AFM IMAGING AND ELASTICITY MEASUREMENTS ON LIVING RAT-LIVER MACROPHAGES

The authors investigated the morphology and the elastic properties of living cultured rat liver macrophages (Kupffer cells) with an atomic f orce microscope (AFM). Continuous imaging and elasticity mapping of in dividual cells in physiological buffer was carried out for several hou rs without damaging the cells as judged by their persistent undisturbe d morphology. Dynamic events such as protrusive activity were observed in time course. The importance of the cytoskeleton for the mechanical properties of the cell has been investigated by measuring the cell's elasticity as a function of position. Chemical disassembly of the acti n network by applying 10 mu g/ml cytochalasin B decreased the cell's a verage elastic modulus seven-fold within less than 40 minutes. Treatin g the cells with 0.1 mu g/ml latrunculin A resulted in a two-fold decr ease in the elastic modulus merely in the perinuclear region after 40 minutes, whereas other parts of the cell were not affected. (C) 1997 A cademic Press.