Growth factor assays for normal human hepatocytes and hepatoma cells

Summary An improved assay procedure of growth factors for normal human hepatocytes and hepatoma cells is reviewed. The combined use of improved cell isolation and dispersion procedures and a selective culture medium supports the response of human parenchymal cells homogenous to growth factors under serum-free culture conditions. Differentiated human hepatoma cells (HepG2), which synthesize and secrete the liver-specific plasma proteins and enzymes, provide a useful model for comparative study of growth factor requirements of hepatoma cells to normal hepatocytes. HepG2 cells grow in protein-free, defined medium at high cell density. This indicates that the hepatoma cells may secrete autocrine growth factors into the medium. HepG2 cells at low cell density permit detection of exogeneous growth factors that may be secreted by HepG2 cells at high cell density. HepG2 cells at high cell density are a useful assay for growth inhibitory activities for hepatoma cells.