Stratum corneum intercellular lipid matrix and corneodesmosomes (SC-ILM/CD)

The stratum corneum intercellular lipid matrix and corneodesmosomes constitute the primary physical and chemical barrier of the human skin, often described by the bricks and mortar model [StatPearls, 2023; PubMed: 22670618]. The corneocytes (bricks) are held together by corneodesmosomes, which are specialized protein complexes including desmoglein 1, desmocollin 1, and corneodesmosin [PubMed: 15144458]. Surrounding these cells is an intercellular matrix composed of a precise ratio of ceramides, cholesterol, and free fatty acids that prevents excessive transepidermal water loss and blocks the entry of pathogens and allergens [Journal of Investigative Dermatology, 2012]. In diseases like atopic dermatitis and ichthyosis, defects in either the lipid composition or the enzymatic degradation of corneodesmosomes lead to barrier dysfunction and chronic inflammation [PubMed: 21645444]. Therapeutic strategies target this complex through the application of barrier-repair lipids to restore the matrix or keratolytic agents like salicylic acid and urea to facilitate desquamation by breaking down corneodesmosomal bonds [PubMed: 10886272]. Understanding the regulation of this matrix is crucial for developing effective topical delivery systems and treating various dermatological conditions [PubMed: 16060709].

Other names

Skin barrierEpidermal permeability barrierCorneocyte-lipid complexIntercellular lipid lamellaeCorneodesmosomal junctional complex

Keratolysis (disruption of corneodesmosomal bonds), barrier restoration (lipid replenishment), occlusion (prevention of water loss), and modulation of corneocyte shedding.