Trial reportGut2008
Correlation of T cell response and bacterial clearance in human volunteers challenged with Helicobacter pylori revealed by randomised controlled vaccination with Ty21a-based Salmonella vaccines.
Trial report in Gut, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 50 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
50 citing papers in PubMed, 1 synthesis or guideline pooled it, 134 citations in OpenAlex.
- Bibliometric analysis ofFrontiers in microbiology · 2025Pooled it
- Mucosal Inducible NO Synthase-Producing IgA+ Plasma Cells in Helicobacter pylori-Infected Patients.Journal of immunology (Baltimore, Md. : 1950) · 2016Trial
- Developing Antiviral Vaccines Based on AttenuatedPathogens (Basel, Switzerland) · 2026Review
- Review
- Mucosal vaccination with enzymatically activeFrontiers in microbiology · 2026Article
- Gastric Inflammation Impacts Serotonin Secretion in a Mouse Model ofInternational journal of molecular sciences · 2025Article
- Editorial: Mucosal immunity after vaccination.Frontiers in immunology · 2025Article
- Developing a potent vaccine againstExpert reviews in molecular medicine · 2024Review
- Probing the expression and adhesion of glycans involved in Helicobacter pylori infection.Scientific reports · 2024Article
- Antibiotic Resistance ofJournal of Korean medical science · 2024Review
- Solid Lipid Nanoparticles Delivering a DNA Vaccine EncodingInternational journal of molecular sciences · 2024Article
- Helicobacter pylori.Current topics in microbiology and immunology · 2024Review
- Review
- Article
- How Long Will It Take to Launch an EffectiveInfection and drug resistance · 2023Review
- Oral Administration of aFrontiers in immunology · 2022Article
- Experimental human hookworm infection: a narrative historical review.PLoS neglected tropical diseases · 2021Review
- Article
- Defining theFrontiers in microbiology · 2020Article
- The frequency of circulating integrin α4β7Helicobacter · 2019Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
16 authors at 5 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundHelicobacter pylori remains a global health hazard, and vaccination would be ideal for its control. Natural infection appears not to induce protective immunity. Thus, the feasibility of a vaccine for humans is doubtful.
methodsIn two prospective, randomised, double-blind, controlled studies (Paul Ehrlich Institute application nos 0802/02 and 1097/01), live vaccines against H pylori were tested in human volunteers seronegative for, and without evidence of, active H pylori infection. Volunteers (n = 58) were immunised orally with Salmonella enterica serovar Typhi Ty21a expressing H pylori urease or HP0231, or solely with Ty21a, and then challenged with 2x10(5) cagPAI(-) H pylori. Adverse events, infection, humoral, cellular and mucosal immune response were monitored. Gastric biopsies were taken before and after vaccination, and postchallenge. Infection was terminated with antibiotics.
resultsVaccines were well tolerated. Challenge infection induced transient, mild to moderate dyspeptic symptoms, and histological and transcriptional changes in the mucosa known from chronic infection. Vaccines did not show satisfactory protection. However, 13 of 58 volunteers, 8 vaccinees and 5 controls, became breath test negative and either cleared H pylori (5/13) completely or reduced the H pylori burden (8/13). H pylori-specific T helper cells were detected in 9 of these 13 (69%), but only in 6 of 45 (13%) breath test-positive volunteers (p = 0.0002; Fisher exact test). T cells were either vaccine induced or pre-existing, depending on the volunteer.
conclusionChallenge infection offers a controlled model for vaccine testing. Importantly, it revealed evidence for T cell-mediated immunity against H pylori infection in humans.
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.