HUMAN KERATINOCYTE CELL-CULTURE FOR STUDYING SKIN IRRITATION IN MAN

Four basic compounds, i.e., imipramine, norephedrine, nicotine and 8-aminoquinoline, were evaluated for their toxic effects on cultured epidermal keratinocytes and the results compared to in vivo irritancy testing. Morphological changes and cell proliferation inhibition on confluent cultures were examined at concentrations ranging from 0.1 to 10% (w/v). Exposure to four bases resulted in dose-dependent changes in cell morphology and cell growth inhibition. The rank order of decreasing damage was as follows: imipramine > 8-aminoquinoline > norephedrine > nicotine. The relevance of in vitro toxicity data was assessed in terms of human skin irritation response obtained after applying four bases on the back of 16 healthy women volunteers for 24 h. Except for 8-aminoquinoline, in vitro results appeared to correlate with in vivo skin irritation data.