Human epidermal keratinocytes in culture: a story of multiple recipes for a single cell type

Background: For one half-century, cultures of human epidermal keratinocytes have opened new paths of research in skin biology and dermatology. Either performed with serum and feeder-layer, in serum-free conditions, or in autocrine conditions, cells cultured as monolayers became research materials for basic science and dermatology, as well as a source for grafting, particularly to treat severely burned patients. More recently tissue reconstruction at air-liquid interface has opened new perspectives for in vitro toxicology, studies of epidermal barrier, and modeling skin diseases. Summary: This review presents a brief retrospective of the emergence of keratinocyte-based culture techniques. It also presents opportunities and eventual problems that researchers might encounter when exploring the skin using such procedures. Key Messages: While methodologies in tissue culture evolve, the multiplicity of procedures concomitantly increases, requiring to make some selective but difficult choice. Keeping tracks of technological evolution in epidermal cell culture should help choosing the adequate methodology for a specific investigation or innovating with new, more dedicated ones.