1. Origin of the Corneocyte Lipid Envelope (CLE): Observations in Harlequin Ichthyosis and Cultured Human Keratinocytes 
Peter M. Elias, Manigé Fartasch, Debra Crumrine, Martin Behne, Yoshikazu Uchida, Walter M. Holleran 
Journal of Investigative Dermatology 
Volume 115, Issue 4, Pages (October 2000)
DOI: /j x
Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

2. Figure 1
The CLE appears as a bilayer structure in pyridine-treated murine stratum corneum. (A–C) Murine SC treated for 2 (A) and 16 (B, C) h with pyridine. The CLE is more visible in samples treated for the longer period (B, C: arrowheads), and at sites of desmosomes (d) embedded in the CE. (D) Murine stratum corneum treated for 16 h with chloroform:methanol (Wertz et al. 1989a). The CLE is only seen occasionally, and when visible, unilamellar images predominate (single arrowhead), although occasional dense-lucent-dense images can be found (double arrowheads). Scale bar: 0.2 μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

3. Figure 2
A CLE is present around corneocytes in harlequin ichthyosis. Few or no LB were present in these subjects. No extracellular membranes are seen; vesicular structures (A–C, asterisks) persist in the corneocyte cytosol, and a prominent CLE is present around corneocytes in all HI subjects (A–C, arrows). Following pyridine treatment of aldehyde/osmium tetroxide fixed samples, the dense-lucent-dense structure of the CLE can be seen (D, arrows). (A–C) Ruthenium tetroxide postfixation. Scale bar: 0.2 μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

4. Figure 3
A CLE is present around corneocytes in postconfluent human keratinocyte cultures. (A, B) Non-pyridine-treated cultures reveal a continuous electron-lucent gap and an electron-dense external leaflet around corneocytes (A, CLE gap, solid arrows;B, CLE external leaflet, open arrows). (C) Pyridine treatment of parallel cultures reveals the CLE to comprise a dense-lucent-dense structure (solid arrows). (A–C) Osmium tetroxide postfixation. Scale bar: 0.2 μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

5. Figure 4
Membrane events during epidermal terminal differentiation. Schematic model of changes in membrane lipid composition/localization that occur during CLE formation, including: (1) fusion of the limiting membrane of the lamellar body with the plasma membrane of the apical stratum granulosum cell (lower panel); (2) covalent attachment of Cer and fatty acids to CE proteins (red) (upper panel); and (3) removal of glucose moieties (Glc) from GlcCer, resulting in the dense-lucent-dense structure of the CLE. Shaded areas (gray) indicate areas of high electron density; i.e., electron-rich headgroup domains (blue), with acyl domains (green) of low electron density.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions