Evaluation of the Sphingolipid Metabolite S1P as a Novel Biomarker in Food Allergy

Study Overview
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Brief Summary
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Food allergies represent an increasing health concern in the industrialized countries and especially affect pediatric patients. In this population adverse reactions against food compounds can lead to anaphylactic reactions. Despite substantial research efforts, clinical markers predicting disease severity and symptoms are missing to date. Recent studies have revealed that sphingolipids, especially sphingosine-1-phosphate (S1P), play an essential role in allergy. It was reported that asthmatic patients have higher S1P levels in bronchiallavage fluids after allergen challenge. First experimental studies revealed a correlation of S1P and the outcome of anaphylaxis. Furthermore, we have shown in our recent mouse study that S1P homeostasis is pivotal for food allergy induction and effector cell response. Therefore, it is the aim of the presented pilot project to evaluate whether S1P serum titers are altered in food allergic children and if the S1P levels correlate with the outcome of anaphylaxis during double blind placebo controlled food challenges (DBPCFCs).

Official Title
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The Role of Sphingosine-1-phosphate in Food Allergy - Biomarker for Disease Severity and Anaphylaxis Outcome

Conditions
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Food Allergy, Anaphylaxis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients between 1-17 years who have been reported to suffer from food allergic reactions and who are subjected to DBPCFC or open provocation Patients who are diagnosed by elevated allergen specific IgE and/or positive skin prick testing Willingness to participate in the study Exclusion Criteria: Refusal to participate in the study Non-IgE-mediated food allergy

Ages Eligible for Study
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Minimum Age: 12 Months
Maximum Age: 17 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 |
| --- | --- |
| food allergic<br>positive reaction during DBPCFC | |
| Non-food allergic<br>no reaction during DBPCFC | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| S1P in allergic and non-allergic patients before and after challenge | The primary endpoint of this study is the measurement of S1P in allergic and non-allergic patients before and after challenge. | up to 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of allergic mediators and correlation with S1P levels | Evaluation of allergic mediators like histamine, human mast cell tryptase and eosinophil cationic protein and correlate these results with the levels of S1P within the group and between allergic and non-allergic patients | up to 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anaphylaxis, Food allergy, Sphingosine-1-phosphate, Biomarker, Double-blind placebo-controlled food challenge