Cultured human epidermal cells as a tool in skin toxicology

Cultured human epidermal cells have been used to study the effects of toxic compounds on cell growth and on the integrity of the cellular membrane. To determine the concentration causing a 50% inhibition of growth rate, keratinocyte cultures were exposed to the test compound in concentrations of 10 −9–10 −6 m for 48 hr during the exponential growth phase and growth was calculated from the DNA content. To measure cell damage, fully grown cultures were exposed to a 10 −4 m concentration and the activities of two intracellular enzymes and the K + concentration of the cells were determined at intervals over 4–24 hr. Data obtained so far indicate that this technique may be useful in testing for dermatotoxicity and in studying mechanisms of toxic action.