Pathogen-microbiome Interaction During Helicobacter Pylori Infection

Study Overview
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Brief Summary
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Helicobacter pylori affects the gut microbiome in ways that are only partially understood. In which patients H. pylori causes severe disease and in whom it merely colonizes, possibly even with beneficial effects, is not understood. The investigators are pursuing the hypothesis that changes in the gut microbiome that can be easily measured in stool have such predictive value.

Detailed Description
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Helicobacter pylori colonizes the stomach of about half of the world's population, including about 20-30% of adults in Germany. In some cases, this colonization can lead to chronic inflammation of the gastric mucosa, which can lead to various serious diseases such as ulcer disease and gastric cancer. It has been reported several times in the literature that Helicobacter pylori infection negatively affects the human intestinal flora and can lead to microbial imbalance (dysbiosis). Recent studies, mostly from mouse models, reveal new roles and interactions of the microbiome: host immune response may influence bacterial activity; bacterial metabolites may determine microbiome functions. Differences in the microbiome were also found between Helicobacter pylori-infected patients and were associated with treatment success. On the other hand, beneficial microbial symbiosis may prevent intestinal inflammation. The reasons for these differences in the microbiome of Helicobacter pylori-infected patients, which may also contribute to treatment failure, remain to be investigated. Therefore, this project aims to investigate how Helicobacter pylori affects the bacteria and fungi of the human gastrointestinal microbiome and how the suspected microbial imbalance may influence treatment success. In this project, The investigators aim to answer the question of how these newly discovered mechanisms alter the course of human H. pylori infection. The investigators will analyze H. pylori itself in colonized patients and asymptomatic individuals (whole genome sequencing), determine the immune response of the carrier (RNA expression in lymphocytes), and composition of the gut microbiome (DNA sequencing) and activity (RNA expression in the bacteria/fungi and identification of metabolites). Using bioinformatics approaches, particularly machine learning, The investigators will determine the parameters that predict disease progression and eradication success. The results will provide important decision support for H. pylori-infected patients.

Official Title
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Pathogen-microbiome Interaction in Human Response and Disease-outcome During Infection and Colonization With Helicobacter Pylori

Conditions
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Helicobacter Pylori Infection

Intervention / Treatment
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* Diagnostic Test: Analysis of gut microbiome and immune signatures


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients: - Male and female patients aged ≥ 18 years. Specimens from patients undergoing tissue sampling, stool, and blood to rule out Helicobacter pylori infection Written informed consent from patients. Volunteer subjects: - Male and female (non-pregnant) volunteers between the ages of 18-65 years. Written informed consent from volunteers. No acute medical conditions No regular medication use, and no antibiotic use in the last 4 weeks. Exclusion Criteria: Patients: - Minor patients Patients not capable of giving consent Samples without sufficient residual material after standard diagnostic procedures Samples from patients who have not given consent for testing Volunteer subjects: - Subjects not capable of giving consent Subjects with acute illnesses Subjects older than 65 or younger than 18 years of age. Pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Helicobacter pylori patients<br>Patients with gastric biposies which was positive for Helicobacter pylori in culture | Diagnostic Test: Analysis of gut microbiome and immune signatures<br>* The investigators will analyse the microbiome composition (16S rDNA-sequencing and metagenomics), microbiome activity (RNA-sequencing of stool bacteria and metabolite sampling) and immune cell activity (leukocyte RNA-sequencing) of all study groups.<br>|
| Helicobacter pylori asymptomatic carriers<br>Healthy controls who are positive for Helicobacter pylori antigen in stool and have no symptoms of gastritis | Diagnostic Test: Analysis of gut microbiome and immune signatures<br>* The investigators will analyse the microbiome composition (16S rDNA-sequencing and metagenomics), microbiome activity (RNA-sequencing of stool bacteria and metabolite sampling) and immune cell activity (leukocyte RNA-sequencing) of all study groups.<br>|
| Healthy controls<br>Healthy controls who are negative for Helicobacter pylori antigen in stool and have no symptoms of gastritis | Diagnostic Test: Analysis of gut microbiome and immune signatures<br>* The investigators will analyse the microbiome composition (16S rDNA-sequencing and metagenomics), microbiome activity (RNA-sequencing of stool bacteria and metabolite sampling) and immune cell activity (leukocyte RNA-sequencing) of all study groups.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Helicobacter pylori microbiome and immune signatures | The diversity of the gut microbial species of patients and controls as well as transcriptomic signatures of blood immune cells will be assessed and compared to conclude specisifc signatures that are associated with the disease and carrier status. These signatures will be analyzed to identify specific bacterial and immune biomarkers that can be used as a screening tool for Helicobacter pylori infection. | 12-18 Months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Helicobacter pylori eradication control | Patients with positive gastric biopsy for Helicobacter pylori will be assessed for successful eradication after treatment, and the eradication success will be compared with the patients' microbial signatures to identify specific gut microbial signatures that are associated with treatment outcome. | 12-24 Months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Helicobacter Pylori, Metagenomics