Serum Markers in Gluten Challenge

Study Overview
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Brief Summary
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The purpose of this research study is to evaluate non-invasive markers of celiac disease activity in subjects that are on a gluten-free diet, in remission from celiac disease who undergo gluten challenge. The secondary aims of this protocol are to identify novel mediators important in the pathophysiology of celiac disease and to evaluate changes in metabolism with gluten exposure.

Detailed Description
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The diagnosis of celiac disease carries with it important ramifications. Celiac disease is a systemic immunologic disorder in which the sentinel lesion is an enteropathy triggered by polypeptides derived primarily from the gliadin proteins found in wheat, rye and barley. Ingestion of the offending proteins leads to inflammation and intestinal mucosal damage, which results in a spectrum of abdominal symptoms, increased intestinal permeability, malabsorption, occult gastrointestinal bleeding and diarrhea. Systemic manifestations of celiac disease include a myriad of conditions including malignancy and autoimmune disease. The only accepted treatment for celiac disease is lifelong adherence to a gluten free diet. Adherence to this diet, simply put avoiding all foods containing even small amounts of wheat, rye and barley, has been shown to lead to improvement in the majority of related problems and normalization of all standard diagnostic tests. Because of this many individuals who present for evaluation of possible celiac disease but who are already on a gluten free diet cannot be tested accurately as there is currently no way of differentiating between healthy individuals and individuals with well treated celiac disease. The standard practice in such cases is to perform a 'Gluten Challenge' whereby the patient eats the equivalent of 2 slices of bread per day for six to eight weeks before returning for evaluation with serologic testing and endoscopy with duodenal biopsy. The use of the gluten challenge in clinical practice is limited by patient symptoms and resistance to such a long test period, after which it may take a number of weeks for the intestine to heal and the symptoms to resolve. Autoantibodies to tissue transglutaminase or antibodies to deamidated gliadin, while being excellent tools to predict celiac disease in patients who have been on a long-term gluten containing diet, display low sensitivities to detect short-term and/or recent gluten exposure. For this reason, it would be very useful if novel circulating markers could be identified that indicate the presence of celiac disease and in particular would provide an early and less invasive marker of a positive response to gluten challenge.

Official Title
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Circulating Markers of Celiac Disease Activity During Gluten Challenge - a Pilot Study.

Conditions
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Celiac Disease

Intervention / Treatment
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* Dietary Supplement: Gluten
* Dietary Supplement: Gluten


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 17 and 72 years, inclusive. Subject must have been diagnosed with celiac disease by duodenal / jejunal biopsy at least 6 months prior to entrance into the study. Subject has Anti-Tissue Transglutaminase (anti-tTG) ≤ 20 EU as measured by serology. Subject must be on a gluten-free diet for at least the past 6 months. Female subjects should be either post-menopausal (amenorrhea for at least 24 consecutive months), surgically sterile, or women of child-bearing potential (WOCP) with a negative urine beta human chorionic gonadotropin (HCG) pregnancy test prior to entering the study and who are using or agree to use acceptable methods of contraception. Abstinence is an acceptable means of avoiding pregnancy as long as the subject agrees to use contraception if they become sexually active. Acceptable contraceptives include intrauterine devices (IUDs), hormonal contraceptives (oral, depo, patch or injectable) in use for one month prior to screening and double barrier methods such as condoms or diaphragms with spermicidal gel or foam. Subject must sign an Institutional Review Board approved informed consent and agree to complete required clinic visits. BMI between 18.5 and 38, inclusive. Exclusion Criteria: Subject has Anti-Tissue Transglutaminase (anti-tTG) > 20 EU as measured by serology. Subject has other food intolerances or food allergies (other than celiac disease) that would interfere with the conduct of the study). Subject has a history of severe acute symptomatic reactions to sporadic gluten ingestion Subject has any chronic active GI disease other than celiac disease (e.g. Crohn's disease, IBS). Subjects with symptomatic neurological or psychiatric disease(s) that would interfere with the conduct of the study. Subject has clinically significant abnormal laboratory test results at the screening visit or as determined by the Principal Investigator Subject is pregnant or breast feeding. Subject (premenopausal females) is sexually active without contraception. Subject should not have been on steroids in the past 3 months. Subject is deemed inappropriate by the Principal Investigator.

