Innate Immunity in Eosinophilic Esophagitis

Study Overview
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Brief Summary
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The main aim of this study is to assess the expression of innate lymphoid cells in the esophageal mucosa of children with eosinophilic esophagitis (EoE) and in control subjects

Detailed Description
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Children (aged 1 to 18 years) presenting with symptoms suggestive of EoE and requiring an upper gastrointestinal endoscopy with biopsies of the esophageal mucosa in order to confirm or exclude the diagnosis of EoE will be included. Children paired for age in whom an endoscopy performed to explore symptoms of EoE revealed another condition (peptic oesophagitis, achalasia), or children paired for age in whom an endoscopy with biopsies has been performed to explore chronic abdominal or epigastric pain or suspected chronic inflammatory bowel disease, will be include as control subjects. The endoscopy will be performed under general anaesthesia using a flexible endoscope with an external diameter of between 4.9 and 9.2 mm, depending on the size of the child. In line with the guidelines, eight biopsies will be collected from the proximal, median and distal oesophagus for the routine analysis of esophageal remodelling and inflammation. Three of these biopsies will be used in the context of this study to analyse innate immune cells using flow cytometry and to determine the profile of cytokine expression. Two biopsies will be placed in sterile, 0.5 ml Nunc tubes containing a storage buffer (MACS® Tissue Storage Solution) and then stored in ice until the extraction of cells for cytometric analysis. The third specimen will be placed in a sterile tube and frozen immediately in liquid nitrogen for analyses of the esophageal microbiome. ILC1, 2 and 3 and their sub-types will be identified by means of structural criteria (size and granularity) and differential membrane and intracellular labelling using the specific markers shown below. All acquisitions and analyses will be achieved using a 13-colour NovoCyte cytometer (AACEA) and its associated software (NovoAxpressTM), which are available in the laboratory.

Official Title
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Innate Lymphoid Cells in Eosinophilic Esophagitis (French Title : Cellules Lymphoïdes innées Dans l'Oesophagite à Eosinophiles)

Conditions
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Eosinophilic Esophagitis

Intervention / Treatment
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* Other: Endoscopy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: children 1-18 years presenting with symptoms suggestive of EoE requiring an upper gastrointestinal endoscopy with biopsies of the esophageal mucosa in order to confirm or exclude the diagnosis Children paired for age in whom an endoscopy performed to explore symptoms of EoE revealed another condition (peptic oesophagitis, achalasia), or children paired for age in whom an endoscopy with biopsies has been performed to explore chronic abdominal or epigastric pain or suspected chronic inflammatory bowel disease, will be include as control subjects Exclusion Criteria: immune deficiency auto immune diseases

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| case : eosinophilic esophagitis<br>Children with symptoms suggestive of EoE and requiring an upper gastrointestinal endoscopy with biopsies of the esophageal mucosa | Other: Endoscopy<br>* The endoscopy will be performed under general anaesthesia using a flexible endoscope with an external diameter of between 4.9 and 9.2 mm, depending on the size of the child. In line with the guidelines, eight biopsies will be collected from the proximal, median and distal oesophagus for the routine analysis of esophageal remodelling and inflammation. Three of these biopsies will be used in the context of this study to analyse innate immune cells using flow cytometry and to determine the profile of cytokine expression. Two biopsies will be placed in sterile, 0.5 ml Nunc tubes containing a storage buffer (MACS® Tissue Storage Solution) and then stored in ice until the extraction of cells for cytometric analysis . The third specimen will be placed in a sterile tube and frozen immediately in liquid nitrogen for analyses of the esophageal microbiome.<br>|
| control<br>Children in whom an endoscopy performed to explore symptoms of EoE revealed another condition (peptic oesophagitis, achalasia), or children in whom an endoscopy with biopsies has been performed to explore chronic abdominal or epigastric pain or suspected chronic inflammatory bowel disease | Other: Endoscopy<br>* The endoscopy will be performed under general anaesthesia using a flexible endoscope with an external diameter of between 4.9 and 9.2 mm, depending on the size of the child. In line with the guidelines, eight biopsies will be collected from the proximal, median and distal oesophagus for the routine analysis of esophageal remodelling and inflammation. Three of these biopsies will be used in the context of this study to analyse innate immune cells using flow cytometry and to determine the profile of cytokine expression. Two biopsies will be placed in sterile, 0.5 ml Nunc tubes containing a storage buffer (MACS® Tissue Storage Solution) and then stored in ice until the extraction of cells for cytometric analysis . The third specimen will be placed in a sterile tube and frozen immediately in liquid nitrogen for analyses of the esophageal microbiome.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The numbers of innate immune cells | The counts of innate immune cells will be compared between EoE patients and controls | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Microbiota | Analyses of the composition of the esophageal microbiome will be performed using 16S rDNA sequencing after the extraction of DNA according to published protocols and/or using commercial kits (QlAamp DNA stool Mini Kit; QIAGEN). The pyrosequencing of 16S DNA, the identification of groups and phyla and initial biostatistical analyses will be carried out by specialised platforms. | 1 year | 
| Metabolomics | Metabolomic analyses will be performed on plasma and red blood cell extracts using a device such as an Orbitrap-Exactive equipped with an electrospray source. The data will be analysed using data processing tools available in the laboratory (software systems for signal detection and automatic alignment, annotation and statistical analysis) | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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children, eosinophilic esophagitis, innate immunity