scholarly journals Helicobacter pylori Heat Shock Protein A: Serologic Responses and Genetic Diversity

1999 ◽  
Vol 6 (3) ◽  
pp. 377-382 ◽  
Author(s):  
Enders K. W. Ng ◽  
Stuart A. Thompson ◽  
Guillermo I. Pérez-Pérez ◽  
Imad Kansau ◽  
Arie van der Ende ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Helicobacter Pylori ◽  
Amino Acid ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Sequence Variation ◽  
Protein A ◽  
Nucleotide Sequences ◽  
Serological Response ◽  
H Pylori

ABSTRACT Helicobacter pylori synthesizes an unusual GroES homolog, heat shock protein A (HspA). The present study was aimed at an assessment of the serological response to HspA in a group of Chinese patients with defined gastroduodenal pathologies and determination of whether diversity is present in the nucleotide sequences encoding HspA in isolates from these patients. Serum samples collected from 154 patients who had an upper gastrointestinal pathology and the presence of H. pylori defined by biopsy were tested for an immunoglobulin G (IgG) serologic response to H. pylori HspA by an enzyme linked immunosorbant assay. HspA-encoding nucleotide sequences in H. pylori isolates from 14 patients (7 seropositive and 7 seronegative for HspA) were analyzed by PCR and direct sequencing of the PCR products. The sequencing results were compared to those of 48 isolates from other parts of the world. Of the 154 known H. pylori-positive patients, 54 (35.1%) were seropositive for HspA. The A domain (GroES homology) of HspA was highly conserved in the 14 isolates tested. Although the B domain (metal-binding site unique to H. pylori) resembled that in the known major variant, particular amino acid substitutions allowed definition of an HspA variant associated with isolates from East Asia. There were no associations between patient characteristics and HspA seropositivity or amino acid sequences. We confirmed in this study that the clinical outcomes of H. pylori infection are not related to HspA antigenicity or to sequence variation. However, B-domain sequence variation may be a marker for the study of the genetic diversity of H. pylori strains of different geographic origins.

scholarly journals Effects ofHelicobacter pyloriand Heat Shock Protein 70 on the Proliferation of Human Gastric Epithelial Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Liping Tao ◽  
Hai Zou ◽  
Zhimin Huang
Keyword(s):  
Helicobacter Pylori ◽  
Heat Shock ◽  
Epithelial Cells ◽  
Heat Shock Protein ◽  
Mtt Assay ◽  
Heat Shock Protein 70 ◽  
Hsp70 Expression ◽  
Gastric Epithelial Cells ◽  
Ags Cells ◽  
H Pylori

Infection ofHelicobacter pylori (H. pylori)changed the proliferation of gastric epithelial cells and decreased the expression of heat shock protein 70 (HSP70). However, the effects ofH. pylorion the proliferation of gastric epithelial cells and the roles of HSP70 during the progress need further investigation.Objective.To investigate the effects ofHelicobacter pylori (H. pylori)and heat shock protein 70 (HSP70) on the proliferation of human gastric epithelial cells.Methods. H. pyloriand a human gastric epithelial cell line (AGS) were cocultured. The proliferation of AGS cells was quantitated by an MTT assay, and the expression of HSP70 in AGS cells was detected by Western blotting. HSP70 expression in AGS cells was silenced by small interfering RNA (siRNA) to investigate the role of HSP70. ThesiRNA-treated AGS cells were cocultured withH. pyloriand cell proliferation was measured by an MTT assay.Results.The proliferation of AGS cells was accelerated by coculturing withH. pylorifor 4 and 8 h, but was suppressed at 24 and 48 h. HSP70 expression was decreased in AGS cells infected byH. pylorifor 48 h. The proliferation in HSP70-silenced AGS cells was inhibited after coculturing withH. pylorifor 24 and 48 h compared with the control group.Conclusions.Coculture ofH. pylorialtered the proliferation of gastric epithelial cells and decreased HSP70 expression. HSP70 knockdown supplemented the inhibitory effect ofH. pylorion proliferation of epithelial cells. These results indicate that the effects ofH. pylorion the proliferation of gastric epithelial cells at least partially depend on the decreased expression of HSP70 induced by the bacterium.

scholarly journals Identification of B-Cell Epitopes of HspA from Helicobacter pylori and Detection of Epitope Antibody Profiles in Naturally Infected Persons

Vaccines ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 65
Author(s):  
Xin Zhang ◽  
Shuli Sang ◽  
Qing Guan ◽  
Haoxia Tao ◽  
Yanchun Wang ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Heat Shock ◽  
B Cell ◽  
Protein A ◽  
Peptide Fragments ◽  
Nickel Ion ◽  
B Cell Epitopes ◽  
E Coli ◽  
Important Target ◽  
H Pylori

Helicobacter pylori (H. pylori), heat-shock protein A (HspA), is a bacterial heat-shock chaperone that serves as a nickel ion scavenging protein. Ni2+ is an important co-factor required for the maturation and enzymatic activity of H. pylori urease and [NiFe] hydrogenase, both of which are key virulence factors for pathogen survival and colonization. HspA is an important target molecule for the diagnosis, treatment, and immune prevention of H. pylori. In this work, HspA was truncated into five fragments to determine the location of an antigen immunodominant peptide. A series of overlapping, truncated 11-amino-acid peptides in immunodominant peptide fragments were synthesized chemically and screened by ELISA. The immunogenicity and antigenicity of the screened epitope peptides were verified by ELISA, Western blot, and lymphocyte proliferation tests. Two novel B-cell epitopes were identified, covering amino acids 2–31 of HspA, which are HP11 (2–12; KFQPLGERVLV) and HP19 (18–28; ENKTSSGIIIP). The antiserum obtained from HP11-KLH and HP19-KLH immunized mice can bind to naive HspA in H. pylori SS2000, rHspA expressed in E. coli, and the corresponding GST fusion peptide. Among HspA seropositive persons, the seropositive rates of HP11 and HP19 were 21.4% and 33.3%, respectively. Both of the B-cell epitopes of HspA are highly conserved epitopes with good antigenicity and immunogenicity.

