Genetic diversity of the Campylobacter genes coding immunodominant proteins

Pawelec, D

doi:10.1016/s0378-1097(00)00067-7

Cited by 18 publications

(26 citation statements)

References 16 publications

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“…The surface antigen, CjaA protein, found to be secreted by C. ureolyticus UNSWCD (Table 1) is a surface-exposed protein which is homologous to ABC transport proteins and is highly immunodominant in C. jejuni (23). The ABC transport system transports substrates across the periplasm to maintain lipid asymmetry, which is critical to the cell membrane in Gram-negative bacteria (12).…”

Section: Effect Of C Ureolyticus Unswcd Infection and Cytokines On Imentioning

confidence: 99%

Pathogenic Potential of Campylobacter ureolyticus

et al. 2012

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The recent detection and isolation of the aflagellate Campylobacter ureolyticus (previously known as Bacteroides ureolyticus) from intestinal biopsy specimens and fecal samples of children with newly diagnosed Crohn's disease led us to investigate the pathogenic potential of this bacterium. Adherence and gentamicin protection assays were employed to quantify the levels of adherence to and invasion into host cells. C. ureolyticus UNSWCD was able to adhere to the Caco-2 intestinal epithelial cell line with a value of 5.341% ؎ 0.74% but was not able to invade the Caco-2 cells. The addition of two proinflammatory cytokines, tumor necrosis factor alpha (TNF-␣) and gamma interferon (IFN-␥), to the cell line did not affect attachment or invasion, with attachment levels being 4.156% ؎ 0.61% (P ‫؍‬ 0.270) for TNF-␣ and 6.472% ؎ 0.61% (P ‫؍‬ 0.235) for IFN-␥. Scanning electron microscopy visually confirmed attachment and revealed that C. ureolyticus UNSWCD colonizes and adheres to intestinal cells, inducing cellular damage and microvillus degradation. Purification and identification of the C. ureolyticus UNSWCD secretome detected a total of 111 proteins, from which 29 were bioinformatically predicted to be secretory proteins. Functional classification revealed three putative virulence and colonization factors: the surface antigen CjaA, an outer membrane fibronectin binding protein, and an S-layer RTX toxin. These results suggest that C. ureolyticus has the potential to be a pathogen of the gastrointestinal tract.

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Section: Effect Of C Ureolyticus Unswcd Infection and Cytokines On Imentioning

confidence: 99%

Pathogenic Potential of Campylobacter ureolyticus

et al. 2012

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“…C. jejuni flagella play multiple roles in pathogenesis (12) and prior studies have shown that a flagellin-based vaccine was immunogenic and protective in animal models (17). However, the heterogeneity of flagellin among C. jejuni strains and the high conservation of some domains of C. jejuni flagellin with other bacterial flagellins (20) suggest that this may not be an ideal subunit vaccine. C. jejuni strains lack specialized type three secretion systems and, instead, flagella secrete a number of nonflagellar protein substrates that modulate virulence.…”

mentioning

confidence: 99%

Immunogenicity and Protective Efficacy of Recombinant Campylobacter jejuni Flagellum-Secreted Proteins in Mice

et al. 2008

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“…Omp18 is a peptidoglycan-associated lipoprotein precursor which is structurally related to Omp18 of Campylobacter jejuni and to Omp22 (HP0923) of H. pylori. In C. jejuni, Omp18 is an immunodominant antigen which is used for vaccination trials in chickens (20,27). Nevertheless, the sequence homology to H. pylori Omp18 is low.…”

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confidence: 99%

Antigenic Properties of HpaA and Omp18, Two Outer Membrane Proteins ofHelicobacter pylori

Voland¹,

Hafsi²,

Zeitner³

et al. 2003

Infect Immun

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Outer membrane proteins (OMPs) are incorporated into the outer plasma membrane of Helicobacter pylori and are important for, e.g., ion transport, adherence, structural and osmotic stability, and bacterial virulence but may also be antigenic due to their surface exposure. Previous proteome-based approaches with H. pylori lysates determined a strong serological reaction towards two H. pylori OMPs, HpaA (TIGR HP0797) and Omp18 (TIGR HP1125). PCR was used to detect DNA encoding the two proteins, and a positive signal was found in all H. pylori strains tested. Proteins were cloned and expressed in the human kidney cell line HK293 with the QiaExpressionist system with a C-terminal His tag. Only sera from infected persons showed a positive reaction with the recombinant proteins. Recombinant HpaA (rHpaA) and rOmp18 were incubated with human peripheral blood mononuclear cells and induced secretion of interleukin-12 (IL-12) and IL-10 from these cells. To determine the effect on antigen-presenting cells, human blood monocytic and dendritic cells (DCs) were isolated by magnetic cell separation. rOmp18 and rHpaA strongly stimulated major histocompatibility class II and CD83 expression 7-to 10-fold on isolated DCs. rHpaA and rOmp18 failed to stimulate IL-8 secretion from monocytes but increased secretion of IL-12 and IL-10 from DCs significantly. In summary, HpaA and Omp18 are recognized by human dendritic cells and induce their maturation as well as antigen presentation. HpaA and Omp18 of H. pylori thereby appear to have a specific antigenic potential in humans.

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Genetic diversity of the Campylobacter genes coding immunodominant proteins

Cited by 18 publications

References 16 publications

Pathogenic Potential of Campylobacter ureolyticus

Pathogenic Potential of Campylobacter ureolyticus

Immunogenicity and Protective Efficacy of Recombinant Campylobacter jejuni Flagellum-Secreted Proteins in Mice

Antigenic Properties of HpaA and Omp18, Two Outer Membrane Proteins ofHelicobacter pylori

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