Abstract
The recent increase in understanding of cell death has promoted new approaches in toxicological studies, mainly those dealing within vitro systems where the evaluation of cell death has been the most widely adopted end-point in measuring the effects of chemical toxicants. The aim of this study was to investigate the possibility of improving the traditional cytotoxicity test protocols in order to produce more specific information on the type of cell death induced by exposure to toxicants. In particular, we characterized the mode of cell death in an established epithelial cell line, HEp-2 cells, which is frequently used in cytotoxicity testing owing to its easy handling and standardization of culture conditions. Reference chemicals for apoptosis and necrosis were selected as controls, together with other molecules that have been shown, in preliminary studies, to induce various morphological and structural modifications in relation to cell death. The results obtained show that: (a) the floating fraction of treated cells gives the clearest picture of the necrotic/apoptotic distribution; (b) morphological analysis is crucial for characterization of apoptosis; (c) more than one cytotoxic end-point is necessary to clearly identify the type of cell death.
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Turco, L., De Angelis, I., Stammati, A. et al. Apoptosis evaluation in epithelial cells exposed to different chemicals: relevance of floating cells. Cell Biol Toxicol 16, 53–62 (2000). https://doi.org/10.1023/A:1007696604725
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DOI: https://doi.org/10.1023/A:1007696604725