Interactions of asbestos fibers with hepatocytes in vitro: an ultrastructural study

Cultures of rat hepatocytes have been used to study the interaction of chrysotile asbestos fibers with epithelial cells. The hepatocytes were incubated for 20 h with chrysotile asbestos (UICC B and a preparation of short fibers: 90% less than 2 micron) at concentrations of 1 or 10 micrograms/ml. Morphologic studies were then performed by means of transmission electron microscopy. Fibers were incorporated into plasma membrane invaginations, cytoplasmic vacuoles and phagolysosomes. These observations demonstrate that rat hepatocytes can engage in phagocytosis of chrysotile fibers. The results are compared to those previously obtained with mesothelial cells and tracheobronchial epithelium, exposed to asbestos in vitro. The advantages of the hepatocyte model to investigate the effects on cells of the association of asbestos fibers with genotoxic agents in relation to carcinogenesis are discussed.