HtrA is secreted where it cleaves the tumour‐suppressor E‐cadherin interfering with gastric disease development, but the generation of htrA mutants is still lacking. Here, we show that the htrA gene locus is highly conserved in worldwide strains. HtrA presence was confirmed in 992 H. pylori isolates in gastric biopsy material from infected patients. Differential RNA‐sequencing (dRNA‐seq) indicated that htrA is encoded in an operon with two subsequent genes, HP1020 and HP1021. Genetic mutagenesis and complementation studies revealed that HP1020 and HP1021, but not htrA, can be mutated. In addition, we demonstrate that suppression of HtrA proteolytic activity with a newly developed inhibitor is sufficient to effectively kill H. pylori, but not other bacteria. We show that Helicobacter
htrA is an essential bifunctional gene with crucial intracellular and extracellular functions. Thus, we describe here the first microbe in which htrA is an indispensable gene, a situation unique in the bacterial kingdom. HtrA can therefore be considered a promising new target for anti‐bacterial therapy.
Collapse
Affiliation(s)
- Nicole Tegtmeyer
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058, Erlangen, Germany.,Institut für Medizinische Mikrobiologie, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, D-39120, Magdeburg, Germany
| | - Yoshan Moodley
- Department of Zoology, University of Venda, Private Bag X5050, Thohoyandou, 0950, South Africa.,Konrad-Lorenz-Institut für Vergleichende Verhaltensforschung, Department für Integrative Biologie und Evolution, Veterinärmedizinische Universität Wien, Savoyenstr. 1a, A-1160, Wien, Austria
| | - Yoshio Yamaoka
- Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Dept. Medicine-Gastroenterology, Houston, TX, USA.,Oita University Faculty of Medicine, Dept. Environmental and Preventive Medicine, Yufu, Japan
| | - Sandy Ramona Pernitzsch
- Research Center for Infectious Diseases (ZINF), University of Würzburg, Josef-Schneider-Str. 2/Bau D15, D-97080, Würzburg, Germany
| | - Vanessa Schmidt
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058, Erlangen, Germany
| | - Francisco Rivas Traverso
- Institut für Medizinische Mikrobiologie, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, D-39120, Magdeburg, Germany
| | - Thomas P Schmidt
- Department of Molecular Biology, Division of Microbiology, Paris-Lodron University of Salzburg, Billroth Str. 11, A-5020, Salzburg, Austria
| | - Roland Rad
- II Medical Department, Klinikum Rechts der Isar, Technical University Munich, Munich, Germany.,German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Khay Guan Yeoh
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ho Bow
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Javier Torres
- Unidad de Investigacion en Enfermedades Infecciosas, UMAE Pediatria, IMSS, Mexico City, Mexico
| | - Markus Gerhard
- Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, 81675, Germany
| | - Gisbert Schneider
- ETH Zürich, Institut für Pharmazeutische Wissenschaften, Vladimir-Prelog-Weg 4, CH-8093, Zürich, Switzerland
| | - Silja Wessler
- Department of Molecular Biology, Division of Microbiology, Paris-Lodron University of Salzburg, Billroth Str. 11, A-5020, Salzburg, Austria
| | - Steffen Backert
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058, Erlangen, Germany.,Institut für Medizinische Mikrobiologie, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, D-39120, Magdeburg, Germany
| |
Collapse
|
29
|
A specific A/T polymorphism in Western tyrosine phosphorylation B-motifs regulates Helicobacter pylori CagA epithelial cell interactions. PLoS Pathog 2015; 11:e1004621. [PMID: 25646814 PMCID: PMC4412286 DOI: 10.1371/journal.ppat.1004621] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 12/16/2014] [Indexed: 12/15/2022] Open
Abstract
