Polymorphic Light Eruption | Regulatory T Cells (Tregs) in Polymorphic Light Eruption

Polymorphic Light Eruption research study

What is the primary objective of this study?

Polymorphic light eruption (PLE) is a photodermatosis with an extremely high prevalence, particularly among young women (up to 20%). The disease is characterized through itchy skin lesions on sun-exposed body sites occurring after sun exposure mostly in spring and early summer. Its etiopathogenesis is unknown but resistance to UV-induced immunosuppression with subsequent immune reactions against skin photoneoantigens has been suggested. Regulatory T cells (CD4+CD25+FoxP3+) (Tregs), a subset of T helper cells, are crucial for the induction of immunosuppression. We will test the hypothesis that PLE patients show pathogenic fluctuating Treg levels and function and related parameters over the seasons of the year, possibly being responsible for lack of immune modulation and autoimmunity in PLE. Natural or medical photohardening may normalize Treg deficiency in PLE and lead to clinical adaption in summer. Better insight into the pathogenesis of PLE may give clues to develop new therapeutic strategies.

Who is eligible to participate?

Inclusion Criteria: - Age above 18 years - Patients with confirmed PLE diagnosis either by typical anamnesis and/or typical histology of lesions and/or positive phototesting results (group 1 and 2); healthy subjects (group 3); patients with phototherapy-responsive disease (including psoriasis, atopic dermatitis, and other conditions (group 4). - Good general health status Exclusion Criteria: - Presence or history of malignant skin tumors - Dysplastic melanocytic nevus syndrome - Certain photosensitive disorders (including porphyria, chronic actinic dermatitis, Xeroderma pigmentosum, basal cell nevus syndrome) - Autoimmune disease (lupus erythematodes, scleroderma, dermatomyositis) - Systemic treatment with steroids and/or other immunosuppressive drugs within the last 6 months - Antinuclear antibodies (ds-DNA, Ro, La) - First-degree relatives of PLE patients (exclusion criterion for group 3 and 4 - Pregnancy and breastfeeding - Ongoing or planned specific hyposensitization treatment (i.e. specific immunotherapy)

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?

Polymorphic Light Eruption


Atopic Eczema

Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

1Patients with polymorphic light eruption without medical photohardening treatment

2Patients with polymorphic light eruption treated with medical photohardening

3Patients with other disorders (including psoriasis) treated with phototherapy

4Normal healthy subjects

Study Status


Start Date: March 2008

Completed Date: December 2014


Type: Observational


Primary Outcome: Treg level and function

Secondary Outcome: Blood and/or skin cytokine and chemokine levels, vitamin D status, and other immunoregulatory parameters (see above)

Study sponsors, principal investigator, and references

Principal Investigator: Peter Wolf, MD

Lead Sponsor: Medical University of Graz


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