Innate Immunity in Eosinophilic Esophagitis
Condition: Eosinophilic Esophagitis
MeSH terms: Esophagitis; Eosinophilic Esophagitis
Study type: Observational

Summary: 
      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: 
      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.
    

Intervention name(s): Endoscopy
Intervention type(s): Other
Intervention description(s): 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.
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Children presenting with symptoms suggestive of EoE and requiring an upper gastrointestinal
        endoscopy with biopsies of the esophageal mucosa
      
Keywords: eosinophilic esophagitis; children; innate immunity