Nanostructure of the Epidermal Extracellular Space as Observed by Cryo-Electron Microscopy of Vitreous Sections of Human Skin

• Published in: Journal of investigative dermatology Vol. 124; no. 4; pp. 764 - 777
• Main Authors: Al-Amoudi, Ashraf, Dubochet, Jacques, Norlén, Lars
• Format: Journal Article
• Language: English
• Published: Danvers, MA Elsevier Inc 01.04.2005; Nature Publishing; Elsevier Limited
• Subjects: Adult; Biological and medical sciences; cadherin; Cell Differentiation; Cell Membrane - ultrastructure; CEMOVIS; ceramides; corneocytes; corneodesmosomes; cryo-electron microscopy; cryo-fixation; cryo-TEM; Cryoelectron Microscopy; cubic membranes; cubic phases; Dermatology; desmosomes; Desmosomes - ultrastructure; epidermis; Epidermis - ultrastructure; Extracellular Space; Humans; Lipid Bilayers; Male; Medical sciences; Medicin och hälsovetenskap; skin barrier; skin lipids; stratum corneum; skin barrier; cubic membranes; cubic phases; cadherin; ceramides; corneodesmosomes; cryo-fixation; stratum corneum; cryo-TEM; corneocytes; skin lipids; desmosomes; CEMOVIS; cryo-electron microscopy; epidermis; Human; Stratum corneum; Dermatology; Epidermis; Lipids; Barrier; Nanostructure; Desmosome; Cadherin; Electron microscopy; Extracellular space; Anatomic pathology; Transmission electron microscopy; Ultrastructure; Ceramide; Skin; cadherin/CEMOVIS/ceramides/corneocytes/corneodesmosomes/cryo-electron microscopy/cryo- fixation/cryo-TEM/desmosomes/epidermis/skin barrier/skin lipids/stratum corneum/cubic membranes/cubic phases
• ISSN: 0022-202X; 1523-1747
• DOI: 10.1111/j.0022-202X.2005.23630.x

The newly developed method, cryo-electron microscopy of vitreous sections, was used to observe the nanostructure of the epidermal extracellular space. The data were obtained from vitreous sections of freshly taken, fully hydrated, non-cryo-protected human skin. The extracellular space of viable epidermis contains desmosomes, expressing a characteristic extracellular transverse ∼5 nm periodicity, interconnected by a relatively electron lucent inter-desmosomal space. The extracellular space between viable and cornified epidermis contains transition desmosomes at different stages of reorganization interconnected by widened areas expressing a rich variety of complex membrane-like structures. The extracellular space of cornified epidermis contains ∼9, ∼14, ∼25, ∼33, ∼39, ∼44, and ∼48 nm thick regions in turn containing one, two, four, six, eight, eight, and ten parallel electron-dense lines, respectively, between adjacent corneocyte lipid envelopes. The eight-line ∼44 nm thick regions are most prevalent.