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El-Khlousy M, Rahman EA, Mostafa S, Bassam A, Elgawad HA, Elnasr MS, Mohey M, Ghaith D. Study of the clinical relevance of Helicobacter pylori virulence genes to gastric diseases among Egyptian patients. Arab J Gastroenterol 2016; 17:90-4. [PMID: 27344093 DOI: 10.1016/j.ajg.2016.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/24/2016] [Indexed: 01/22/2023]
Abstract
BACKGROUND AND STUDY AIMS Helicobacter pylori infection is common in Egypt. It has been associated with gastritis, ulcers and it is a risk factor for gastric cancer. We aimed to study the correlation between the presence of H. pylori virulence factors and the histopathological and endoscopic findings in gastric biopsies. PATIENTS AND METHODS Gastric biopsies from thirty seven patients scheduled for diagnostic endoscopy in Cairo University hospital were included in the study. All gastric biopsies were subjected to histopathological examination and PCR assay for detection of 16S rRNA gene to diagnose H. pylori infection, detection of H. pylori virulence factors by PCR for cagA and vacA genotypes and serological analysis of H. pylori (cagA, vacA, P25, and P19) IgG antibodies by immunoblot assay were done. RESULTS H. pylori infection was detected in 23 (62.2%) cases by histopathology while 28/37 (75.7%) were positive for H. pylori 16S rRNA gene by PCR. By PCR seventeen samples out of 37 (45.9%) were positive for cagA gene and five (13.5%) for cag empty site gene. CONCLUSION The most common vacA genotype identified was vacA s2m2 genotype in 10 (27.02%). No statistical correlation was found between IgG antibodies against different antigens of H. pylori virulence factors (cagA, vacA, p25, and p19) and the degree of gastritis except for IgG antibodies against the UreA antigen.
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Affiliation(s)
- Mona El-Khlousy
- Clinical and Chemical Pathology Department, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
| | - Eiman A Rahman
- Clinical and Chemical Pathology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Sally Mostafa
- Clinical and Chemical Pathology Department, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
| | - Amira Bassam
- Pathology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Heba A Elgawad
- Clinical and Chemical Pathology Department, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
| | - Mohamed S Elnasr
- Endemic Medicine and Hepatology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Mohammad Mohey
- Endemic Medicine and Hepatology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Doaa Ghaith
- Clinical and Chemical Pathology Department, Faculty of Medicine, Cairo University, Cairo, Egypt.
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Hilton GM, Hoppin JA. Is Helicobacter Pylori an endogenous source of diethyl phthalate in humans? ENVIRONMENTAL RESEARCH 2014; 134:402-404. [PMID: 25218706 PMCID: PMC5017147 DOI: 10.1016/j.envres.2014.08.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 07/28/2014] [Accepted: 08/19/2014] [Indexed: 06/03/2023]
Abstract
Monoethyl phthalate (MEP) is a metabolite used to assess exposure to diethyl phthalate (DEP). Helicobacter Pylori (HP) has been shown to produce DEP in laboratory studies. We used NHANES 1999-2000 data for 1623 adults to investigate whether HP seropositivity was associated with MEP levels. MEP levels were higher in individuals with HP seropositivity (p=0.0237), however the association differed by race. These results suggest that HP may be an endogenous source of DEP in some populations.
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Affiliation(s)
- Gina M Hilton
- Department of Biological Sciences, North Carolina State University, CB 7633, Raleigh, NC 27695, United States
| | - Jane A Hoppin
- Department of Biological Sciences, North Carolina State University, CB 7633, Raleigh, NC 27695, United States.
