Atomic force microscopy study on human keratinocytes treated with HgCl2

Morphological modifications of the cellular membrane of human keratinocytes treated with HgCl2 at different concentrations were investigated employing atomic force microscopy and Raman microspectroscopy techniques. Important changes in the surface structure of the keratinocytes membrane occur when this chemical treatment is performed. Mercury action gives rise to roughness and hole-like depressions, especially at cytotoxic concentration. Such surface features are mainly localized in peripheral zones of cells. Although the viability assay reveals that the exposure of keratinocytes to HgCl2 at a concentration of 10-6 M has no cytotoxic effect, morphological modifications are also evident in cellular membrane at such concentration. Raman microspectroscopy measurements suggest that such morphological modifications are related to modifications occurring in the lipidic layer. Our findings show that atomic force microscopy can be a valid and useful tool in studying the changes in morphology of cells when exposed to chemical stress.