Ages Eligible for Study
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Minimum Age: 17 Years
Maximum Age: 72 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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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low gluten group<br>Subjects will eat 3g of gluten per day | Dietary Supplement: Gluten<br>* 3g<br>|
| Experimental: High gluten group<br>Subjects will eat 10g of gluten per day | Dietary Supplement: Gluten<br>* 10g<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Crypt Depth to Villous Height Ratio | Histological evaluation of duodenal biopsy samples to evaluate crypt depth to villous height ratio. On the best oriented section of each biopsy fragment, villous height to crypt depth (Vh:Cd) ratio was determined by measuring the mean height /mean depth of adjacent villi/proliferative crypt zones at magnification 100x. Evaluations were considered discrepant Vh:Cd differed by more than 0.5. Overall, there was excellent concordance with the evaluations of the 165 biopsy fragments determined to be optimal for evaluation. The Vh:Cd ratios on individual biopsies from a single averaged to produce a representative Vh:Cd ratio for each endoscopy. Normal Vh:Cd ratio was regarded as 3:1 or greater. Adelman DC, Murray J, Wu TT, Mäki M, Green PH, Kelly CP. Measuring Change In Small Intestinal Histology In Patients With Celiac Disease. Am J Gastroenterol. 2018 Mar;113(3):339-347. doi: 10.1038/ajg.2017.480. Epub 2018 Feb 20. Review. PubMed PMID: 29460921. | Screening (Day -7 to -14), Day 3, Day 14 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Count of Intraepithelial Lymphocytes Per 100 Enterocytes in Duodenal Biopsy Samples | On the best oriented section of each biopsy fragment , the number of intraepithelial lymphocytes (IEL count) per 100 enterocytes was recorded at magnification 400x. IEL counts were considered discrepant if a difference of >10 IELs existed between counts. Overall, there was excellent concordance with the evaluations of the 165 biopsy fragments determined to be optimal for evaluation. The IEL counts on individual biopsies from a single endoscopy were averaged to produce a representative IEL count for each endoscopy. Adelman DC, Murray J, Wu TT, Mäki M, Green PH, Kelly CP. Measuring Change In Small Intestinal Histology In Patients With Celiac Disease. Am J Gastroenterol. 2018 Mar;113(3):339-347. doi: 10.1038/ajg.2017.480. Epub 2018 Feb 20. Review. PubMed PMID: 29460921. | Screening (Day -7 to -14), Day 3, Day 14 | 
| Measures of Intestinal Permeability (Urinary Lactulose to Mannitol Ratio) | LAMA evaluation has been reported to be an accurate measure of small intestinal mucosal permeability though assessment of differential absorption of lactulose and mannitol. For LAMA testing, a solution containing 7.5 g lactulose and 2 g mannitol in 100 mL of water was ingested by the participants in the evening after visit 1 and in the evening before each other study visit. The participants were asked to fast for at least 4 h and to void completely before drinking the sugar solution, then fast overnight and collect all overnight and morning urine. Urine sample analyzed for lactulose and mannitol using standardized methodology by liquid chromatography-tandem mass spectrometry. | Screening (Day -7 to -14), Day 0, Day 3, Day 7, Day 14, Day 28 | 
| Measures of Immune Activation | IgA anti-human tissue transglutaminase assay (Inova Diagnostics, Inc., San Diego, USA): negative <20, borderline 20-30, positive >30. IgA/IgG anti- DGP assay : NEGATIVE <20, BORDERLINE 20-30, POSITIVE >30 METHOD IS INOVA ANTI-DEAMIDATED GLIADIN PEPTIDE IGA/IGG. | Screening (Day -7 to -14), Day 0, Day 3, Day 7, Day 14, Day 28 | 
| Assessment of Protein Expression in Intestinal Biopsies | Proportion of participants responding to a gluten challenge. Tissue transglutaminase (tTG) scoring: NEGATIVE <20, BORDERLINE 20-30, POSITIVE >30. Deamidated gliadin peptide (DGP) scoring: NEGATIVE <20, BORDERLINE 20-30, POSITIVE >30 METHOD IS INOVA ANTI-DEAMIDATED GLIADIN PEPTIDE IGA/IGG. | Screening (Day -7 to -14), Day 3, Day 14 | 
| Symptomatic Response to Gluten Exposure Determined by Celiac Symptom Index Questionnaire | CSI (Celiac Symptom Index) scores range from 7-80. Higher scores indicate greater degree of symptoms CSI: Leffler DA, Dennis M, Edwards George J, Jamma S, Cook EF, Schuppan D, Kelly CP. A validated disease-specific symptom index for adults with celiac disease. Clin Gastroenterol Hepatol. 2009;7:1328-34. PubMed PMID: 19665584. | Screening (Day -7 to -14), Day 0, Day 3, Day 7, Day 14, Day 28 | 
| Assessment of Protein Expression in Intestinal Biopsies Using Marsh Scores | Proportion of participants responding to a gluten challenge. Tissue transglutaminase (tTG) scoring: NEGATIVE <20, BORDERLINE 20-30, POSITIVE >30. Deamidated gliadin peptide (DGP) scoring: NEGATIVE <20, BORDERLINE 20-30, POSITIVE >30 METHOD IS INOVA ANTI-DEAMIDATED GLIADIN PEPTIDE IGA/IGG. | Screening (Day -7 to -14), Day 3, Day 14 | 
| Symptomatic Response to Gluten Exposure Determined by Gastrointestinal Symptom Rating Scale | Measure Description: GSRS (Gastrointestinal Symptom Rating Scale) scores range 15-105 with higher scores indicating greater degree of symptoms GSRS: Svedlund J, Sjödin I, Dotevall G. GSRS--a clinical rating scale for gastrointestinal symptoms in patients with irritable bowel syndrome and peptic ulcer disease. Dig Dis Sci. 1988;33(2):129-134. doi:10.1007/BF01535722 | Screening (Day -7 to -14), Day 0, Day 3, Day 7, Day 14, Day 28 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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celiac disease, gluten challenge