Mechanism of murine epidermal maintenance: Cell division and the Voter Model

TL;DR

This study uses a voter-model framework to explain cell proliferation and spatial regulation in mouse epidermis, demonstrating that proliferating cells tend to cluster, which aligns with experimental observations.

Contribution

It introduces a voter-model based approach to understand spatial regulation and clustering in epidermal cell proliferation, linking theory with biological data.

Findings

Proliferating cells form clusters in the basal layer.

Simple stochastic rules accurately predict cell population dynamics.

Empirical data confirms clustering predicted by the model.

Abstract

This paper presents an interesting experimental example of voter-model statistics in biology. In recent work on mouse tail-skin, where proliferating cells are confined to a two-dimensional layer, we showed that cells proliferate and differentiate according to a simple stochastic model of cell division involving just one type of proliferating cell that may divide both symmetrically and asymmetrically. Curiously, these simple rules provide excellent predictions of the cell population dynamics without having to address their spatial distribution. Yet, if the spatial behaviour of cells is addressed by allowing cells to diffuse at random, one deduces that density fluctuations destroy tissue confluence, implying some hidden degree of spatial regulation in the physical system. To infer the mechanism of spatial regulation, we consider a two-dimensional model of cell fate that preserves the overall population dynamics. By identifying the resulting behaviour with a three-species variation of the "Voter" model, we predict that proliferating cells in the basal layer should cluster. Analysis of empirical correlations of cells stained for proliferation activity confirms that the expected clustering behaviour is indeed seen in nature.