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Aziz F, Sherwani SK, Akhtar SS, Kazmi SU. Development of an in-house enzyme-linked immunosorbent assay based on surface whole cell antigen for diagnosis of Helicobacter pylori infection in patients with gastroduodenal ulcer disease. World J Microbiol Biotechnol 2013; 30:305-15. [PMID: 23921679 DOI: 10.1007/s11274-013-1448-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 07/25/2013] [Indexed: 01/01/2023]
Abstract
Helicobacter pylori (H. pylori) is a causative agent of gastritis, gastroduodenal ulcers and gastric adenocarcinoma. More than 50% world population is colonized by H. pylori, which is closely related to the chronic gastritis and gastric ulcer infection. In this study, a total of 214 gastritis patient's serum samples were screened for anti-H. pylori IgG antibody. A 96-well plate coated with 20 μg/ml antigen and hundred-fold diluted patient's serum was allowed to react. After extensive washing with buffer, 1:2,500 diluted conjugated secondary antibody was added. Later substrate was added to observe positivity by measuring the intensity of color. Statistical analyses were performed, and p value of <0.01 was taken as significant; 84% male patients and 89% female patients, respectively, tested positive for H. pylori, while agewise distribution was 35-45 years males (40%) and 35-55 years females (52%) were found highest number of H. pylori infected patients. In-house ELISA based on surface whole cell antigen (wELISA) showed a sensitivity of 93%, specificity of 100%, accuracy 94% and κ value 0.86 with significant correlation R-0.77020; p < 0.0001. We conclude that H. pylori local isolates surface antigen was satisfactory for diagnosis as different parameters were adjusted according to the local H. pylori isolates. Fluctuations in serum antibody titer predict the variation in an individual's response of the host against H. pylori. In-house wELISA could provide a reliable and a clinically useful method for the diagnosis of H. pylori infection in patients of Karachi, Pakistan.
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Affiliation(s)
- Faisal Aziz
- Immunology and Infectious Diseases Research Laboratory (IIDRL), Department of Microbiology, University of Karachi, Karachi, 75270, Pakistan,
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Chomvarin C, Ottiwet O, Hahnvajanawong C, Intapan PM, Wongwajana S. Seroreactivity to specific antigens of Helicobacter pylori infection is associated with an increased risk of the dyspeptic gastrointestinal diseases. Int J Infect Dis 2009; 13:647-54. [DOI: 10.1016/j.ijid.2008.12.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 12/18/2008] [Accepted: 12/18/2008] [Indexed: 01/06/2023] Open
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Xue LJ, Su QS, Yang JH, Lin Y. Autoimmune responses induced by Helicobacter pylori improve the prognosis of gastric carcinoma. Med Hypotheses 2008; 70:273-6. [PMID: 17681432 DOI: 10.1016/j.mehy.2007.05.045] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2007] [Accepted: 05/29/2007] [Indexed: 12/17/2022]
Abstract
Gastric carcinoma (GC) remains one of most serious malignant tumors worldwide, with Helicobacter pylori being the definite carcinogen. The H. pylori components, cytotoxin-associated gene A (CagA), vacuolating toxin A (VacA) and blood-group antigen-binding adhesin gene (BabA), can mimic and bind to specific receptors or surface molecules both on gastric epithelial cells and platelets, in which CagA and VacA may also be directly involved in loosening of tight junctions in monolayers of polarized gastric epithelial cells. It has been shown that a history of H. pylori infection is found in the majority of patients with GC, and that anti-CagA, anti-VacA and anti-BabA antibodies targeting both H. pylori components and host mimic molecules can be detected in them with increased levels. Patients with GC who are positive for H. pylori prospectively have a better outlook than those negative. The stimulation of mentioned autoantibodies in antigen processing and presentation and subsequent T-cell activation and proliferation improves host immune status. On the other hand, in an autoimmune response, autoantibodies can induce the cross-reaction against those localized or circulating GC cells, which are characterized by mimic or absorbed H. pylori antigens, and lead to the killing and even suppressing of metastasis of cancer cells. Therefore, we here hypothesize that autoimmune responses induced by H. pylori components may play a key role in improving the prognosis of patients with gastric carcinoma.
