Geometrical and topological analysis ofin vivoconfocal microscopy images reveals dynamic maturation of epidermal structures during the first years of life

Abstract

Abstract. Reflectance confocal microscopy is successfully used in infant skin research. Infant skin structure, function, and composition are undergoing a maturation process. We aimed to uncover how the epidermal architecture and cellular topology change with time. Images were collected from three age groups of healthy infants between one and four years of age and adults. Cell centers were manually identified on the images at the stratum granulosum (SG) and stratum spinosum (SS) levels. Voronoi diagrams were used to calculate geometrical and topological parameters. Infant cell density is higher than that of adults and decreases with age. Projected cell area, cell perimeter, and average distance to the nearest neighbors increase with age but do so distinctly between the two layers. Structural entropy is different between the two strata, but remains constant with time. For all ages and layers, the distribution of the number of nearest neighbors is typical of a cooperator network architecture. The topological analysis provides evidence of the maturation process in infant skin. The differences between infant and adult are more pronounced in the SG than SS, while cell cooperation is evident in all cases of healthy skin examined.

A 3D self-organizing multicellular epidermis model of barrier formation and hydration with realistic cell morphology based on EPISIM

“…1A). Further, topological analysis of experimental data acquired by in vivo confocal reflectance microscopy25 matches well to the neighbour topology that emerges from the interactions of biomechanics with cell turnover and differentiation in our model (Fig. 1B).…”

“…As previously described, we used Voronoi diagrams and Delaunay triangulation to evaluate the spatial organization of cells in relation to their neighbours in epidermal optical sections obtained by in vivo confocal reflectance microscopy25. Briefly, we calculate the Voronoi diagram and its dual Delaunay triangulation graph on a pre-selected Region of Interest (ROI) in each image (Fig.…”

“…1B). This network of polygons represents the spatial organization of the cells in the selected ROI, which we use to calculate the number of Delaunay neighbours per cell25.…”

Sonnenschutz bei Säuglingen

“…Nach der Geburt setzen sich die in utero begonnenen Rei fungsprozesse der Hautbarriere und deren Funktionen fort und dauern über das 1. Lebensjahr hin an [1] [2] [3]. In den ersten Lebensjahren kann die Haut von Säuglin gen und Kleinkindern im Vergleich zu Erwachsenen noch nicht so viel Melanin bilden, welches für die Hautpigmen tierung verantwortlich ist [4][5] [6].…”

Neonatal skin barrier

“…In fact, even the structure at the cellular and tissue levels is changing after birth, with the cell size and thickness of layers progressively increasing . Research is still emerging about different aspects of infant skin maturation including the dynamics of the skin microbiome, topology at the cellular level, and resistance to water transport in the stratum corneum (SC) …”