scholarly journals Immunization with Heat Shock Protein A and γ-Glutamyl Transpeptidase Induces Reduction on the Helicobacter pylori Colonization in Mice

PLoS ONE ◽  
2015 ◽  
Vol 10 (6) ◽  
pp. e0130391 ◽  
Author(s):  
Xiaoli Zhang ◽  
Jinyong Zhang ◽  
Feng Yang ◽  
Weiru Wu ◽  
Heqiang Sun ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Protein A ◽  
Glutamyl Transpeptidase

scholarly journals Functional Properties of Helicobacter pylori VacA Toxin m1 and m2 Variants

2020 ◽  
Vol 88 (6) ◽  
Author(s):  
Rhonda R. Caston ◽  
Johanna C. Sierra ◽  
Nora J. Foegeding ◽  
Mandy D. Truelock ◽  
Anne M. Campbell ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Sequence Variation ◽  
Protein A ◽  
Chimeric Protein ◽  
Chimeric Proteins ◽  
Apical Surface ◽  
Terminal Portion ◽  
Content Type ◽  
Gastric Cells ◽  
H Pylori

ABSTRACT Helicobacter pylori colonizes the gastric mucosa and secretes a pore-forming toxin (VacA). Two main types of VacA, m1 and m2, can be distinguished by phylogenetic analysis. Type m1 forms of VacA have been extensively studied, but there has been relatively little study of m2 forms. In this study, we generated H. pylori strains producing chimeric proteins in which VacA m1 segments of a parental strain were replaced by corresponding m2 sequences. In comparison to the parental m1 VacA protein, a chimeric protein (designated m2/m1) containing m2 sequences in the N-terminal portion of the m region was less potent in causing vacuolation of HeLa cells, AGS gastric cells, and AZ-521 duodenal cells and had reduced capacity to cause membrane depolarization or death of AZ-521 cells. Consistent with the observed differences in activity, the chimeric m2/m1 VacA protein bound to cells at reduced levels compared to the binding levels of the parental m1 protein. The presence of two strain-specific insertions or deletions within or adjacent to the m region did not influence toxin activity. Experiments with human gastric organoids grown as monolayers indicated that m1 and m2/m1 forms of VacA had similar cell-vacuolating activities. Interestingly, both forms of VacA bound preferentially to the basolateral surface of organoid monolayers and caused increased cell vacuolation when interacting with the basolateral surface compared to the apical surface. These data provide insights into functional correlates of sequence variation in the VacA midregion (m region).

scholarly journals Cloning, expression and antigenic analysis of heat shock protein A gene of human Helicobacter pylori

2003 ◽  
Vol 11 (10) ◽  
pp. 1480-1484
Author(s):  
Zheng Jiang ◽  
Dan Pu ◽  
Ai-Long Huang ◽  
Xiao-Hong Tao ◽  
Pi-Long Wang
Keyword(s):  
Helicobacter Pylori ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Protein A ◽  
Antigenic Analysis

scholarly journals Helicobacter pylori heat-shock protein 60 induces interleukin-8 via a Toll-like receptor (TLR)2 and mitogen-activated protein (MAP) kinase pathway in human monocytes

2007 ◽  
Vol 56 (2) ◽  
pp. 154-164 ◽  
Author(s):  
Ying Zhao ◽  
Kenji Yokota ◽  
Kiyoshi Ayada ◽  
Yumiko Yamamoto ◽  
Tomayuki Okada ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
P38 Mapk ◽  
Heat Shock Protein 60 ◽  
Human Monocytes ◽  
Toll Like Receptor ◽  
Mapk Signalling ◽  
Mitogen Activated Protein ◽  
H Pylori

Previous reports have indicated that Helicobacter pylori heat-shock protein 60 (H. pylori-HSP60), as an immunodominant antigen, induces interleukin (IL)-8 production in human monocytes. The exact mechanism by which H. pylori-HSP60 induces IL-8 production in monocytes has not been fully elucidated. In the present study, the downstream pathway by which H. pylori-HSP60 induces IL-8 secretion in human monocytic cell lines was investigated. Intact H. pylori, heat-killed H. pylori and H. pylori recombinant HSP60 (rHpHSP60) all induced the secretion of IL-8 and the activation of mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) and p38, but not c-Jun N-terminal kinase (JNK), up to 24 h in NOMO1 cells. The specific inhibitors PD98059 and U0126 (for ERK1/2 signalling) and SB203580 (for p38 MAPK signalling) down-regulated IL-8 secretion from rHpHSP60-treated NOMO1 cells. An anti-Toll-like receptor (TLR)2 antibody or TLR2 small interfering RNA (siRNA) partially inhibited the secretion of IL-8, and anti-TLR2 antibody also suppressed activation of ERK and p38 MAPK in rHpHSP60-treated NOMO1 cells. These reactions were associated with nuclear factor-κB (NF-κB)-mediated transcriptional activation, since U0126, SB203580 and the anti-TLR2 antibody decreased NF-κB activation. Taken together, the results suggest that ERK and p38 MAPK signalling linked to the TLR2 recognition receptor in human monocytes may be an important pathway in H. pylori-HSP60-induced IL-8 secretion.

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