Lipid Rafts and Caveolae in the Terminal Differentiation of Epidermal Keratinocytes

Truus Roelandt1, Diane Roseeuw1, Christina Giddelo1, Jean-Pierre Hachem*, 1, 2
1 Department of Dermatology, Universitair Ziekenhuis Brussel, Brussels, Belgium
2 Centre Hospitalier Emile Mayrisch, Esch Sur Alzette, Luxembourg

© 2009 Roelandt et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Department of Dermatology, Universitair Ziekenhuis Brussel, Laarbeeklaan 101, Brussels 1090, Belgium;


Lipid rafts are cholesterol and sphingolipid-enriched plasma membrane domains, Caveolae represent a subclass of lipid rafts and the chief structural proteins are caveolins (caveolin-1, -2 and –3). Caveolae formation plays a major role in epidermal barrier permeability, regulating lamellar body secretion and terminal differentiation. Disruption of the epidermal barrier leads to protease-activated receptor-2 activation and an increased intracellular calcium resulting in lamellar body secretion. Caveolin-1 is transported via the lamellar bodies to the plasma membrane, inserted into lipid rafts and initiates caveolae formation. The insertion of caveolin-1 serves as a “brake” in lamellar body secretion and signals terminal differentiation in order to restore an efficient epidermal barrier.

Keywords: Caveolae, lipid rafts, lamellar body secretion, terminal differentiation.