Stratum corneum lipid lamellae and corneocyte lipid matrix (SC lipid matrix) (SC lipid matrix)

The stratum corneum (SC) lipid lamellae and corneocyte lipid matrix constitute the primary permeability barrier of the skin, often described by the 'bricks and mortar' model where corneocytes are the bricks and the lipid matrix is the mortar. This matrix is composed of a unique mixture of ceramides, cholesterol, and free fatty acids in an approximately 1:1:1 molar ratio, organized into highly ordered lamellar bilayers. Its primary biological function is to prevent excessive transepidermal water loss (TEWL) and protect the body from environmental insults, including pathogens and allergens. In diseases like atopic dermatitis and psoriasis, the lipid composition and organization are significantly altered, leading to barrier dysfunction and increased sensitivity. Therapeutic strategies target this matrix through the application of barrier-repair lipids, such as ceramides, or occlusive agents like petrolatum to restore integrity and improve skin hydration. Additionally, penetration enhancers may be used to temporarily disrupt this matrix to facilitate the transdermal delivery of other therapeutic agents.

Other names

Skin barrier lipidsIntercellular lipid matrixStratum corneum extracellular matrixCornified lipid envelope (CLE)SC lipid bilayersEpidermal lipid barrier

Barrier restoration through replenishment of physiological lipids, occlusion to reduce transepidermal water loss, and modulation of lipid fluidity to enhance drug penetration.