The aim of this study was to analyse viability, growth, differentiation and drug metabolic capacity of cultured human keratinocytes obtained from post-mortem skin. Epidermal cells were prepared from 1-day post-mortem paired sun-exposed (outer) and sun-protected (inner) sites of the upper arm, of donors aged 47-80 years. The percentage of viable cells obtained from post-mortem skin was only slightly lower than that usually obtained for keratinocytes isolated from fresh skin, and no alterations of epidermal markers were noted. Keratinocytes isolated post-mortem from non-exposed skin had a higher viability (78 versus 73%), and a more active proliferation, while their attachment rate, keratin composition, lipid synthesis capacity and transglutaminase activity levels were similar to those of epidermal cells obtained from the sun-exposed skin. Keratinocytes isolated from post-mortem skin expressed various phase I and II activities at levels similar to those obtained with keratinocytes isolated from fresh skin while drug metabolizing enzyme activities were consistently higher in sun-exposed compared to sun-protected cells. The results support the conclusion that skin collected post-mortem can represent an alternative source of viable and functional epidermal cells, and that the functional changes that occur in adult keratinocytes habitually exposed to the sun, affect much more strongly the drug metabolism capacity than the expression of differentiation markers.