Skin Testing With Recombinant Bet v 1 and Hypoallergenic Recombinant Bet v 1 Fragments

December 6, 2015 updated by: Stefan Woehrl

Skin Testing With Recombinant Bet v 1 and Hypoallergenic Recombinant Bet v 1 Fragments to Dissect the Contribution of IgE to Chronic Allergic Skin Inflammation

Aim of this study is to use the major allergen 1 of birch-tree pollen (Bet v 1, Betula verrucosa, synonymous Betula pendula), to investigate the contribution of immunoglobulin E (IgE)- versus non-IgE-mediated mechanisms to chronic skin inflammation in atopic dermatitis patients.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

In this study non-IgE-reactive recombinant Bet v 1 (rBet v 1) fragments (F1: aa 1-74; F2: aa 75-160) and the fully IgE-reactive recombinant Bet v 1 (aa 1-160)will be used for skin prick testing and atopy patch testing in birch pollen allergic patients with birch pollen induced exacerbation of atopic dermatitis. For control purposes birch pollen allergic patients without birch pollen-induced atopic eczema, persons with allergies other than to birch and non-allergic people will be tested.

The individuals will be subjected to in vivo skin prick and atopy patch testing with rBet v 1, rBet v 1 fragment 1, rBet v 1 fragment 2 and an equimolar mix of the rBet v 1 fragments. In parallel, the IgE reactivity, and in vitro T cell proliferation, and cytokine production will be studied. Those analyses should help to determine the relevance of IgE mediated mechanisms to chronic skin inflammation and T cell proliferation in AD patients.

A staining for the surface markers chemokine receptor (CCR4)+ and cutaneous lymphocyte antigen (CLA)+ which reportedly are enriched in inflamed skin will further allow to investigate whether patients with high numbers of T lymphocytes expressing CCR4 and CLA tend to exhibit stronger skin inflammation. Moreover, allergen-specific antibody and T cell responses will be analyzed 6-8 weeks after the epicutaneous allergen application.

Study Type

Observational

Enrollment (Actual)

30

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Vienna, Austria, 1090
        • Medical University of Vienna

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (ADULT, OLDER_ADULT)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Different types of individuals will be recruited and divided in four groups. A total of 30 allergic and non-allergic persons will be included in this study:

patients with Birch pollen-related atopic dermatitis (AD), Birch pollen allergic patients without AD (group 2), allergic individuals without birch pollen allergy and non-allergic individuals.

Description

Inclusion Criteria:

  1. Age between 18 and 75 years
  2. They will be available to complete the study

Exclusion Criteria:

  1. Severe general maladies
  2. Severe skin inflammation in the test area
  3. Risk of non-controllable general reaction
  4. Pregnancy and breast-feeding
  5. Autoimmune diseases, immune-defects including immuno-suppression, immune-complex-induced immunopathies
  6. Contra-indication for adrenaline
  7. Patients under long-term treatment with systemic corticosteroids immunosuppressive drugs, tranquilizers or psychoactive drugs
  8. Positive IgE reaction on hypoallergenic Bet v 1 derivatives
  9. The subject is currently participating in another clinical study in which the subject is or will be exposed to an investigational or a non-investigational drug.
  10. The subject is at risk of non-compliance with the study procedures/restrictions

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Four (4)

Group 1: Birch pollen-related atopic dermatitis (AD) (n=15) Group 2: Birch pollen allergic patients without AD (n=5) Group 3: Allergic individuals without birch pollen allergy (n=5) Group 4: Non-allergic individuals (n=5)

Patients will be tested by SPT and APT:

SPT: Histamine, buffer, commercial birch pollen extract, rBet v 1, rBet v 1 fragment 1, rBet v 1 fragment 2, and equimolar rBet v 1 fragment mix (20 and 40 μg/ml) in duplets.

APT: birch pollen extract, rBet v 1, rBet v 1 fragment 1, rBet v 1 fragment 2, equimolar mix of rBet v 1 fragments (160 μg/application); negative control with vaseline

All patients will be tested by skin prick testing (SPT: Histamine, buffer, commercial birch pollen extract, rBet v 1 (20 and 40 μg/ml), rBet v 1 fragment 1 (20 and 40 μg/ml), rBet v 1 fragment 2 (20 and 40 μg/ml), equimolar rBet v 1 fragment mix (20 and 40 μg/ml) in duplets.

Atopy patch testing (APT: birch pollen extract, rBet v 1:160 μg/application, rBet v 1 fragment 1: 160 μg/application, rBet v 1 fragment 2: 160 μg/ml, equimolar mix of rBet v 1 fragments: 160 μg/application; negative control with vaseline alone.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Participants with Positive Atopy Patch Testing Reactions of Each Grade on the European Task Force on Atopic Dermatitis Scale
Time Frame: 6 months
Birch pollen extract (BPE), as well as rBet v 1 (160mg), rBet v 1 fragment 1 (160mg), rBet v 1 fragment 2 (160mg), and an equimolar rBet v 1 fragment mix (80mg of each rBet v 1 fragment), were applied for 48h in patch test chambers onto nonlesional skin on the backs of the subjects. After 48h, patches were removed, and reactions were analyzed and photodocumented. Grading of positive APT reactions (i.e., reactions of more than 4 mm in diameter) was done according the European Task Force on Atopic Dermatitis by a blinded investigator: -, negative result; ?, only erythema, questionable; +, erythema, infiltration; ++, erythema, few papules (<3); +++, erythema, papules from 4 to less than many; ++++, erythema, many or spreading papules; or +++++, erythema, vesicles.
6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Study Chair: Rudolf Valenta, MD, Medical University of Vienna

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

February 1, 2011

Primary Completion (ACTUAL)

November 1, 2011

Study Completion (ACTUAL)

April 1, 2013

Study Registration Dates

First Submitted

July 26, 2011

First Submitted That Met QC Criteria

March 25, 2014

First Posted (ESTIMATE)

March 28, 2014

Study Record Updates

Last Update Posted (ESTIMATE)

December 8, 2015

Last Update Submitted That Met QC Criteria

December 6, 2015

Last Verified

December 1, 2015

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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