Human cultured lens cells. II. Characterization of established lens cell lines and test of their suitability for cytotoxicity tests

Abstract

Human lens cells in culture may be valuable tools to discover cataractogenic risk factors. Here we report on the characterization of established human lens cells and their use in cytotoxicity tests. Adhesion dependence was tested by an autoradiographic method. Soft agar test was performed to secure anchorage-independent growth. Laser scan microscopy was used for measuring the nucleus-cytoplasmic relationship. The cytoskeleton was visualized by fluorescence microscopy. Investigations on cytotoxicity were done by neutral red cytotoxicity assay and 3H-thymidine incorporation. The labeling index was determined by the BrdU-method. Two lens cell lines were transformed into fast growing cells. They are characterized by a partial loss of adhesion dependence, cell growth in soft agar, high cloning efficiency and reduced serum requirement. However, the nucleus-cytoplasmic relationship did not change very much in comparison to non-transformed lens cells. The organization of the cytoskeleton was cell shape dependent. The intermediate filaments were from the vimentin type. The established cell lines proved to be highly sensitive to ethanol and mitomycin C. The established human lens cell lines are well suited to screen for cytotoxic substances in vitro which might be cataractogenic risk factors in vivo.