The architecture of mammalian skin incorporates an outer layer of stratified epithelium. This enables the organism to conserve internal homeostasis and maintain protection from adverse environmental exposure. The keratinocyte is the cell primarily responsible for this structure. Isolation and in vitro cultivation of this cell type is widely used in dermatological and other investigations as opposed to using whole animals. However, this cell is very fastidious as compared to other skin cells (fibroblasts, etc.) and thus requires special procedures to obtain successful in vitro cultivation. This chapter describes the methodology required to isolate, purify, and cultivate keratinocytes to produce both monolayer and stratified cultures. The methodologies for producing cultures of keratinocytes obtained from rat skin and from human skin are described.
