Skin surface lipid barrier (SSLB)

The skin surface lipid barrier is a specialized extracellular matrix located in the stratum corneum, the outermost layer of the epidermis. It is primarily composed of a precise ratio of ceramides, free fatty acids, and cholesterol, which form organized lamellar structures that prevent excessive transepidermal water loss (TEWL) and block the entry of allergens and pathogens (StatPearls, 2023). This barrier is essential for maintaining skin homeostasis and protecting the body from environmental insults such as UV radiation and chemical irritants (International Journal of Molecular Sciences, 2020). In many dermatological diseases, such as atopic dermatitis and psoriasis, the lipid composition is altered, leading to barrier dysfunction, inflammation, and increased sensitivity (Journal of Clinical and Aesthetic Dermatology, 2016). Therapeutic strategies targeting this barrier involve the topical application of physiological lipids to repair the matrix or occlusive agents to provide a temporary physical shield, thereby facilitating the natural healing process of the epidermis (PubMed, 2018). By restoring the integrity of the lipid barrier, these treatments help reduce symptoms like pruritus and dryness while preventing disease flares (NIH, 2022).

Other names

Stratum corneum lipid barrierEpidermal permeability barrierSkin barrierSkin surface lipids

Restoration of the lipid lamellae, occlusion to prevent water loss, and humectancy to attract water into the stratum corneum.