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Affiliation(s)
- Li-Jun Xue
- Department of Oncology, Jinling Hospital, 210002 Nanjing, PR China
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6
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Simán JH, Engstrand L, Berglund G, Forsgren A, Florén CH. Helicobacter pylori and CagA seropositivity and its association with gastric and oesophageal carcinoma. Scand J Gastroenterol 2007; 42:933-40. [PMID: 17613922 DOI: 10.1080/00365520601173863] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Helicobacter pylori infection is an established risk factor for non-cardia gastric adenocarcinoma. Infection with H. pylori strains harbouring the cagA pathology island may augment this association. H. pylori infection may at the same time reduce the risk for oesophageal carcinoma. However, prospective data on the association between CagA seropositivity and gastric or oesophageal carcinomas are limited. The purpose of this study was to investigate whether CagA seropositivity among H. pylori seropositive subjects is associated with gastric or oesophageal carcinomas. MATERIAL AND METHODS A nested case-control study was performed in the Malmö Preventive Medicine cohort consisting of 32,906 middle-aged subjects. Tumour cases were identified by the Swedish National Cancer Registry. The Western blot method Helicoblot 2.1 was used to detect H. pylori and CagA seropositivity. RESULTS Non-cardia gastric adenocarcinoma was associated with H. pylori seropositivity, odds ratio 17.8 (95% CI: 4.2-74.8; 67 cases). The odds ratio for CagA seropositivity among H. pylori seropositive subjects was 9.7 (95% CI: 1.5-infinity). No significant associations were found between cardia gastric adenocarcinoma and H. pylori or CagA seropositivity among H. pylori seropositive subjects; odds ratios were 1.5 (95% CI: 0.51-4.8) and 2.7 (95% CI: 0.38-infinity), respectively (24 cases). Oesophageal adenocarcinoma and oesophageal squamous cell carcinoma were not significantly associated with H. pylori seropositivity or with CagA seropositivity among H. pylori seropositive subjects; the odds ratios associated with oesophageal adenocarcinoma were 0.46 (95% CI: 0.07-2.6) and 0.38 (95% CI: 0.02-24), respectively. Corresponding odds ratios for oesophageal squamous cell carcinoma were 0.44 (95% CI: 0.15-1.2; 37 cases) and 2.0 (95% CI: 0.24-infinity), respectively. CONCLUSIONS CagA seropositivity among H. pylori seropositive subjects is a risk factor for non-cardia gastric adenocarcinoma.
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Affiliation(s)
- J Henrik Simán
- Department of Medicine, Malmö University Hospital, Lund University, Malmö, Sweden.
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Yang KC, Chu A, Liao CS, Lin YM, Wang GM. Evaluation of the role of H pylori infection in pathogenesis of gastric cancer by immunoblot assay. World J Gastroenterol 2006; 12:7029-32. [PMID: 17109500 PMCID: PMC4087349 DOI: 10.3748/wjg.v12.i43.7029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To elucidate the different serological reactions to H pylori using the immunoblotting technique for further understanding of its pathogenic role in gastric cancer.
METHODS: A total of 54 patients were divided into two groups after upper gastrointestinal endoscopy: normal control group (25 patients) and gastric cancer group (29 patients). Both groups were further divided into H pylori (+) and H pylori (-) subgroups based on the results of CLO test, Giemsa staining and culture. Sera were further analyzed with the immunoblotting technique (HelicoBlot 2.0, Genelabs Diagnostics, Singapore).
RESULTS: The positive rate of the immunoblotting test was as high as 88.9% in the H pylori (-) gastric cancer group and only 14.3% in the H pylori (-) normal control group with a statistically significant difference.
CONCLUSION: The prevalence of H pylori infection is higher in gastric cancer patients than in the normal controls, suggesting that H pylori may play a role in the pathogenesis of gastric cancer.
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Affiliation(s)
- Kuo-Ching Yang
- Division of Gastroenterology, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, China
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8
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Abasiyanik MF, Tunc M, Salih BA. Enzyme immunoassay and immunoblotting analysis of Helicobacter pylori infection in Turkish asymptomatic subjects. Diagn Microbiol Infect Dis 2005; 50:173-7. [PMID: 15541602 DOI: 10.1016/j.diagmicrobio.2004.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Approximately half of the world population is infected with Helicobacter pylori, particularly in developing countries. The aims of the study were to detect H. pylori infection in asymptomatic Turkish subjects, correlate the infection with the associated risk factors, and to evaluate the cytotoxin-associated gene (CagA) status and other H. pylori antigens. Three hundred nine asymptomatic subjects (124 female) 1-82 years of age (average: 31 years) were serologically tested by enzyme immunoassay and immunoblotting. The enzyme immunoassay detected IgG anti-H. pylori antibodies in sera of 216 (70%) out of 309 subjects, 132 (61%) male. Infection rates of 42% in subjects <10 years of age, 55% in 10-19 years, 66% in 20-29 years, 78% in 30-39 years, 79% in 40-49 years, 91% in 50-59 years, 100% in 60-69 years, and 80% in those >70 years of age were detected. Subjects >45 years of age had significantly higher antibody responses, odds ratio = 0.16 (95% confidence interval: 0.07-0.37), than those <45 years. H. pylori infection was significantly higher in married subjects, odds ratio = 0.38 (95% confidence interval: 0.20-0.73), and those with low socioeconomic status. No correlation between gender, education, smoking, and nonsteroidal anti-inflammatory drug intake and infection was detected. Immunoblots revealed antibodies to CagA in 58 (83%) of 70 samples tested. H. pylori infection is prevalent in the asymptomatic Turkish subjects. Marital and socioeconomic status was significantly associated with the acquisition of H. pylori. Antibodies to CagA antigen were highly prevalent in these subjects.
