RESUMO
BACKGROUND/PURPOSE: The knowledge how surfactants and hydrolyzed proteins influence the elastic properties of living epidermal keratinocytes is sparse. We demonstrate that the stiffness of cells measured by atomic force microscope (AFM) can be correlated with viability test. METHODS AND MATERIALS: The effects of sodium lauryl sulphate (SLS) and hydrolyzed collagen (HK) of molecular weight 9 kDa were examined with respect to human keratinocytes viability and elasticity. MTT assay was applied to determine the survival fraction of keratinocytes treated with SLS and HK solutions of various molar ratios. The AFM measurements of the keratinocytes stiffness were carried out immediately after the exposure of cells to the SLS and HK, respectively. RESULTS: The increase of the SLS concentration resulted in the decrease of cells proliferation and this effect was inhibited by addition of HK. The strongest inhibition was observed for the SLS:HK molar ratio equals to 2:1. AFM study shows decrease in the cell stiffness for cells treated with SLS. Fluorescence microscopy reveals remodeling of actin filaments of SLS-treated cells. SLS:HK mixture treatment results in mechanical stiffness close to untreated cells. CONCLUSION: These results provide possible correlations between mechanical properties and viability of keratinocytes when the chemical stress occurs.
