A cellular automaton model of ultraviolet-driven melanin production and distribution in the human epidermis

Abstract

A cellular automaton (CA) model has been developed to simulate the spatio-temporal dynamics of ultraviolet radiation (UVR)-driven melanin production and distribution, commonly known as the tanning response, in human epidermal skin. The model builds upon an existing mathematical framework for the tanning response, incorporating experimental data on the melanin content between epidermal layers of different types of skin before and after exposure to a minimal UVR dose for erythema in an existing experimental study. Calibrated parameter values, aligned closely with the reference model, successfully replicate existing experimental biopsy data for six individuals chosen in the experimental study within ±1% error and show qualitative agreement with the temporal evolution of dendrite length and melanin distribution in the reference model. Due to certain assumptions, simplifications, and approximations that were made to capture the basics of the tanning response, this research provides a foundational framework for future extensions of computational models aimed at quantifying UVR-induced DNA damage in skin using cellular automata.