Brownian motion of nucleated cell envelopes impedes adhesion.
We demonstrate that composite envelopes of nucleated cells exhibit pronounced short wavelength (<or=0.5 microm) bending excitations of approximately 10 nm root mean square amplitudes at physiological temperatures, which impede strong adhesion due to entropic repulsion forces. Quantitative microinterferometric analysis of the dynamic cell surface roughness of macrophages in terms of the theory of statistical surfaces suggests that the membrane excitations are mainly thermally driven Brownian motions (although active driving forces may contribute substantially). We determine the effective bending modulus of the cell envelope (approximately 1000kBT), the cortical tension (approximately 10(-4) N m-1), and the work of adhesion (approximately 10(-5) J m-2).
Physics Department E22, Technical University Munich, D-85748 Garching, Germany. zidovska@mrl.ucsb.edu
Alexandra
A
Zidovska
Erich
E
Sackmann
D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology*; D002463:Cell Membrane Permeability / Q000187:drug effects; D002478:Cells, Cultured; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D008954:Models, Biological; D009038:Motion; D009219:Myosin-Light-Chain Kinase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology
D047428:Protein Kinase Inhibitors; D013844:Thiazoles; D009219:Myosin-Light-Chain Kinase; D004121:Dimethyl Sulfoxide