title: Role of the epidermal barrier in atopic dermatitis.
abstract: The skin's permeability barrier protects against extensive water loss and prevents the entry into the skin of harmful substances like irritants, allergens and microorganisms. The permeability barrier is mainly located in the stratum corneum and consists of corneocytes and a lipid-enriched intercellular domain. The barrier is formed during epidermal differentiation. In atopic dermatitis the skin barrier is disturbed already in non-lesional skin. The disturbed skin barrier allows the entry of environmental allergens from house dust mites, animal dander and grass pollen into the skin. In predisposed individuals these allergens may trigger via immunologic pathways the inflammation of atopy. The causes for the disturbed epidermal skin barrier are changes in skin lipids and in epidermal differentiation, in particular filaggrin mutations. Filaggrin mutations lead to a disturbed skin barrier and dry skin which are hallmarks in atopic dermatitis. Therapeutic agents influence the skin barrier differently; topical therapy with potent corticosteroids does not lead to the repair of the barrier in atopic dermatitis, whereas therapy with the calcineurin inhibitors and lipid-containing emulsions support barrier repair.
authors.affiliation: Department of Dermatology, Venerology, and Allergology, University Clinic of Schleswig-Holstein, Campus Kiel, University of Kiel, Germany.
authors.forename: Ehrhardt
authors.initials: E
authors.lastname: Proksch
authors.forename: Regina
authors.initials: R
authors.lastname: Fölster-Holst
authors.forename: Matthias
authors.initials: M
authors.lastname: Bräutigam
authors.forename: Marjan
authors.initials: M
authors.lastname: Sepehrmanesh
authors.forename: Stephan
authors.initials: S
authors.lastname: Pfeiffer
authors.forename: Jens-Michael
authors.initials: JM
authors.lastname: Jensen
mesh_terms: D003198:Computer Simulation; D003876:Dermatitis, Atopic / Q000503:physiopathology*; D004817:Epidermis / Q000503:physiopathology*; D000091344:Filaggrin Proteins; D006801:Humans; D050356:Lipid Metabolism; D008954:Models, Biological