Physical interpretation of the maximum receptor-ligand bond spacing to ensure cell adhesion in ligand-coated substrates

Langmuir. 2008 Jun 3;24(11):5644-6. doi: 10.1021/la800048e. Epub 2008 May 6.

Abstract

Recent experiments by Arnold et al. (Arnold, M.; Cavalcanti-Adam, E. A.; Glass, R.; Blummel, J.; Eck, W.; Kantlehner, M.; Kessler, H.; Spatz, J. P. ChemPhysChem 2004, 5, 383) revealed that a distance of less than 58-73 nm between receptor-ligand bonds is necessary to ensure focal adhesion in integrin-mediated cell adhesion on ligand-coated substrates. In this letter, we consider focal adhesion growth to be a process assisted by thermal fluctuations and receptor-ligand binding and resisted by repulsive "bulge pressure" and membrane deformation. By applying balance between these forces, we obtain a critical spacing of receptor-ligand bonds given as 2h[alpha kBT/beta Eh3)1/3(E/p)5]1/14, above which the growth of focal adhesion becomes difficult. Here h and E are the in-plane modulus and thickness of a cell membrane, respectively, p is a repulsive "bulge pressure" between the cell membrane and substrate, and alpha and beta are constants on the order of 1. We use typical values of E and h for cell membranes and obtain the critical spacing of receptor-ligand bonds of around 39-89 nm for a wide range of repulsive bulge pressure.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cell Adhesion / physiology
  • Cell Membrane / metabolism*
  • Focal Adhesions / physiology*
  • Humans
  • Integrins / metabolism*
  • Ligands*
  • Models, Biological*
  • Pressure

Substances

  • Integrins
  • Ligands