Helicobacter pylori persistently colonizes the human stomach, with mixed roles in human health. The CagA protein, a key host-interaction factor, is translocated by a type IV secretion system into host epithelial cells, where its EPIYA tyrosine phosphorylation motifs (TPMs) are recognized by host cell kinases, leading to multiple host cell signaling cascades. The CagA TPMs have been described as type A, B, C or D, each with a specific conserved amino acid sequence surrounding EPIYA. Database searching revealed strong non-random distribution of the B-motifs (including EPIYA and EPIYT) in Western H. pylori isolates. In silico analysis of Western H. pylori CagA sequences provided evidence that the EPIYT B-TPMs are significantly less associated with gastric cancer than the EPIYA B-TPMs. By generating and using a phosphorylated CagA B-TPM-specific antibody, we demonstrated the phosphorylated state of the CagA B-TPM EPIYT during H. pylori co-culture with host cells. We also showed that within host cells, CagA interaction with phosphoinositol 3-kinase (PI3-kinase) was B-TPM tyrosine-phosphorylation-dependent, and the recombinant CagA with EPIYT B-TPM had higher affinity to PI3-kinase and enhanced induction of AKT than the isogenic CagA with EPIYA B-TPM. Structural modeling of the CagA B-TPM motif bound to PI3-kinase indicated that the threonine residue at the pY+1 position forms a side-chain hydrogen bond to N-417 of PI3-kinase, which cannot be formed by alanine. During co-culture with AGS cells, an H. pylori strain with a CagA EPIYT B-TPM had significantly attenuated induction of interleukin-8 and hummingbird phenotype, compared to the isogenic strain with B-TPM EPIYA. These results suggest that the A/T polymorphisms could regulate CagA activity through interfering with host signaling pathways related to carcinogenesis, thus influencing cancer risk.
Collapse
|
30
|
Tenguria S, Ansari SA, Khan N, Ranjan A, Devi S, Tegtmeyer N, Lind J, Backert S, Ahmed N. Helicobacter pylori cell translocating kinase (CtkA/JHP0940) is pro-apoptotic in mouse macrophages and acts as auto-phosphorylating tyrosine kinase. Int J Med Microbiol 2014; 304:1066-76. [PMID: 25172221 DOI: 10.1016/j.ijmm.2014.07.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 06/26/2014] [Accepted: 07/28/2014] [Indexed: 12/16/2022] Open
Abstract
The Helicobacter pylori gene JHP0940 has been shown to encode a serine/threonine kinase which can induce cytokines in gastric epithelial cells relevant to chronic gastric inflammation. Here we demonstrate that JHP0940 can be secreted by the bacteria, triggers apoptosis in cultured mouse macrophages and acts as an auto-phosphorylating tyrosine kinase. Recombinant JHP0940 protein was found to decrease the viability of RAW264.7 cells (a mouse macrophage cell line) up to 55% within 24h of co-incubation. The decreased cellular viability was due to apoptosis, which was confirmed by TUNEL assay and Fas expression analysis by flow-cytometry. Further, we found that caspase-1 and IL-1beta were activated upon treatment with JHP0940. These results point towards possible action through the host inflammasome. Our in vitro studies using tyrosine kinase assays further demonstrated that JHP0940 acts as auto-phosphorylating tyrosine kinase and induces pro-inflammatory cytokines in RAW264.7 cells. Upon exposure with JHP0940, these cells secreted IL-1beta, TNF-alpha and IL-6, in a dose- and time-dependent manner, as detected by ELISA and transcript profiling by q-RT-PCR. The pro-inflammatory, pro-apoptotic and other regulatory responses triggered by JHP0940 lead to the assumption of its possible role in inducing chronic inflammation for enhanced bacterial persistence and escape from host innate immune responses by apoptosis of macrophages.
Collapse
Affiliation(s)
- Shivendra Tenguria
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500046, India
| | - Suhail A Ansari
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500046, India
| | - Nooruddin Khan
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500046, India
| | - Amit Ranjan
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500046, India
| | - Savita Devi
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500046, India
| | - Nicole Tegtmeyer
- Division of Microbiology, Department of Biology, Friedrich Alexander University Nuremberg, D-91058 Erlangen, Germany
| | - Judith Lind
- Division of Microbiology, Department of Biology, Friedrich Alexander University Nuremberg, D-91058 Erlangen, Germany
| | - Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich Alexander University Nuremberg, D-91058 Erlangen, Germany
| | - Niyaz Ahmed
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500046, India.
| |
Collapse
|