Seroreactivity to specific antigens of Helicobacter pylori infection is associated with an increased risk of the dyspeptic gastrointestinal diseases

SummaryObjectivesThe correlation between seroreactivity to Helicobacter pylori-specific antigens and clinical outcomes in gastrointestinal disease remains unresolved. We investigated the anti-H. pylori antibody profile in northeast Thai dyspeptic patients with gastrointestinal disease in order to identify any H. pylori antigens that may be associated with an increased risk of gastrointestinal disease.Patients and methodsEighty-nine H. pylori-infected dyspeptic patients (44 non-ulcer, 23 peptic ulcer, 22 gastric cancer) were included in the study. Patients were considered to have H. pylori infection when at least one invasive method (i.e., culture, rapid urease test, and histology on biopsy specimens) and serological tests including a commercial ELISA (Pyloriset EIA-GIII) and a commercial immunoblot (Helicoblot 2.1; Genelabs Diagnostics), were positive. In addition, the sera of 20 H. pylori-infected blood donors and 10 H. pylori-non-infected blood donors were also randomly collected and analyzed for H. pylori infection by ELISA and Helicoblot 2.1.ResultsImmunoreactive protein bands at 116-kDa, 89-kDa, 37-kDa, 35-kDa, 30-kDa, 19.5-kDa, and the current infection marker for H. pylori-infected patients had average frequencies of 97.8%, 77.5%, 36.0%, 25.8%, 79.8%, 58.4%, and 69.7%, respectively. The immunoreactive patterns obtained from the H. pylori-infected patients and H. pylori-infected blood donors were similar. The antibodies to VacA and CagA antigens were not significantly different among the H. pylori-infected gastroduodenal patient groups. The simultaneous presence of antibody to 19.5-kDa antigen and absence of antibody to 35-kDa antigen was associated with an increased risk of gastric cancer (p<0.05). The immunoreactive band to 35-kDa antigen was found at significantly higher levels in peptic ulcer patients, and the 37-kDa antigen was found at significantly higher levels in non-ulcer patients (both p<0.05). Significantly low levels of antibodies to 23-kDa and 85-kDa antigens were found associated with peptic ulcer (p<0.05).ConclusionsWe confirm that the universal presence of CagA and VacA in H. pylori-infected patients in Thailand is independent of the gastroduodenal disease. The presence or absence of antibodies to H. pylori-specific antigens may be useful as indirect markers in the screening of H. pylori-infected patients, and may have specific protection roles in H. pylori-related gastroduodenal diseases

3697/N

Abstract. Helicobacter pylori, an important etiological agent in the development of gastritis, peptic ulcer and gastric carcinoma, can be detected by the enzyme-linked immunosorbent assay (ELISA). Our objectives were: 1) to evaluate the efficacy of a commercial ELISA kit (Pyloriset EIA-G III) in sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for diagnosis of H. pylori infection in Thai dyspeptic patients in Khon Kaen Thailand; and 2) to examine the seroprevalence of H. pylori among blood donors at Srinagarind Hospital&apos;s Blood Bank, Khon Kaen University, by the commercial ELISA. Gastric biopsies obtained from 137 dyspeptic patients were diagnosed by culture, rapid urease test (RUT) and histology. Serum samples from the same dyspeptic patients and 100 healthy blood donors were assayed using the commercial ELISA. H. pylori infection in dyspeptic patients was considered positive when the culture or both RUT and histology were positive. Using a cut-off value at a titer of 20 U/ml (as recommended by the manufacturer), we found the commercial ELISA kit had a sensitivity of 93.3%, specificity of 75.3%, PPV of 74.7%, NPV of 93.5% and accuracy of 83.2%. The overall H. pylori seroprevalence in the healthy blood donors was 57%. Of the 100 healthy blood donors, 39 (60.9%) of the males and 18 (50.0%) of the females were seropositive

<i>Burkholderia pseudomallei</i> Biofilm Promotes Adhesion, Internalization and Stimulates Proinflammatory Cytokines in Human Epithelial A549 Cells - Fig 1

<p><b>(A)</b> Fluorescence microscopic views of the 2-day biofilms of <i>B</i>. <i>pseudomallei</i> H777, M10 and C17 grown statically on glass slides in LB broth at 37°C. The biofilms were stained with FITC-ConA and monitored under a Nikon Eclipse Ni-U fluorescence microscope (20× magnification). Strains H777 and C17 showed aggregation of surface-adherent bacteria whereas the biofilm mutant, M10, was rarely attached on the glass slide. (B) Confocal laser scanning micrographs of the 2-day biofilms of <i>B</i>. <i>pseudomallei</i> H777, M10 and C17 grown statically on glass slides in LB broth at 37°C. The biofilms were stained with FITC-ConA. The crossing lines in each images (x and y axes) indicate the correspondent vertical CLSM section (Z), indicating the thickness of the biofilm. The bars indicate 5 μm. The images were taken using a Zeiss 500 and a Zeiss 800 CLSM microscope (100× magnification).</p

Intracellular survival and multiplication of <i>B</i>. <i>pseudomallei</i> H777, M10 and C17 strains in human lung epithelial cells at MOI 10.

<p>The number of bacteria present were enumerated at 4, 8 and 12 h p.i. using the drop plate technique. Data are represented as means ± standard deviation from at least three independent experiments in triplicate wells.</p

Cytokine production by human lung epithelial cells (A549) in response to infection with <i>B</i>. <i>pseudomallei</i> H777, M10 and C17 strains.

<p>A549 cells were infected at MOI 10 and MOI 100. The culture supernatants were harvested at 8 h p.i. to measure cytokine levels. Data represent the means ± standard errors for triplicate wells of single representative experiments. Each experiment was performed at least three times. Asterisks denote statistical significance (<i>p</i> < 0.05).</p

Adhesion of <i>B</i>. <i>pseudomallei</i> H777, M10 and C17 to human lung epithelial cells at MOI 10.

<p>(A) Percentages of bacterial adhesion were determined by comparing the number of adherent bacteria to the inoculum. The numbers of CFU of cell-associated bacteria were counted after 1 h p.i. using the drop plate technique. Data represent the mean ± standard deviation of triplicates from at least three independent experiments. Asterisks denote statistical significance relative to H777 (<i>p</i> < 0.05). (B) Light microscopic images demonstrating <i>B</i>. <i>pseudomallei</i> H777, M10 and C17 adhesion to A549 cells. Bar represents 10 μm. Representative images from Giemsa stained specimens and visualized under 100× magnification.</p