Skin barrier integrity

The **skin barrier** refers to the composite structure and function provided primarily by the outermost layers of the epidermis—especially the stratum corneum—and associated elements such as intercellular lipids (ceramides, cholesterol), tight junctions in granular layers, cornified envelopes formed from keratinocytes/filaggrin aggregation, desmosomes/corneodesmosomes for cell adhesion, and an acidic pH environment. This multi-layered system protects against environmental insults (physical trauma, pathogens), prevents excessive water loss from within ("IN–OUT" function), maintains optimal hydration/pH for enzymatic activity and microbiome balance ("OUT–IN" protection), and modulates local immune responses. Disruption in any component can lead to increased susceptibility to inflammatory diseases like eczema/atopic dermatitis or ichthyosis vulgaris due to impaired structural proteins such as filaggrin or altered lipid composition. The term "skin barrier/mucosal membrane integrity" is not a canonical molecular target but describes an emergent property resulting from coordinated action among many molecules; thus it is not considered a druggable therapeutic target in itself but rather an endpoint influenced by targeting its constituent proteins/lipids/pathways.[1][2][4][5] Note: This entry is marked **incorrect** because "Skin barrier/mucosal membrane integrity" does not refer to a single molecule/receptor/protein but instead describes an overall tissue-level property dependent on multiple interacting components. For structured data purposes it should be replaced with specific targets such as "Filaggrin," "Ceramide synthase," etc.[2][6]

Other names

Epidermal barrierStratum corneum barrierCutaneous barrierMucosal membrane integrity (when referring to mucosa)