Skin Barrier Function and Allergens

TY - JOUR

T1 - Skin Barrier Function and Allergens

AU - Engebretsen, Kristiane Aasen

AU - Thyssen, Jacob Pontoppidan

N1 - © 2016 S. Karger AG, Basel.

PY - 2016

Y1 - 2016

N2 - The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization (CS) and allergy following increased penetration of potential allergens. However, the relationship between common dermatoses such as psoriasis, atopic dermatitis (AD) and irritant contact dermatitis (ICD) and the development of contact allergy (CA) is complex, and depends on immunologic responses and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due to increased levels of Th17 cells and its associated cytokines. As for AD, a positive association to CS has been established in epidemiological studies, but is still unresolved. Experimental studies show, however, an inverse relationship between AD and CS. The opposing and antagonistic influences of Th1 (CS) and Th2 (AD) have been proposed as an explanation. Finally, there is convincing evidence that exposure to irritants increases the risk of CS, and patients with ICD are, therefore, at great risk of developing CA. Skin irritation leads to the release of IL-1 and TNF-α, which affects the function of antigen-presenting cells and promotes their migration to local lymph nodes, thus increasing the probability of CS and ultimately the development of CA.

AB - The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization (CS) and allergy following increased penetration of potential allergens. However, the relationship between common dermatoses such as psoriasis, atopic dermatitis (AD) and irritant contact dermatitis (ICD) and the development of contact allergy (CA) is complex, and depends on immunologic responses and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due to increased levels of Th17 cells and its associated cytokines. As for AD, a positive association to CS has been established in epidemiological studies, but is still unresolved. Experimental studies show, however, an inverse relationship between AD and CS. The opposing and antagonistic influences of Th1 (CS) and Th2 (AD) have been proposed as an explanation. Finally, there is convincing evidence that exposure to irritants increases the risk of CS, and patients with ICD are, therefore, at great risk of developing CA. Skin irritation leads to the release of IL-1 and TNF-α, which affects the function of antigen-presenting cells and promotes their migration to local lymph nodes, thus increasing the probability of CS and ultimately the development of CA.

KW - Allergens

KW - Animals

KW - Dermatitis, Allergic Contact

KW - Dermatitis, Atopic

KW - Dermatitis, Irritant

KW - Epidermis

KW - Humans

KW - Psoriasis

KW - Skin Physiological Phenomena

KW - T-Lymphocytes, Helper-Inducer

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

KW - Review

U2 - 10.1159/000441548

DO - 10.1159/000441548

M3 - Journal article

C2 - 26844901

SN - 1421-5721

VL - 49

SP - 90

EP - 102

JO - Current Problems in Dermatology

JF - Current Problems in Dermatology

ER -