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Characterisation of Topographical, Biomechanical and Maturation Properties of Corneocytes with Respect to Anatomical Location via Wiley

9 November 2023

Ana S. Évora, Zhibing Zhang, Simon A. Johnson, Michael J. Adams

First published: 22 October 2023


The Stratum Corneum (SC) is the first barrier of the skin. The properties of individual cells are crucial in understanding how the SC at different anatomical regions maintains a healthy mechanical barrier. The aim of the current study is to present a comprehensive description of the maturation and mechanical properties of superficial corneocytes at different anatomical sites in the nominal dry state.

Materials and methods

Corneocytes were collected from five anatomical sites: forearm, cheek, neck, sacrum and medial heel of 10 healthy young participants. The surface topography was analysed using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). The level of positive-involucrin cornified envelopes (CEs) and desmoglein-1 (Dsg1) were used as indirect measures of immature CEs and corneodesmosomes, respectively. In addition, AFM nanoindentation and stress-relaxation experiments were performed to characterise the mechanical properties.


Volar forearm, neck and sacrum corneocytes presented similar topographies (ridges and valleys) and levels of Dsg1 (13–37%). In contrast, cheek cells exhibited circular nano-objects, while medial heel cells were characterized by villi-like structures. Additionally, medial heel samples also showed the greatest level of immature CEs (32–56%, p < 0.001) and Dsg1 (59–78%, p < 0.001). A large degree of inter-subject variability was found for the Young’s moduli of the cells (0.19–2.03 GPa), which was correlated with the level of immature CEs at the cheek, neck and sacrum (p < 0.05).


It is concluded that a comprehensive study of the mechanical and maturation properties of corneocytes may be used to understand the barrier functions of the SC at different anatomical sites.

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