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Affiliation(s)
- M Fatih Abasiyanik
- Department of Biology/Microbiology Unit, B. cekmece, Fatih University, Istanbul, Turkey
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Tanabe S, Hinode D, Yokoyama M, Fukui M, Nakamura R, Yoshioka M, Grenier D, Mayrand D. Helicobacter pylori and Campylobacter rectus share a common antigen. ORAL MICROBIOLOGY AND IMMUNOLOGY 2003; 18:79-87. [PMID: 12654095 DOI: 10.1034/j.1399-302x.2003.00049.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIM The aim of this study was to investigate the presence of antigens with immunological cross-reactivity in periodontopathogenic bacteria and Helicobacter pylori, the pathogen associated with gastritis and peptic ulcers in human. MATERIALS AND METHODS/RESULTS Among the putative periodontopathogens tested (Actinobacillus actinomycetemcomitans, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia and Treponema denticola), cross-reactive bands were only detected in C. rectus by SDS-PAGE/Western immunoblotting analysis using a polyclonal antibody directed to H. pylori cells. One of these cross-reactive antigens, a 64-kDa band antigen, also reacted with a monoclonal antibody directed to the human heat shock protein (HSP) 60. The N-terminal amino acid sequence of this C. rectus protein revealed a high degree of homology with corresponding regions of other HSPs belonging to the HSP60 family, indicating that the 64-kDa antigen was a GroEL protein. The nucleotide sequence of the C. rectus GroEL protein coded for a 547 amino acid protein with a predicted size of 57.8 kDa. Comparison of the alignment of the deduced amino acid sequence of the GroEL protein of C. rectus with that of H. pylori showed a high degree of similarity throughout its length (76.8%). GroEL protein from C. rectus possessed the ability to stimulate production of IL-6 by a confluent monolayer of human gingival epithelial cells and was cytotoxic when used at a high concentration. CONCLUSIONS This study reveals an immunological relationship between H. pylori and C. rectus, and clearly indicates that one of the shared antigens is a GroEL protein possessing a biological activity that might play a role in the initiation and progression of periodontal disease.
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Affiliation(s)
- S Tanabe
- Department of Preventive Dentistry, School of Dentistry, The University of Tokushima, Tokushima City, Japan
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Evans DJ, Evans DG. Helicobacter pylori CagA: analysis of sequence diversity in relation to phosphorylation motifs and implications for the role of CagA as a virulence factor. Helicobacter 2001; 6:187-98. [PMID: 11683921 DOI: 10.1046/j.1523-5378.2001.00028.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
CagA is transported into host target cells and subsequently phosphorylated. Clearly this is a mechanism by which Helicobacter pylori could take control of one or more host cell signal transduction pathways. Presumably the end result of this interaction favors survival of H. pylori, irrespective of eventual damage to the host cell. CagA is noted for its amino acid (AA) sequence diversity, both within and outside the variable region of the molecule. The primary purpose of this review is to examine how variation in the type and number of CagA phosphorylation sites might determine the outcome of infection by different strains of H. pylori. The answer to this question could help to explain the widely disparate results obtained when H. pylori CagA status has been compared to type and severity of disease outcome in different populations, that is in different countries. Analysis of all available CagA sequences revealed that CagA contains both tyrosine phosphorylation motifs (TPMs) and cyclic-AMP-dependent phosphorylation motifs (CPMs). There are two potential CPMs near the N-terminus of CagA and at least two in the repeat region; these are not all equally well conserved. We also defined a 48-residue AA sequence, which includes the N-terminal TPM at tyrosine (Y)-122, which distinguishes between Eastern (Hong Kong-Taiwan-Japan-Thailand) H. pylori isolates and those from the West (Europe-Africa-the Americas-Australia). All 28 of the Eastern type CagA proteins have a functional N-terminal TPM whereas 11 of 47 (23.4%) of the Western type contain an inactive motif, with threonine (T) replacing the critical aspartic acid (D) residue. Only 13 of 24 (54%) known CagA sequences have an active TPM in the repeat region and only one has two TPMs in this region. The potential TPM near the C-terminus of CagA is not likely to be important since only 3 of 24 (12.5%) sequences were found to be intact. Protein database searches revealed that the AA sequence immediately following the TPM at Y-122 in CagA is homologous with a pair of PDZ domains which are common in signal transducing proteins, particularly tyrosine phosphatases. This provides a theoretical link between CagA and many of the observed responses of host cells to H. pylori. In summary, not all CagA proteins are equal in their potential for initiating host cell responses via signal transduction pathways. The degree of functional diversity of this protein depends upon which phosphorylation motifs are critical to the biological activity of CagA.
