Koebner's Phenomenon in Psoriasis and Lichen Planus

Study Overview
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Brief Summary
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Psoriasis and lichen planus often occur at mechanically irritated skin sites (e.g. tight clothing). The investigators would like to investigate this phenomenon in more detail in this study. For this purpose, the skin is specifically irritated at a small and cosmetically favorable site by tearing off scotch tape or rubbing with a wooden spatula. In order to be able to examine the inflammatory processes caused by the irritation more closely, a small skin sample and a skin swab are taken from the irritated area. This skin sample and the swab are repeated after three and fourteen days.

Official Title
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A Prospective Study to Investigate the Pathophysiology of the Koebner's Phenomenon in Psoriasis and Lichen Planus

Conditions
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Kobner Phenomenon, Psoriasis, Lichen Planus

Intervention / Treatment
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* Procedure: Tape stripping


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Dermatologist diagnosed psoriasis (group psoriasis), lichen planus (group lichen planus) or no skin disease (group healthy controls) Subject is capable of giving informed consent Signed informed consent Exclusion Criteria: Use of systemic immunosuppressive/immunmodulating agents in the last three months Use of topical anti-inflammatory treatment in the last 7 days in the area of sampling. Phototherapy in the last 4 weeks Active or recurrent serious bacterial, fungal or viral infection at the time of enrollment by patient history, including patients with Human Immunodeficiency Virus (HIV) infection, Hepatitis B and Hepatitis C infection, active or untreated latent tuberculosis. Female patients of childbearing potential who are pregnant or breast feeding or planning a pregnancy during the duration of the trial and/or not practicing acceptable birth control for the duration of the trial Known or suspected non-compliance, drug or alcohol abuse, Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant, Previous enrolment into the current study, Enrolment of the investigator, his/her family members, employees and other dependent persons.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tape stripping<br> | Procedure: Tape stripping<br>* a small area of skin will be tape-stripped with adhesive tape for up to 40 times and/or rubbed with a wooden spatula until the skin shows a slight erythema<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in the transcriptomic profile comparing psoriasis patients with and without induced koebner phenomenon | Transcriptomic profile at all timepoints (reads per 55µm diameter dot) | Day 0, Day 3 (optional), Day 14 (optional) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in the proteomic profile comparing psoriasis patients with and without induced koebner phenomenon | Olink multiplex proteomics analysis at all timepoints | Day 0, Day 3 (optional), Day 14 (optional) | 
| Characterization of involved immune cells in the skin comparing psoriasis patients with and without induced koebner phenomenon | Imaging mass cytometry (skin biopsies) at all timepoints | Day 0, Day 3 (optional), Day 14 (optional) | 
| Characterization of skin mikrobiome | Skin swabs at all timepoints, analyzed by isolation and sequencing of the microbial DNA | Day 0, Day 3, Day 14 |