Three-Dimensional Analysis of Cell Division Orientation in Epidermal Basal Layer Using Intravital Two-Photon Microscopy

PLoS One. 2016 Sep 22;11(9):e0163199. doi: 10.1371/journal.pone.0163199. eCollection 2016.

Abstract

Epidermal structures are different among body sites, and proliferative keratinocytes in the epidermis play an important role in the maintenance of the epidermal structures. In recent years, intravital skin imaging has been used in mammalian skin research for the investigation of cell behaviors, but most of these experiments were performed with rodent ears. Here, we established a non-invasive intravital imaging approach for dorsal, ear, hind paw, or tail skin using R26H2BEGFP hairless mice. Using four-dimensional (x, y, z, and time) imaging, we successfully visualized mitotic cell division in epidermal basal cells. A comparison of cell division orientation relative to the basement membrane in each body site revealed that most divisions in dorsal and ear epidermis occurred in parallel, whereas the cell divisions in hind paw and tail epidermis occurred both in parallel and oblique orientations. Based on the quantitative analysis of the four-dimensional images, we showed that the epidermal thickness correlated with the basal cell density and the rate of the oblique divisions.

Grants and funding

This research was supported by MEXT/JSPS KAKENHI Grant Number JP15H05953 “Resonance Bio” and JP26242082 (TN), JP25-1699 (SI) and JP25560411 (TH) and by the NIBB Priority Collaborative Research Project (#15-406). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.