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Affiliation(s)
- D J Evans
- Department of Medicine, VA Medical Center and Baylor College of Medicine, Houston, Texas 77030, USA
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Figueiredo C, Quint W, Nouhan N, van den Munckhof H, Herbrink P, Scherpenisse J, de Boer W, Schneeberger P, Perez-Perez G, Blaser MJ, van Doorn LJ. Assessment of Helicobacter pylori vacA and cagA genotypes and host serological response. J Clin Microbiol 2001; 39:1339-44. [PMID: 11283053 PMCID: PMC87936 DOI: 10.1128/jcm.39.4.1339-1344.2001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori strains can be distinguished by genotyping of virulence-associated genes, such as vacA and cagA. Because serological discrimination between strain types would reduce the need for endoscopy, 61 patients carrying H. pylori were studied by vacA and cagA genotyping of H. pylori in gastric biopsy specimens and by detection of specific serum antibodies. Serological responses to H. pylori were determined by Helicoblot (versions 2.0 and 2.1). Antibodies to CagA also were determined by a rapid anti-CagA assay (Pyloriset screen CagA) as well as by two noncommercially developed enzyme immunoassays, each using a recombinant CagA protein. Assessment of performance of the Helicoblot assays indicated substantial interobserver variation, with kappa values between 0.20 and 0.93. There was no relationship between the serological profiles on the Helicoblot and the genotypes from the same patients, except for strong associations between the presence of anti-CagA and the cagA-positive and vacA s1 H. pylori genotypes. Detection of anti-CagA by the five different assays varied considerably, with kappa values ranging from 0.21 to 0.78. Using the cagA genotype as the "gold standard," the sensitivity and specificity of the anti-CagA assays varied from 71.4 to 85.7% and from 54.2 to 100%, respectively. Thus, serological profiles of antibodies to H. pylori are heterogeneous and, with the exception of anti-CagA antibodies, show no relation to the H. pylori vacA and cagA genotypes. Detection of anti-CagA antibodies is strongly dependent on the test used.
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Affiliation(s)
- C Figueiredo
- Delft Diagnostic Laboratory, Delft, The Netherlands
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Nessa J, Chart H, Owen RJ, Drasar B. Human serum antibody response to Helicobacter pylori whole cell antigen in an institutionalized Bangladeshi population. J Appl Microbiol 2001; 90:68-72. [PMID: 11155124 DOI: 10.1046/j.1365-2672.2001.01216.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To use a commercial ELISA kit and an immunoblot assay to investigate the antibody levels of selected members of the Bangladeshi population to Helicobacter pylori protein antigens. METHODS AND RESULTS Using immunoblotting, high seroprevalence rates were observed in all age groups, although the subjects within the 1-9 years age group had the highest seroprevalence of antibodies to H. pylori antigens. By ELISA, the highest level of seroprevalence was observed in those over the age of 20 years. CONCLUSION On the basis of these results the overall prevalence rate of H. pylori infection for the whole population was 77.4%; 77.9% for orphan boys and 76% for carers. CagA antibodies were detected in 86% of those with high levels of antibodies to H. pylori antigens. SIGNIFICANCE AND IMPACT OF THE STUDY A combination of immunoblotting and ELISA was the most efficient means of detecting serum antibodies to H. pylori antigens and could be applied to the screening of human sera for H. pylori-specific antibodies.
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Affiliation(s)
- J Nessa
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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